home Heating calculation Veterinary and sanitary examination of carcasses and organs of animals exposed to radiation. Veterinary and sanitary examination and sanitary assessment of carcasses and organs for diseases of livestock and poultry

Veterinary and sanitary examination of carcasses and organs of animals exposed to radiation. Veterinary and sanitary examination and sanitary assessment of carcasses and organs for diseases of livestock and poultry

Lesnoye and Agriculture

Reindeer and camels are also susceptible to foot-and-mouth disease, and among wild animals, elk, deer, antelope, wild boar, roe deer, saiga, bison, bison. A person becomes infected with foot and mouth disease by consuming untreated milk from sick animals, as well as by milking sick animals or processing them for meat. In young animals with foot and mouth disease, catarrh of the upper respiratory tract and acute catarrh of the gastrointestinal tract are found. U individual species In animals, these changes manifest themselves as follows.

44. VSE AND SANITARY ASSESSMENT OF CARCASSES AND ORGANS IN FOOTH AND MOUTH MOUTH. A contagious disease of cattle, sheep, goats and pigs. Reindeer and camels are also susceptible to foot-and-mouth disease, and among wild animals - elk, deer, antelope, wild boar, roe deer, saiga, bison, and bison. Young animals are more sensitive to foot and mouth disease than older ones; they become seriously ill and often die. A person becomes infected with foot and mouth disease by consuming untreated milk from sick animals, as well as by milking sick animals or processing them for meat. CAUSE: virus. Consists of RNA and a protein shell, polyvariable. There are types A, O, C, SAT-1, SAT-2, SAT-3, Asia-1, etc. It is polyvirulent, epitheliotropic, and affects epithelial cells and tissues. The persistence of the virus depends on the environment in which it is found. Dried foot-and-mouth lymph on paper cloth (in a room), on glass (in a stall) retains its virulence for 5-7 days, and dried in sand and stored in the open air turned out to be virulent on the 2nd day. At a temperature of 600C, the virus dies within 5-15 minutes, and at 800C - almost immediately. FMD lymph frozen at -15C remains active for up to 2 years, and dried and frozen for up to 52 months. The virus dies in sour milk; when milk is heated to 85C, it is destroyed within 1 minute, at 80C - after 3 minutes, at 75C - after 15 minutes, at 70C - after 30 minutes. A 1-2% solution of caustic soda or caustic potassium is very destructive for the virus - they are especially effective when hot. PRE-MORTEM DIAGNOSTICS. The most typical signs of the disease are expressed in adult cattle. In lambs, calves and piglets they may be less typical. Foot and mouth disease can be benign or malignant. Patients note: increased temperature, redness of the mucous membrane of the oral cavity and conjunctiva, impaired chewing of gum, dry nasal mucosa, and soon profuse salivation appears, which is accompanied by grinding of teeth and a characteristic “smacking” sound. Swelling and increased sensitivity are noticeable on the skin of the hoof crown and inter-hoof cleft. After 3 days, round or oblong aphthae are found in the oral cavity. They can also be on the nasal speculum. Papules, and then blisters the size of a pigeon's egg, form on the corolla and in the arch of the interhoof fissure. Aphthae can also be located on the skin of the udder nipples. After 1-3 days, the aphthae burst and in their place irregularly shaped erosions with torn edges of different sizes are visible. Sticky saliva comes out of the mouth. In pigs, foot and mouth disease occurs with the formation of aphthae on the snout, on the skin of the udder and on the corolla. In sheep, foot and mouth disease is much milder than in cattle. The most consistent symptom is high temperature. Aphthae formed in the oral cavity, as a rule, go unnoticed. If the corolla or arch of the interhoof fissure is affected, lameness is observed. POST-MORTEM DIAGNOSTICS. The presence of aphthae in the oral cavity, on the udder and limbs is typical. Sometimes aphthae and erosions occur on the mucous membrane of the scar and book. When the process is generalized, local inflammatory changes are found in the thigh muscles; pulmonary emphysema and abomasal edema are noted. In young animals with foot and mouth disease, catarrh of the upper respiratory tract, acute catarrh is found gastrointestinal tract. The mesenteric lymph nodes are enlarged, the mucous membrane of the lips and gums is swollen, reddened, and there are small yellowish nodules and yellowish-gray scabs on it. The common, most characteristic pathological changes in foot and mouth disease are severe exanthema, in severe cases - gangrenous tissue breakdown, most often on the extremities. In certain animal species these changes manifest themselves as follows. In cattle, the mucous membrane of the inner surface of the lips, gums, and tongue is reddened; single or numerous blisters (aphthae) are found on its surface. different sizes - from a pea to a nut, containing a clear or cloudy liquid (lymph). In the place of the burst blisters, intense pink or covered with a yellow-gray coating of erosion is found - small bleeding ulcers. With complications, erosion of the oral mucosa turns into ulcers covered with purulent-ichorous secretion. Inflammatory swelling is noticeable around the ulcers. Rarely, foot-and-mouth lesions are observed in the upper respiratory tract, and bronchopneumonia is possible. Nodules and deposits of fibrinous films are found on the heart valves. In the malignant form of foot and mouth disease, the cavities of the heart are enlarged, the heart muscle is flabby, easily torn, yellowish or gray-white stripes and “tiger heart” spots are visible on the cut surface of the muscle. The spleen is enlarged and softened. The liver is dark brown or spotted clay color, flabby, soft. Lymph nodes (bronchial, mediastinal, portal) are enlarged, flabby, juicy; A whitish-gray mass is scraped off from the cut surface of the nodes. Purulent foci of metastatic origin are sometimes found in parenchymal organs. The mucous membrane of the small intestine is dotted with pinpoint hemorrhages or diffusely reddened, sometimes erosions and ulcers are found on its surface. The buds are dark red or gray-clay in color, there is no border between the cortical and medulla layers. On the rim of the hooves, the crumbs and on the wall of the interhoof gap there are bubbles of varying sizes (from pea to nut size), containing initially clear and then cloudy liquid. The areas where the blisters have opened are covered with a scab, under which a bright red bleeding surface is visible. With the development of the foot-and-mouth disease process in the area of the coronary or fetlock joints, purulent-ichorous inflammation is observed, accompanied by gangrenous disintegration of the deep tissues and exposure of the joint cavity. In this case, as a rule, metastatic pneumonia is noted. Blisters, erosions or ulcers covered with scabs are found on the udder nipples. The udder is compacted, reddened; aphthae and erosions are also found on it. In severe cases, yellowish or whitish-gray spots or streaks occur in the skeletal muscle, causing the muscle to resemble fish flesh; intermuscular tissue is infiltrated. The lymph nodes of the carcass are juicy and enlarged (hyperplastic). Sheep and goats have swollen lips, cheeks and throats. On the mucous membrane of the oral cavity there are transparent or cloudy aphthae the size of a lentil grain or more. The crown of the hoof and the walls of the interhoof fissure are often affected (purulent inflammation and gangrenous decay). Exanthematous lesions are found on the udder and labia. In pigs, blisters of various sizes and ulcers covered with wet or dry scab are found on the snout. Lips and gums are swollen. The mucous membrane of the tongue, oral cavity and pharynx is reddened, there are blisters and small ulcers covered with a soft gray scab. On the crown of the hooves, the crumbs, and on the walls between the hooves there is a bright pink or dark red swelling, clearly visible in white pigs. In severe cases of foot-and-mouth disease, purulent inflammation of the joints with gangrenous tissue breakdown and metastatic pneumonia are observed. The skeletal muscles are flabby, and pale yellowish or grayish streaking is noticeable on the cut surface. The lymph nodes of the carcass are juicy, enlarged - hyperplastic, but sometimes without changes. DIFFERENTIAL DIAGNOSTICS. The pathological picture of foot-and-mouth disease is similar to rinderpest, smallpox, stomatitis, burns of the mucous membrane of the lips and walls of the oral cavity, malignant catarrhal fever of cattle and other diseases. These diseases are differentiated according to the following characteristics. With plague, diffuse hemorrhagic inflammation of the intestine is observed; the limbs are never affected, whereas in foot and mouth disease they are always affected. With smallpox, the udder, nipples, and sometimes the outer surfaces of the lips are affected; the limbs are not affected. In case of malignant catarrhal fever, ichorous-purulent rhinitis and croup-neurotic deposits are found on the inner surface of the lips, gums, on the root of the tongue and the mucous membrane of the pharynx, but no blisters, erosions and inflammations are found on the extremities. With stomatitis, blisters and ulcers occur only in the oral cavity, but they are small, yellowish or grayish in color; There are no large blisters filled with lymph or lesions on the extremities. VETERINARY AND SANITARY ASSESSMENT. It is prohibited to slaughter sick or suspected animals for meat during the first cases of the disease in a safe area. They must be destroyed. In other cases, the slaughter of such animals for meat is permitted, but the release of slaughter products in raw form is prohibited. Meat and other products obtained from the slaughter of animals sick or suspected of having foot-and-mouth disease are used for the production of boiled or boiled-smoked sausages, for cooked culinary products or for canned food. If it is impossible to process meat in this way, slaughter products are rendered harmless by boiling. In the presence of multiple or extensive necrotic foci in many muscles (pelvic and thoracic limbs, annoneuses, etc. ), as well as in complicated forms of foot and mouth disease, accompanied by gangrenous or purulent inflammation of the udder, limbs and other organs, the carcass and other slaughter products are sent for disposal. If there are single necrotic foci in the muscles, the affected areas of the muscles are disposed of, and the question of how to use other slaughter products (remaining parts of the carcass, internal organs) is decided depending on the results of bacteriological examination. When salmonella are isolated, the slaughter products are boiled; if not, they are used for boiled or boiled-smoked sausages. If a batch of animals being handed over for slaughter is found to be sick or suspected of having foot-and-mouth disease, the entire batch of animals is immediately sent for slaughter to a sanitary slaughterhouse. If it is impossible to process these cattle in a sanitary slaughterhouse, slaughter is carried out in the general hall of the slaughterhouse. Carcasses and all other products obtained from the slaughter of animals that have recovered from foot-and-mouth disease and sent for slaughter before the expiration of 3 months after recovery from the disease and the lifting of quarantine from the farm, as well as animals inoculated with an inactivated vaccine against foot-and-mouth disease for 21 days in areas unaffected by foot-and-mouth disease, are released without restrictions, but they are not allowed to be exported outside the region, territory, republic. If more than 3 months have passed since the quarantine was lifted from the farm, animals that have recovered from foot-and-mouth disease are allowed to be sent to a slaughterhouse, and meat and other slaughter products in this case are sold without restrictions, but only within the country. During the forced slaughter of animals with foot-and-mouth disease on the farm, meat and slaughter products are used only after boiling and strictly within the farm. Exporting them in raw form outside the farm is prohibited. Skins, horns, hooves, hair and bristles must be disinfected. VETERINARY AND SANITARY MEASURES AT THE Slaughterhouse ENTERPRISE. Animals from farms unaffected by foot-and-mouth disease within the quarantine zone adjacent to the slaughterhouse are allowed for slaughter, but they are delivered to the enterprise in specially equipped vehicles; Before sending animals from such a farm, their skin and hooves are sanitized. If foot-and-mouth disease is detected at a slaughterhouse, the reception of livestock is stopped and the entire batch of sick animals is sent for slaughter; The meat obtained from them is considered conditionally suitable. If a bunch of cattle or other animals are delivered to the slaughterhouse, among which there are patients with foot-and-mouth disease, then, depending on the clinical signs of the disease and temperature data, the entire batch of animals is divided into two groups: 1) animals with clinical signs of foot-and-mouth disease and those suspected of the disease; 2) animals that do not have clinical signs of foot and mouth disease, with a normal temperature, but are suspected of infection, since they were in contact with patients. The first group of animals is immediately sent to a sanitary slaughterhouse or, if the latter is not available, to a slaughterhouse, separated from healthy animals. To prevent the spread of infection, animals from the second group are also killed in a separate batch without overexposure. The service personnel of the livestock raw material base should only be in the given premises assigned to them. The pens where the animals were kept, as well as the cutting rooms and their equipment, are thoroughly mechanically cleaned and disinfected with a 1-2% hot solution of caustic soda or caustic potassium every day after processing a batch of foot-and-mouth disease cattle. All manure accumulated at the enterprise during the epizootic is neutralized biothermally in specially designated manure storage facilities, according to the instructions for combating foot-and-mouth disease. Workers assigned to service animals must leave the territory of the cattle station through certain access gates. Unauthorized persons are not allowed to enter the territory of the slaughterhouse at this time. The overalls of workers who have had contact with sick animals or their raw products are sent to the laundry for treatment, and the safety shoes are rendered harmless with a 0.5-1% alkali solution. 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Veterinary and sanitary examination of carcasses and organsin case of forced slaughter of animals

Forced slaughter means the deprivation of life of a sick animal due to the inexpediency or ineffectiveness of its further treatment in order to prevent death. Forced slaughter of livestock in meat processing plants is carried out only in a sanitary slaughterhouse. Permission for forced slaughter is given by a veterinarian or paramedic, and a report is drawn up.

Cases of forced slaughter do not include:

1) slaughter of clinically healthy animals with normal body temperature that cannot be fattened to the required standards; those lagging behind in growth and development; barren; low productivity;

2) slaughter of healthy animals that are in danger of death and which are forced to be killed as a result of a natural disaster (flood, earthquake, snow drifts on winter pastures, etc.);

3) slaughter of healthy animals that were injured before slaughter at a meat processing plant, slaughterhouse, slaughterhouse or slaughterhouse.

When deciding on forced slaughter, it is necessary to clearly understand the diseases and other conditions in which the slaughter of animals for meat is prohibited.

The following are not subject to slaughter for meat:

1) Animals sick and suspected of having anthrax, emphysematous carbuncle, rinderpest, camel plague, rabies, tetanus, malignant edema, bradzot, enterotoxemia of sheep, bluetongue of cattle and sheep (blue tongue), African swine fever , tularemia, botulism, glanders, epizootic lymphangitis, meliodosis (false glanders), myxomatosis and hemorrhagic disease of rabbits, avian influenza. If for some reason (latent period, oversight, etc.) the animal was killed with these diseases, then the slaughter products are subject to destruction (burning). It is allowed to use Bekkeri pits for these purposes;

2) Animals that are in an atonal state, regardless of the reasons that caused this state. The atonal state is characterized by a sharp decline in cardiac activity, absence of reflexes to irritation, clouding of the cornea, a decrease in body temperature by 1-2°C and is diagnosed by a veterinarian or paramedic. An animal killed in agony is considered a corpse and must be disposed of or destroyed depending on the disease that caused the condition;

3) Young animals for slaughter (calves, piglets, lambs, kids, etc.), less than 2 weeks of age. If animals are slaughtered before this period, all slaughter products are disposed of;

4) Animals within the first 14 days after vaccination with anthrax vaccines or treated with anthrax serum and within 21 days after vaccination against foot-and-mouth disease in areas unaffected by this disease. In some cases, with the permission of a veterinarian, it is possible to slaughter them earlier than the specified period, provided that the animals had a normal temperature and there were no reactions (complications) to the vaccination. The carcasses of these animals are subjected to bacteriological and physicochemical studies. The meat of such animals is subjected to neutralization depending on the results laboratory analysis;

5) Single-hoofed animals (horses, mules, donkeys, etc.), not subjected to malleinization at a meat processing plant or slaughterhouse. If they are slaughtered without pre-slaughter malleinization, the carcasses and all other slaughter products are sent for disposal. At the slaughterhouse, single-hoofed animals and camels are examined for glanders using a single ophthalmomalleinization method. An animal that reacts to mallein must be destroyed;

6) Animals for 30 days, and poultry - 10 days after the last feeding of fish, fish waste or fish meal. When animals are slaughtered earlier than these dates, carcasses and internal organs have a distinct fishy odor. They are disposed of;

7) Animals that were treated with antibiotics for therapeutic and prophylactic purposes during the period specified in the “Manual on the use of antibiotics in veterinary medicine”; 8) Animals treated with pesticides, before the expiration of the periods specified in the “List of chemicals recommended for treating farm animals against insects and ticks” and the period of restrictions in accordance with the instructions for their use.

Animals that are clinically sick with brucellosis and tuberculosis, with an unknown diagnosis of the disease, or with low or high body temperature cannot be sent to the slaughterhouse; a bird sick with psittacosis, influenza, or Newcastle disease. In case of diseases other than those mentioned above, as well as invasive and non-contagious diseases, poisoning, burns, injuries, fractures, etc., which threaten the life of the animal or require long-term and economically unjustified treatment, forced slaughter is allowed. In the event of forced slaughter on a farm of animals that have recovered from foot-and-mouth disease and were killed before 3 months after recovery from the disease, as well as those vaccinated against foot-and-mouth disease and killed before 21 days after vaccination, carcasses and other slaughter products are used within the farm without restrictions. They are not allowed to be exported outside the region, territory, or republic. Within the republic, these products can be exported to other regions, but only with the permission of the republican veterinary authorities. If more than 3 months have passed since the quarantine was lifted from the farm, animals that have recovered from foot-and-mouth disease are allowed to be sent to a slaughterhouse, and meat and other slaughter products are sold without restrictions within the country. The origin of meat from a corpse, sick or killed in an agonal state can be determined by organoleptic and laboratory indicators.

Organoleptic indicators.

External signs that should be taken into account when identifying the meat of a dead, sick or agonized animal are the following: the condition of the stabbing site, the degree of bleeding of the carcass, the presence of hypostases and changes in the lymph nodes. In addition, it is necessary to carry out a cooking test.

Condition of the stabbing site.

In an animal killed in a normal physiological state, the cut site is uneven and largely saturated with blood. In an animal killed in a seriously ill or agonal state, butchered after death, the cut site is almost flat and less saturated with blood. However, if the cut area is well cleaned or chopped off, then this indicator is not taken into account.

The degree of bleeding of the carcass.

Define different ways: visually establish the presence of blood in large vessels under the serous membranes (pleura, peritoneum); look for the presence of blood in muscle sections under a microscope; a hemoglobin peroxidase test is performed (according to Schonberg, Roeder, I. S. Zagaevsky). The first method is the most acceptable and easy to implement, since the others require some time and laboratory equipment. The degree of bleeding depends not only on the physiological state of the animal, but also on other factors (method of stunning, method of bleeding, incomplete transection of blood vessels, etc.). With the vertical method, bleeding is better than with the horizontal one. With horizontal bleeding, part of the blood remains on the side on which the animal lies. There are four degrees of bleeding: good, fair, bad and very bad. With good bleeding, there is no blood in the muscles and blood vessels, small vessels under the pleura and peritoneum are not visible, which indicates that the meat comes from a healthy animal. With satisfactory bleeding, a small amount of blood is found in large blood vessels; There is no blood in the muscles or appears in small droplets when pressing on the cut surface. From the side of the pleura and peritoneum, the vessels are weakly visible. Satisfactory bleeding is observed in old, emaciated and overworked animals. If bleeding is poor, drops of blood appear on the muscle incision; blood remains are observed in large vessels; from the side of the pleura and peritoneum are clearly visible blood vessels. When pressing on the surface of the muscle incision, dark droplets of blood appear. As a rule, the carcasses of sick animals or those killed in an agonal state are poorly bled. With very poor bleeding, large and small blood vessels are filled with blood; the vessels under the pleura and peritoneum are injected with blood, the surface of the pleura and peritoneum is violet-red; When a muscle is cut, blood flows out. Carcasses of animals killed in a severe pathological or agonal state are always poorly bled.

Presence of hypostases.

Hypostases are areas of tissue soaked in blood. In sick animals, the blood first stagnates, and then, due to an increase in the diversity of the vessels, it flows beyond their limits and stains areas of the surrounding tissue blue-red. Hypostases are observed in corpses, carcasses of seriously ill animals and animals killed in an agonal state. As a rule, they are located on the side on which the animal lay. Therefore, during a veterinary and sanitary inspection, carcasses are turned over to the other side. Changes in the lymph nodes. In the carcasses of healthy and timely dressed animals, the cut surface of the lymph nodes is light gray or slightly yellow. In sick animals killed in agony, the lymph nodes on the cut are lilac-pink in color. The reason for this is blood accumulated in the small vessels of the lymph node, which penetrates through the walls of the vessels into the sinuses and stains it in pink color. Inhibition of oxidative processes in the body of sick animals leads to the accumulation of carbon dioxide, which causes cyanotic (bluish) staining of tissues. Depending on the disease, pathological changes in the lymph nodes are of a varied nature: enlargement, hyperemia, edema, hemorrhage, atrophy, tuberculous granuloma, cysticercosis, actinomycosis, etc. Cooking test. During veterinary examination of meat at food markets, it is necessary to carry out a cooking test. It allows you to determine the origin of meat from animals that have been treated with medications (the smell of medications). In addition, this test allows you to determine the smell of meat from late castrated individuals (bull, bull - the smell of decomposing urine; boar - the smell of rotten garlic). When meat spoils, the cooking test allows you to identify foreign odors (musty, putrid, etc.). The organoleptic method is subjective. In some cases, it is not always possible to establish the origin of meat from a sick animal (for example, in acute tympany, acute infectious diseases, acute poisoning, etc.).

Laboratory research.

According to the “Rules for the veterinary examination of slaughter animals and the veterinary and sanitary examination of meat and meat products” (1983), in case of forced slaughter, regardless of the reason, bacteriological and physicochemical studies are carried out. If necessary, resort to toxicological analysis.

Bacteriocopy.

To determine the contamination of meat with microflora and identify pathogens of acute infectious diseases, bacterioscopy of fingerprint smears from the deep layers of muscles, internal organs and lymph nodes is carried out. Bacterioscopy should precede physical and chemical examination. In fingerprint smears from the deep layers of meat, internal organs and lymph nodes of healthy animals, there is no microflora. Cocci or rods are found in the meat and internal organs of sick animals. In a veterinary laboratory, after bacterioscopy, culture is carried out on nutrient media, followed by identification of the grown culture.

For bacteriological examination the following is sent to the veterinary laboratory:

1) Two muscle samples - a part of the flexor or extensor of the fore or hind limb or a piece of another muscle along with the covering fascia measuring at least 8x6x6 cm;

2) Lymph nodes (at least two); The lymph nodes are taken entirely along with the surrounding connective and adipose tissue. In addition, the mandibular lymph node is sent from pigs;

3) Internal organs - the entire spleen and kidney, a lobe of the liver with a hepatic lymph node and an emptied gall bladder; the cut surface of the liver lobe is cauterized until a scab forms;

4) Tubular bone (sent to clarify the diagnosis in order to isolate a more pure culture of the pathogen);

5) Changed tissue areas. For physical and chemical research, a piece of muscle weighing at least 200 g is sent to the veterinary laboratory. After taking and sending samples, the carcass and internal organs are placed in an isolated room and stored at a temperature of 0-4°C until a response is received on the results of the bacteriological analysis.

Determination of pH.

The pH value of meat depends on the glycogen content in it at the time of slaughter of the animal, as well as the activity of intramuscular enzymes. During the life of the animal, the reaction of the muscle environment is slightly alkaline or neutral. After slaughter, during the fermentation process of meat from healthy animals, a sharp shift in the concentration of hydrogen ions occurs in the acidic direction. So, after a day the pH drops to 5.6-5.8. In the meat of animals that are sick or killed in an atonal state, such a sharp decrease in pH does not occur. Meat from sick and overworked animals has a pH in the range of 6.3-6.5; healthy meat - 5.7-6.2. pH is determined potentiometrically.

Reaction on peroxidase (benzidinosample).

The essence of the reaction is that the peroxidase enzyme found in meat decomposes hydrogen peroxide to form oxygen, which oxidizes benzidine. In this case, paraquinone diimide is formed, which, with underoxidized benzidine, produces a blue-green compound that turns brown after a few minutes. Peroxidase activity is important. In the meat of healthy animals it is very active; in the meat of sick animals and those killed in an atonal state, its activity is significantly reduced. The activity of peroxidase depends on the pH of the medium, although complete correspondence between the readings of the benzidine reaction and the concentration of hydrogen ions is not observed. At a pH of concentrated extracts (1:4) below 6.0, the result of the reaction with benzidine is in most cases positive, at a pH of 6.1-6.2 it is doubtful, and at a pH above 6.2 it is negative.

Formol test (according to G.V. Kolobolotsky and E.V. Kiselev).

In case of severe diseases during the animal's life, intermediate products of protein metabolism - polypeptides, peptides, peptones, amino acids, etc. - accumulate in the muscles in significant quantities. The essence of this reaction is the precipitation of these products with formaldehyde. To perform the test, an aqueous extract from meat is required in a 1:1 ratio. The extract obtained from the meat of an animal killed in agony, seriously ill or butchered after death turns into a dense clot; flakes fall out from the meat of a sick animal in the extract; the extract from the meat of a healthy animal remains transparent or becomes cloudy. Meat is considered to be obtained from a healthy animal if there are good organoleptic characteristics of the carcass, the absence of pathogenic microbes, pH 5.7-6.2, a positive reaction to peroxidase and a negative formol reaction. The meat of a sick or overworked animal is not sufficiently bled, pH 6.3-6.5, the reaction to peroxidase is negative, and the formol test is positive (flakes). The meat of an animal killed in a state of agony is poorly bled, with a bluish or lilac-pink color of the lymph nodes, pH 6.6 or higher, the reaction to peroxidase is negative, and the formol reaction is accompanied by the formation of a jelly-like clot. Veterinary and sanitary assessment. If, according to the results of bacteriological and physical-chemical studies, meat and other slaughter products are found suitable for food purposes, then they are sent for boiling or for the production of meat loaves or canned food. The sale of meat from forced slaughter animals in food markets is prohibited. Release of such meat and other slaughter products, regardless of the results of laboratory analysis, in raw form, including online Catering(canteens, cafes, etc.), without prior neutralization is prohibited. If infectious diseases are determined by laboratory research, for which animals are not allowed to be slaughtered, the carcass along with the skin is destroyed. Carry out veterinary and sanitary measures provided for by the relevant instructions. If pathogens of infectious diseases are detected in slaughter products, the carcass and internal organs are used according to current rules. If salmonella is found in the carcass or organs, the internal organs are disposed of, and the meat is sent for boiling, processing into meat loaves or canned food. If E. coli is detected in muscle tissue or lymph nodes, the meat is sent for processing into boiled or boiled-smoked sausage. When E. coli is isolated only from internal organs, the latter are boiled and the carcasses are released without restrictions. If bacteria of the coccal group, as well as putrefactive microbes (especially from the Proteus group), are detected in the deep layers of the muscles or lymph nodes, but with good organoleptic characteristics, the meat is sent for boiling or for processing into meat loaves. If organoleptic indicators indicate putrefactive decomposition of meat and meat products or if there is an unusual smell that does not disappear when tested by cooking, such meat and meat products are sent for disposal or destroyed. Until the results of bacteriological examination are obtained, meat and offal must be stored in isolated conditions at a temperature not exceeding 4°C. forced slaughter of livestock veterinary

Organization of forced slaughter.

Processing of sick animals is carried out in accordance with veterinary legislation at meat processing plants. Delivery of sick animals to a meat processing plant for immediate processing is carried out in compliance with the relevant veterinary and sanitary rules under the supervision of a veterinary specialist according to a pre-agreed schedule within a strictly established period. These days, healthy cattle are not accepted. According to the requirements of veterinary and sanitary rules, it is prohibited to slaughter animals for meat for food purposes in the cases indicated above. It is allowed to accept animals that react positively to tuberculosis and other chronic infectious diseases, sick or suspected of having contagious and non-contagious diseases, in which slaughter and use of meat and other slaughter products for food purposes is possible without restrictions or after appropriate treatment provided for by veterinary and sanitary rules . The veterinary certificate must provide veterinary and sanitary characteristics of sick livestock sent for slaughter, indicate the date of treatment, vaccinations, cessation of feeding and use of antibiotics for preventive and therapeutic purposes, as well as other indicators limiting the use of animal slaughter products for food purposes. When accepting sick animals, the examination conditions are the same as for healthy ones, but an individual examination is required, and, if necessary, thermometry. During the examination, pay attention to general state animal, dryness of the nasal mucosa in cattle, outer covering, the presence of lameness, edema, ulcers, swelling, wounds, red spots, rashes, scabs. When examining the bird, pay attention to dirtiness, ruffledness and lack of shine of feathers, blue or pale comb or earrings, contamination of feathers in the cloaca area, swelling of the head and earrings, presence of discharge from the eyes and nasal openings, swelling of the joints, paralysis of the legs or wings, drooping belly , exhaustion, etc. In case of incorrect execution of accompanying documents, first of all, a veterinary certificate, suspicion of an acutely infectious morbidity of animals (death during transportation, deviation of the animals’ body temperature from the norm, etc.), etc., the animals are quarantined until the cause is determined. Post-mortem veterinary and sanitary examination and sanitary assessment of carcasses and internal organs of sick animals are carried out in the manner determined by the Rules of Veterinary and Sanitary Examination, taking into account the features characteristic of a particular disease. If, during a post-mortem examination of carcasses and organs, pathological anatomical changes are found that give reason to suspect the presence of infectious diseases, damage to the gastrointestinal tract, diseases of the respiratory organs, purulent nephritis, nephrosis, septicopyemic diseases, pericarditis in pigs, as well as suspected salmonella contamination and other pathogens foodborne diseases carry out bacteriological studies of meat. When conducting an organoleptic examination of slaughter products, it is necessary to carry out a cooking test to identify foreign odors. If, when cooking meat, the broth turns out to be cloudy, with flakes, or has a foreign odor that is not characteristic of meat, additional physical and chemical studies are carried out. They include determining the pH of meat, staging a qualitative reaction to peroxidase and protein breakdown products by reactions with neutral formaldehyde (formol reaction) and a solution of copper sulfate. Meat is considered suitable for food purposes in the absence of pathogenic microbes, the presence of good organoleptic characteristics of the carcass, pH values of 5.6-6.2, a positive reaction to peroxidase and a negative formol reaction and with a solution of copper sulfate. Products from the slaughter of sick animals in their raw form pose a danger to human health or may cause the spread of infectious diseases among animals, therefore they are allowed to be released from the enterprise only after neutralization. The method and procedure for sanitary processing of slaughter products of sick animals is determined by a veterinary expert and is indicated by applying rectangular veterinary stamps to the carcass. Slaughter products are neutralized using high and low temperatures, chemical and other methods. High temperatures are used when boiling meat, processing slaughter products into the production of meat loaves, canned meat, boiled-smoked briskets, loins and sausages. Boiling is the most effective method of detoxifying meat and meat products. The meat is divided into pieces up to 8 cm thick and weighing no more than 2 kg and boiled in open boilers for 3 hours, in closed ones - 2.5 hours. The temperature in the thickness of the pieces must be at least 800C. After cooling, the boiled meat is sent to the sausage shop, where it is used in the production of certain types of sausages. The shelf life of meat after boiling is no more than 1-2 days at 0..+20C. During the cooking process of meat, large losses of raw materials occur: for pork (depending on the fatness category of the carcass) - 35.8-39.7%, for beef - 40-41.3%. It can be seen from this that, along with the high efficiency of neutralization, this method has certain disadvantages: large losses in product weight, restrictions on shelf life and further use of cooked meat. Decontamination of meat products by processing into meat loaves weighing no more than 2.5 kg is carried out in special electric or gas ovens. They are baked at a temperature of at least 1200C for 2-2.5 hours; by the end of processing, the temperature inside the product should be at least 850C. In case of some animal diseases, meat that does not have changes in muscle tissue and in the absence of salmonella is allowed to be processed into boiled sausages. The sausage is cooked at 88-900C for at least 1 hour, the temperature inside the loaf should be 750C. Pork can be used to make boiled-smoked briskets and loins. Breasts are cooked at 89-900C for at least 1.5 hours, loins - 1 hour 50 minutes, in the thickness of the product the temperature should be brought to 800C. The meat of sick animals, approved for the production of boiled and boiled-smoked sausages, as well as if salmonella is detected in the meat, is allowed to be processed into canned food. The technological instructions for the production of canned food provide for temperature conditions that ensure reliable sterilization of raw materials. For example, the sterilization mode for can No. 12 “Stewed beef” is (20-105-20)/ 115, where the first number (“20”) is the duration (in minutes) of temperature rise in the autoclave, the third is (“20”) - duration of steam release, the second (“105”) - duration of sterilization itself; the denominator (“115”) is the temperature at which sterilization is performed. Meat affected by cysticercosis is neutralized by freezing or salting. Pig meat is frozen by bringing the temperature in the muscle mass to -120C and kept for 4 days. Cattle meat is frozen to -120C without further aging. Before rendering harmless by salting, the meat is cut into pieces weighing no more than 2.5 kg and rubbed with table salt (10% of the meat mass), then filled with brine with a concentration of at least 24% and kept for 20 days at 240C, reaching a salt concentration in the depths of the muscles of at least 5, 5%. A report signed by a veterinarian must be drawn up on the reasons for the forced slaughter of animals. At a meat processing plant, animals are accepted for forced slaughter out of turn, and pre-slaughter holding is excluded. If the results of laboratory tests are favorable, the products of forced slaughter of animals with accompanying documents are sent to meat processing plants. Meat from killed sheep, pigs and calves must be delivered in whole carcasses, and beef meat - in whole carcasses or divided into half-carcasses and quarters, which are tagged to determine whether they belong to the same carcass. Such meat is accepted by meat processing plants only upon presentation of an act indicating the reasons for the forced slaughter of the animal, signed by the farm’s veterinarian, a veterinary certificate Form No. 2 and a conclusion from a veterinary laboratory for bacteriological and radiometric control. When accepting carcasses of meat from forcedly slaughtered animals, specialists pay attention to the presence and correctness of accompanying documents and the organoleptic characteristics of meat and offal. Then samples are taken for repeated laboratory testing for the presence of the causative agent of anthrax and salmonella, and in case of disagreement about freshness or suspicion of slaughter of an animal in an agonal state - for physicochemical analyzes. During an organoleptic examination, the following signs are found in the carcass of an animal killed in an agonal state: the stabbing site is smooth, even, the surrounding muscle tissue is not soaked in blood; the blood filling of the saphenous veins and small vessels of the connective and adipose tissue is pronounced, the pleural vessels are noticeably filled with blood, especially those located on the posterior edge of the ribs; muscles are dark red with a bluish tint; pinkish fat deposits; on a longitudinal section of the muscles, there is significant blood filling of the vessels, from which drops of blood appear on the section when pressed, the surface of the section is sticky; lymph nodes are hyperemic; the vertebrae of the severed spine are diffusely dark red; in the subcutaneous tissue and muscles of various parts of the carcass of an animal killed in agony or bled after death, hypostases are found, especially on the side on which the animal lay; hypostases can also be found in paired organs (lungs, kidneys).

During an organoleptic examination, a cooking test must be carried out to identify foreign odors that are not characteristic of meat. Biochemical research includes determining the pH of meat, setting up a qualitative reaction to peroxidase, and cattle meat is also examined by reaction with neutral formaldehyde (formol reaction) and with a solution of copper sulfate. Before determining these indicators, the meat must mature for 20-24 hours. Meat is allowed for food purposes if there are satisfactory organoleptic characteristics of the carcass, the absence of pathogenic microbes, pH up to 6.2, a positive reaction to peroxidase and a negative reaction with a solution of copper sulfate. If, according to the results of post-mortem examination, bacteriological, biochemical, toxicological and other studies, meat and other products of forced slaughter of animals are found suitable for use as food, then, in accordance with the Veterinary Sanitary Examination Rules, they are sent, depending on the production conditions, either for boiling or for the production of meat loaves , or for the production of canned food. The release of this meat in its raw form, including into public catering networks (canteens, etc.) without prior neutralization by boiling is prohibited.

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Topic: Post-mortem veterinary and sanitary examination of organs and carcasses of farm animals.

Purpose of the lesson: Master the post-mortem technique for examining agricultural organs and carcasses. animals.

The lesson is held in the primary processing workshop of a meat processing plant, in the slaughter and cutting department of a slaughterhouse or in the laboratories of a veterinary and sanitary market expert. To work, you need overalls (robe, cap, apron, sleeves, work shoes) and the following tools: knife, fork, musat for guiding the knife blade and a magnifying glass.

Methodology for post-mortem inspection of organs and carcasses of large and small ruminants

Study heads:

The head is separated from the carcass, the tongue is cut at the top and sides so that it falls freely from the submandibular space.

The lips, tongue and mucous membrane of the oral cavity are examined and felt. The tongue is fixed with a fork and cleaned with the back of a knife from food masses and saliva; if there are no visible pathological changes on the tongue, it is not cut.

Lymph nodes are opened

Submandibular- located in the submandibular space between the submandibular salivary gland and the inner surface of the branch of the lower jaw near its angle, behind the vascular notch.

Retropharyngeal middle- located between the pharynx and the flexor muscles of the head at the base of the skull (between the ends of the branches of the hyoid bone). To examine them, a transverse incision is made in the velum palatine, or the tissue between the pharynx and the base of the skull is cut from the aboral side.

Retropharyngeal lateral- located in front and on the side of the atlas wing, under the posterior edge of the parotid salivary gland on the jugular process of the occipital bone. When separated, the heads may be destroyed or remain with the carcass, so the head should be separated so that the cut line passes between the second and third tracheal rings.

Parotid- located below the jaw joint in the notch of the posterior edge of the lower jaw. The posterior half is covered by the parotid salivary gland, the anterior half by the skin. They are usually discovered when masseters are opened.

The masticatory muscles are cut and examined in layers across the entire width, parallel to their surface (external with two cuts, and internal with one) on each side.

Liver research:

The liver consists of lungs with trachea, heart, liver with gallbladder, part of the diaphragm, esophagus.

Lungs - examine from the outside and palpate. The mediastinal and bronchial lymph nodes are opened. The trachea, bronchi and lung parenchyma are examined by making a longitudinal section of each lung along the large bronchi.

Mediastinal lymphatics the nodes are located in the mediastinum between the right and left lungs.

Cranial mediastinal- are located in the precordial mediastinum, in front of the aortic arch, to the left of the esophagus and trachea. When extracted, the livers are often destroyed.

Middle mediastinal- located at the level of the aortic arch on the right. side, dorsally or on the right side of the esophagus.

Caudal mediastinal- located in the posterior part of the mediastinum, caudal to the aortic arch and dorsal to the esophagus, the caudal node from this group almost touches the diaphragm and can reach a size of 12-18 cm.

Bronchial lymph nodes located at the bifurcation of the trachea.

Left bronchial- located under the aortic arch, in the adipose tissue, in front of the root of the left bronchus.

Right bronchial- located on the right at the bifurcation of the trachea, in the notch between the first and second lobes of the right lung, under the pleura. Absent in approximately 25% of animals.

Tracheobronchial lymph node- located in the angle between the apical lobe of the right lung and the trachea.

Heart. The pericardial sac is opened. The condition of the pericardium and epicardium is examined. Then the wall of the right and left parts of the heart is cut along the greater curvature, with simultaneous opening of the ventricles and atria. The myocardium, the condition of the endocardium, heart valves, and blood are examined. 1 - 2 longitudinal and 1 transverse non-through incisions of the heart muscles are made (for cysticercosis, etc.).

Liver. Examine and palpate from the diaphragmatic and visceral sides. In case of accretion of the diaphragm to the liver, the latter is separated and the parenchyma is examined for the presence of pathological changes (abscesses). The portal lymph nodes are cut and examined and 2-3 non-through incisions are made on the visceral side along the bile ducts per 1 presence of fascioliasis.

Portal (liver) lymph nodes 5-8 lie at the gate of the liver, around the portal vein, hepatic artery and bile duct. Covered by the pancreas.

Spleen. They examine it from the outside, and then cut it lengthwise and determine the appearance and consistency of the pulp. In the absence of pathology, the edges of the spleen! should be sharp, and when folding the edges of the cut, they should be free! unite.

To determine the consistency of the pulp, a scraping is made on the incision with a knife. If the scraping is thick, then the pulp is softened.

Kidneys. Removed from the capsule, examined and palpated, and if pathological changes are detected, cut; At the same time, the lymph nodes are opened.

When examining kidneys in the laboratory of veterinary and sanitary examination of the market, they must be opened and the condition of the layers (cortical, border, medulla) and the pelvis examined.

Udder. Carefully palpate and make 2 deep parallel incisions. The superficial inguinal lymph nodes are opened.

Stomach and intestines . Examine from the side of the serous membrane. Several gastric and mesenteric lymph nodes are cut. If necessary, open and examine the mucous membranes.

Gastric lymph nodes located in large numbers along the outer walls of all parts of the stomach, especially in the folds (knots of the rumen, mesh, books, abomasum).

Mesentericlymph nodes located between the parietal layers of the mesentery, forming a long dissected cord, consisting of individual oval-elongated nodes.

Uterus. Testes. Uric bubble . Pancreas. They are examined and, if necessary, opened.

Carcass examination:

The carcass is examined from the surface and from the inside, paying attention to the presence of edema, hemorrhages, neoplasms, bone fractures and other pathological changes. The condition of the pleura and peritoneum is determined. If necessary, examine the lymph nodes from the surface and in the incision, and also cut individual muscles (neck, lumbar, anconeus for cysticercosis), and determine fatness.

According to GOST 779-87, beef and veal meat is divided into the following groups and categories: a) beef from adult livestock (cows, oxen, heifers over 3 years old and bulls), b) beef from first-calf cows; c) beef from young cattle (bulls, castrated bulls and heifers up to 3 years old); d) veal meat.

Carcasses from cows, oxen and heifers over 3 years old are classified asIcategories according to the following indicators (lower limits): the muscles are developed satisfactorily, the spinous processes of the dorsal and lumbar vertebrae, the ischial tuberosities, and the vertebrae do not stand out sharply; subcutaneous fat covers the carcass from the 8th rib to the ischial tuberosities, significant gaps are allowed; The neck, shoulder blades, front ribs and hips, pelvic cavity and groin area have fat deposits in small areas.

Co.IIcategories carcasses are classified when the muscles are less well developed (the thighs have depressions), the spinous processes of the vertebrae, the ischial tuberosities and vertebrae protrude, subcutaneous fat is present in the form of small areas in the area of the ischial tuberosities, lower back and last ribs.

At carcasses from bullsIcategories the muscles are well developed, the scapulocervical and hip parts are convex, the spinous processes of the vertebrae do not protrude, and yII categories the muscles are developed satisfactorily, the scapulocervical and hip parts are not sufficiently developed, the shoulder blades and shoulder blades protrude.

Beef from first-calf cows depending on the fatness and weight of carcasses divided intoIcategory, category if the carcass weight is from 165 kg or more and the muscles are well developed, the shoulder blades are without depressions, the hips are not tucked up, the spinous processes of the vertebrae, the ischial tuberosities and macles may protrude slightly, fat deposits are present at the base of the tail and on the upper inner side of the thighs, as well as on II category, category if the carcass weight is 165 kg or more and the muscles are satisfactorily developed, the hips have depressions, the spinous processes of the vertebrae, the ischial tuberosities and vertebrae protrude clearly, fat deposits may be absent.

Carcasses from young animals(calves, castrated bulls, heifers) depending on weight and fatness are divided into beefIcategories from selected young animals with a carcass weight over 230 kg, class I young animals with a carcass weight over 195 to 230 kg inclusive, class II young animals with a carcass weight over 168 to 195 kg inclusive, class III young animals with a carcass weight of 168 kg or less, when the muscles are well developed , the shoulder blades are without depressions, the hips are not tucked up, the spinous processes of the vertebrae, the ischial tuberosities and vertebrae protrude slightly.

Co.IIcategories carcasses from young animals are classified if the muscles are satisfactorily developed, the hips have depressions, the spinous processes of the vertebrae, the ischial tuberosities and vertebrae protrude clearly.

VealIcategories(from dairy calves) should have the following lower limits of fatness: muscles are developed satisfactorily, pink-milky in color, hips are full, fat deposits are present in the area of the kidneys and pelvic cavity, on the ribs and in places on the hips, the spinous processes of the dorsal and lumbar vertebrae do not protrude .

VealIIcategories(from calves that received additional feeding) - the muscles are less well developed, pink in color, small deposits of fat are present in the kidney and pelvic cavity, as well as in places on the lumbosacral part. The spinous processes of the dorsal and lumbar vertebrae protrude slightly.

Veal is produced in carcasses or in the form of longitudinal half-carcasses, leaving during the carcass tenderloins (internal lumboiliac muscles), kidneys, perinephric and pelvic fat and the thymus gland.

Beef is released for sale in the form of longitudinal sides or quarters, without internal lumbar muscles (tenderloin). There should be no remains of internal organs, blood clots, fimbriae, dirt, bruises or bruises on it. Not allowed for release for sale, but used for industrial processing for food purposes: lean meat, uncastrated bulls (bulls), non-standard processing (with trimming and subcutaneous fat stripping exceeding 15% of the surface of a half or quarter, as well as improper division along the spine , frozen more than once, darkened in the neck area).

General rules of veterinary and sanitary examination. Carcasses of farm animals are delivered to the market chilled. Carcasses can be whole, cut into half carcasses or quarters along with internal parenchymal organs (liver) and heads. Meat in pieces and in frozen form is not allowed for examination and cannot be sold on the market unless it is delivered packaged, packaged and labeled after industrial processing with a set of necessary documents (veterinary certificate form No. 4 or veterinary certificate form No. 2, quality certificate, certificate of conformity , invoice). In carcasses of rabbits and hares on one of the hind limbs for a length

3...4 cm preserve the skin. Carcasses of animals subjected to forced slaughter are not subject to veterinary and sanitary examination and sale on markets.

The following are subject to veterinary and sanitary examination in markets:

meat of slaughtered domestic animals of all types (including poultry and rabbits), as well as meat of game animals and game birds. Internal organs and heads are delivered for inspection along with the carcasses;
meat products (sausage, ham, bacon) manufactured at meat industry enterprises and consumer cooperatives from products belonging to the population, with the presentation of the relevant documents of these organizations;
animal fats in any form. For commercial animal fats, a veterinarian's report must be submitted confirming its origin and type.

The sale of dried meat, minced meat, cutlets, jelly, sausages (blood, liver), brawn, smoked meats, as well as other home-cooked products and semi-finished meat products is not permitted and is not subject to examination.

Veterinary and sanitary examination (VSE) of meat in markets is carried out in a certain sequence. First, they check the documents (veterinary certificates and delivery notes), and also determine the actual availability of the goods. According to the rules of VSE in markets, when delivering carcasses and offal, the owner is required to provide evidence (form No. 2) that the animal was inspected before slaughter, and all slaughter products have passed a preliminary inspection or VSE in full and come from an area free from special conditions. dangerous and quarantine diseases. The issue of product sales is decided both on the basis of inspection data and the results of bacteriological and biochemical research.

Animal meat that has undergone a full VSE and branded is subject to re-examination when delivered for sale to the market. When delivering horse meat, the certificate must indicate that 3 days before the slaughter of the horse, a mallein test was carried out and a negative reaction was obtained.

Meat and meat products exported outside the administrative region can be sold only after presentation of a veterinary certificate, form No. 2.

In order to prevent the sale of meat from sick animals, as well as those with suspected bacterial contamination, a microscopic examination is carried out in the laboratory. If the tissues of the carcass and organs are not in doubt by the veterinarian, then two lymph nodes are taken for microscopy: the superficial cervical and the medial iliac (or knee fold). In pork carcasses, the submandibular lymph nodes are also examined. Smears are Gram stained.

Branding meat at the market. Meat is branded only after complete HSE of animal carcasses and internal organs. The brands are stored by a veterinarian who has received the right to brand meat, under conditions that completely exclude their unauthorized use.

For branding meat, dyes approved by Rospotrebnadzor are used (methyl violet - 8 g, formaldehyde - 80 ml, ether - 120 ml, ethyl alcohol - 800 ml or beet paste with a dry matter content of 40...65% - 750 mg, 2 % solution of tetramethylthionine chloride - 50 ml, 96% ethyl alcohol - 200 ml).

The oval-shaped veterinary mark has three pairs of numbers in the center, the first of which indicates the serial number of the republic within the Russian Federation, the region, the region, the cities of Moscow, St. Petersburg, the second - the serial number of the district and the third - the serial number of the institution, organization, enterprise. At the top of the stamp there is the inscription “ Russian Federation”, at the bottom - “Gosvet-supervision”. The oval stamp confirms that the VSE has been carried out in full and the product is released for food purposes without restrictions. For branding meat of rabbits, poultry and offal, a smaller oval brand is used.

The rectangular veterinary stamp has the imprint “Veterinary Service” at the top, “Preliminary examination” in the center, and three pairs of numbers at the bottom. A rectangular stamp confirms that the meat comes from animals that have undergone pre- and post-mortem inspection and were killed in safe farms. But this mark does not give the right to sell meat without carrying out a full VSE.

A veterinary stamp is placed on the meat of all types of animals: on meat carcasses and half-carcasses, one in the area of each shoulder blade and thigh, on each quarter - one stamp, on offal - one stamp, on rabbit carcasses - two stamps (in the area of the shoulder blade and thighs), on poultry carcasses - one mark on the neck or outer surface of the thigh.

Meat is called muscle tissue along with connective tissue formations, fat, bones, blood and lymphatic vessels, lymph nodes and nerve fibers.

Morphology of meat

The composition of meat includes the main tissues: muscle (muscle), connective (tendons, ligaments, aponeuroses), fat and bone.

Muscle tissue makes up on average 50-60% of meat.

Its color is mainly red, but different types of slaughter animals have different shades from deep red in horses, brick-red small cattle, crimson-red cattle to light or gray-red in pigs. The color depends not only on the type of animal, but also on a number of other reasons. The red color is due to the presence of the protein myoglobin in muscle tissue.

Smell is specific to each animal species. Only frozen meat has no odor.

Consistency - depends on storage conditions; fresh meat has a dense consistency, chilled meat has an elastic consistency, and thawed meat has a flabby consistency.

Taste - this criterion depends on many factors (type, gender, feeding, treatment); normally, boiled meat has an aromatic, pleasant smell.

Morphological structure of muscle tissue. Its structural unit is a nuclear fiber, spindle-shaped, up to 12 mm long and covered on the outside with sarcolemma - an elastic transparent membrane.

Next comes connective tissue. Morphologically these are tendons, ligaments, fascia. All that we call veins. The yield of veins from the weight of the cattle carcass ranges from 9.7 to 12.4%. This tissue consists of a small number of cells and a highly developed intercellular substance, in which fibrous structural elements are located: collagen, elastic and reticular fibers and tissue fluid. Their quantitative ratio determines the structure of the tissue.

Proteins - primarily collagen and elastin - are considered incomplete proteins, as they do not contain the necessary amino acids: tyrosine, cystine, tryptophan. Despite the large proportion of collagen in the product (up to 25%), tissue protein synthesis does not occur in the body of the consumer. In addition, consuming foods containing large amounts of collagen in the form of gelatin also negatively affects kidney function. Elastin is the main protein integral part into the sarcolemma. It makes up about 1% of total meat proteins.

Its digestibility is very low, it cannot be boiled, even with prolonged cooking. Parts of meat rich in elastin (neck, flank) remain tough.

Adipose tissue is a derivative of loose connective tissue, the cells of which are filled with droplets of fat, forming fat cells. A group of fat cells forms fat lobules, or lobes, surrounded by loose connective tissue. There are internal and external (subcutaneous) and intermuscular fat. In cattle, the deposition of subcutaneous fat occurs primarily on the croup, near the rump, etc. When fat is deposited between muscle bundles (mainly in young animals), the meat on the cross section has a marbled pattern. “Marbling” indicates its high commercial, culinary and nutritional qualities.

The amount of adipose tissue in cattle can be from 2 to 25%, in pigs up to 40%. Its biological usefulness depends on the content of vitamins, unsaturated fatty acids and some lipids. If we consider anatomically, the fat of brain and nervous tissue and bone marrow are the most complete in terms of biological properties.

Fats different types animals differ in color, smell, consistency, taste, melting point and solidification point, and other indicators. The usefulness of fat depends on the melting temperature of fat. The lower the melting point of fat, the better it is absorbed. Pork fat and horse meat fat contain highly valuable unsaturated acids (about 10%) and have a low melting point, therefore, they are better absorbed. Lamb and beef fat are refractory - less digestible.

Bone. Its content in the body ranges from 7 to 32%. All bones are divided into tubular and spongy. When boiled, up to 10% fat and 30% gelatin are obtained from tubular ones. From spongy, respectively, 22 - 55%. That is, from the point of view of digestive value, spongy bones are better.

In dry matter bone tissue contains from 26 to 52% organic substances and from 48 to 74% mineral substances. Organic substances are mainly represented by collagen, and mineral substances are calcium phosphate and calcium carbonate, magnesium phosphate, calcium fluoride and other salts.

Chemical composition of meat.

The chemical composition depends on the type of animal, age, sex, fatness, method of fattening and other factors. The main and most nutritionally valuable part of meat is muscle tissue.

The chemical composition of muscle tissue of slaughtered animals is characterized by the following data: water - 70 - 77%; up to 20% proteins and 3 - 10% other substances (lipids, extractives, minerals, vitamins).

Water in muscle tissue is in hydrate-bound and free states. Hydration-bound water makes up 6 - 15% of the mass of muscle tissue, is firmly held by the chemical components of the tissue and is not separated from the cell by ordinary drying. Free water is retained in the tissue due to osmotic pressure and adsorption by cellular elements. Free water is separated from the meat by drying.

Proteins make up up to 87% of all proteins in the body. There are two main groups of proteins: albumins, globulins - this is approximately 90% of all proteins. These groups are characterized by:

A) the content of all the basic amino acids necessary for a person to synthesize proteins in his tissue.
B) have a high degree of digestibility, i.e. are complete proteins.

Lipids. The amount of lipids in muscle tissue depends on the fatness of the animal. The composition of the intramuscular lipid molecule mainly includes high-molecular fatty acids.

Extractives provide the main aroma of meat. Extractive substances are divided into nitrogenous and nitrogen-free.

Nitrogenous substances make up 0.7% of muscle tissue. These include: carnosine, anserine, kartinine, etc., ATP (adenosine triphosphate), ADP, purine bases, individual amino acids, urea.

Nitrogen-free extractives make up: glycogen, more than half; glucose, hexose phosphates, lactic acid, pyruvic acid, etc.

Extractive substances do not contain calories, but their presence in food affects metabolic processes in the body. The meat of an adult animal is richer in extractive substances and has a more pronounced taste than the meat of young animals. Therefore, strong broths can only be obtained from the meat of adult animals. Extractive substances from meat are energetic stimulants of the secretion of gastric glands. Accordingly, strong broths and fried meat stimulate the secretion of digestive juices to the greatest extent. Boiled meat does not have these properties and therefore it is used in the diet for gastritis, ulcers, etc.

Minerals. In raw muscle tissue, the mineral content ranges from 0.8 to 1.8%, in dehydrated muscle tissue from 3.2 to 7.5%. They consist mainly of potassium phosphate, calcium, magnesium and sodium chloride. In total, the body contains 34 micro- and macroelements. Meat is a source of digestible phosphorus (up to 200 mg per 100 g of meat), iron from 3.7 mg% to 6.9 mg%, depending on the type of animal.

Muscle tissue contains various enzymes, hormones and vitamins in quantities necessary for normal fermentation. The vitamin composition contains: B1, B2, B6, PP, B12, pantothenic acid, biotin, A. When meat is cooked, up to 50% of the original amount is destroyed.

Poultry meat.

Poultry meat differs in many respects from the meat of other slaughtered animals. It has more delicate connective tissue, which is evenly distributed throughout the muscle tissue. Tissue fat is also evenly distributed.

The meat of young birds contains less extractive substances than old ones. Therefore, broths obtained from old poultry are not saturated, less concentrated.

However, game meat contains more extractives than poultry. The broth obtained from game meat has a sharp taste. Therefore, it is believed that game is best eaten fried or stewed.

Adipose tissue. Since poultry fat has a low melting point (33-400), it is easily digestible. It also improves both the taste and nutritional value of the bird. Some poultry (geese, ducks) are specially fattened to obtain fat (up to 40-50% of the carcass weight kg).

But we are more often interested in protein; its content in poultry meat is approximately 20%.

Meat color. The muscles in poultry carcasses are distributed unevenly: the mass of the pectoral muscles exceeds the mass of the rest of the body muscles.

The color of poultry meat (chickens, turkeys and other land birds, like rabbit meat) is white in the area of the pectoral muscles, and red in the remaining parts of the carcass; waterfowl (geese, ducks) have brownish meat. White muscles are used for very sharp contractions, red ones for slow ones. There are also differences in chemical composition, in particular for protein. There is more of it in white meat than in red meat. White meat proteins are better digestible (from 15.5 for goose) to 23 for turkey. This is achieved due to less connective tissue compared to other animals. (Poultry meat also contains more calories, from 104 for chicken to 307 for goose.)

Bottom line dietary meat: Poultry fat has a lower melting point, as it contains more unsaturated fatty acids;

-poultry meat contains less connective tissue and has a more tender consistency. In this regard, it is better absorbed by the human body;
-extractive substances, a minimum amount, if the bird is not old and not wild;
-poultry meat contains a large amount of complete proteins. The high nutritional value and biological value of poultry meat is determined by the amino acid composition of proteins.

Meat with deviations from the norm and of sanitary importance.

After the slaughter of an animal, deviations from the norm may be found in its meat, which arise during the life of the animal, and not as a result of storing the meat, as we considered earlier. Let's look at this in more detail.

Weight loss and exhaustion are characterized by a decrease or even absence of fat, both intermuscular and in the natural depot (in the subcutaneous tissue, inside the carcass, etc.). When you lose weight, of course, there can be large fluctuations in the amount of fat. Exhaustion is the highest manifestation of emaciation, resulting from illness, and its signs are strikingly obvious. In this case, in addition to the lack of fat in the carcass, flabbiness and muscle atrophy, as well as a decrease in the liver and spleen, are often noticed. With a severe degree of exhaustion, there is even serous impregnation of the fiber in which fat is usually located (in the subcutaneous, intermuscular, retroperitoneal, perinephric). If the meat of emaciated animals should be excluded from sale in all cases, then the expert should not treat the meat of emaciated animals strictly.

Meat from old animals. Experience shows that the best meat comes from oxen (castrated at 1 year of life) at the age of 4-5-8 years; from pigs up to 1-2 years old and from sheep and rams up to 2-3 years old. Meat obtained from animals much older than this age limit contains little fat, is tough due to the abundance of coarse connective tissue, is difficult to chew, and therefore the market value of such meat is quite low. As mentioned above, the age of an animal is determined by its teeth. If there is no head with the carcass, then by examining the meat alone it is, of course, impossible to form a definite idea about the age of the animal. However, there are some signs that make it possible to a certain extent to identify the meat of an old animal: such meat is dry, dark-colored, poor in fat, this fat is yellow and there is little of it even in natural depots. The meat of a very old animal, due to its indigestibility, low nutritional value, and poor taste, should be considered undesirable for consumption, of low value, but not harmful, and therefore there is no reason to exclude it from free sale. Such meat, through special culinary processing, can even be made tasty. Usually it is mainly used for minced sausages, therefore, it is consumed in highly crushed form, with the addition of various other impurities (seasonings).

Meat of animals that have died or been killed by lightning, drowned, suffocated, driven, died from sunstroke, etc. Animals die either from diseases (mainly of an infectious nature), or from various accidental circumstances, for example, from a broken spine, concussion, drowning, lightning and others. mechanical reasons, suddenly ending life. According to the pre-existing basic Russian legislation, all such animals were treated as carrion, the sale of which in markets was, of course, prohibited. In view of this categorical requirement of our legislation, there is, of course, no need to talk much about meat from dead animals. As we see, such meat must definitely be excluded from consumption. In cases, for example, of death from mechanical causes, when the corpse lay with the entrails not removed (for less than 6 hours) and was then cut up by a butcher, such meat is considered corpse meat and cannot be sold even in the form of cheap (low-value) meat.

Animals that died accidentally (no matter what the reasons) have, first of all, one fundamental difference from animals specifically killed for meat. The former retain all or almost all the blood, while the latter are completely bled dry. Usually, cutting up an animal that has died from accidental causes is not started immediately. Often a significant period of time passes from the moment of death to the start of such cutting, when part of the blood has already coagulated, when hypostasis has had time to form and when, therefore, complete bleeding of the carcass is out of the question. This circumstance forms the basis for the signs by which we recognize meat obtained from dead animals.

This meat is characterized by the following characteristics:

congestion of all internal organs, especially the liver and spleen;

hypostases of serous membranes, for example, costal pleura, parietal peritoneum;

subcutaneous veins overflowing with blood;

the moisture content of the meat, its dark red color, the obvious blood filling of its vessels (wet the fingers with blood when touched); soaking spongy bones with blood;

the absence of a “cut” wound on the neck with blood-infiltrated edges of the wound and its surrounding parts;-

the speed of oncoming decomposition (the processes of meat rotting are significantly accelerated).

These signs will be more pronounced the more blood stagnates in the body, and, conversely, they can be expressed unclearly when animals are slaughtered in agony or butchered immediately after death (especially after exposure to mechanical causes), when it is still possible to release a significant amount of blood and thereby smooth out the signs of natural death. It is also clear that the described signs in small pieces of meat are much more difficult to notice than in carcasses, and even when examining the organs simultaneously, that is, in cases when all the signs can be seen in their entire characteristic totality.

Meat from animals that are forced to be killed. There are cases when a completely healthy animal is suddenly struck by some kind of mechanical force, due to which the animal is crippled, for example, dislocated joints, broken limbs or other serious damage to the body. The prediction for all these accidents is usually so unfavorable that the owner, without hesitation, decides to slaughter the animal for meat, so as not to lose all its value. The same solution occurs in cases where a completely healthy animal suddenly falls ill with colic, volvulus, bloating, etc., or when it cannot give birth due to the incorrect position of the fetus in the uterus, etc. In all such cases, after all hope of cure has disappeared, the owner usually also slaughters the animal for meat.

Since such animals are often delivered to slaughter on carts, this is where the technical term “cart animal” comes from, and the slaughter itself is called “forced.”

If it was previously said regarding the meat of dead animals that it should not be allowed for sale, then the meat of prematurely slaughtered animals is used after bacteriological examination. If salmonellosis is present, the meat is sent to canning production, and if it is absent, it is sent to sausage production. In fact, such animals are almost no different from those that are killed and butchered in industrial slaughter.

Meat of poisoned animals. Animals that are poisoned or treated with any toxic substances before slaughter (for example, strychnine, arsenic, nitrates, antibiotics, etc.) produce meat that is dangerous for consumers. This opinion was confirmed by the results of a qualitative analysis of the meat of poisoned animals, according to which the presence of a known poison in the muscles was detected with certainty. Therefore, it is believed that the meat of poisoned animals can serve as a source of serious illness or even fatal intoxication in humans and animals. This leads to a logical conclusion: the meat of poisoned animals must be excluded from free sale.

For example, the use of large doses of nitrogen fertilizers leads to the accumulation of nitrates and nitrites in the muscle tissue of animals. Such nitrate meat is very easily identified by the boiling test. When boiling, as we have already found out, the meat turns white or gray. However, in the presence of nitrates or nitrites, muscle tissue myoglobin reacts and forms nitrosomyoglobin - a substance that gives meat a pinkish-red to brick-red color depending on the nitrite content (the same as in sausages), so nitrate meat is sold should not do so.

Chickens raised in large poultry farms are given daily antibiotics, high doses of which are deposited in the bone marrow. And since many antibiotics contain a nitroso group, when heated in grilling or cooking, hemoglobin interacts with the nitroso group of the antibiotic and red-colored bone marrow compounds are formed. And if healthy chickens have bones grey colour, then in chickens poisoned with antibiotics, the bones turn cherry-red, and sometimes the adjacent meat tissue is also stained. Eating such chicken meat, poisoned with antibiotics, is strictly prohibited.

It is known, for example, that arsenic belongs to the group of persistent poisons, which, once they get into tissues, are very difficult to destroy there. It is also known that in some areas in the last century there was a custom of giving arsenic to animals (in order to better fatten them) in gradually increasing quantities, reaching huge single doses. A striking example The meat of birds that have received colossal doses of those alkaloids to the action of which they are physiologically insensitive can serve. For example, by feeding chickens strychnine (up to 0.2) for 14 days, researchers obtained meat from them, which was the source of fatal poisoning of a dog.

Meat with inclusions of foreign bodies. In the muscle tissue of killed animals, most often in sheep, foreign bodies are found - feather grass seeds. When sheep stay on pastures during the flowering and fruiting period of feather grass, grains and awns of these plants get into their wool. The spiral-shaped awns, moistened by rain, twist, the grains with a sharp tip and saw-toothed teeth pierce the skin and enter the subcutaneous tissue, muscles and internal organs; when the muscles contract, they penetrate into the deep layers. In case of severe damage to feather grass disease, the death of the animal is possible.

Pre-slaughter examination of affected sheep reveals the following signs: the wool is disheveled and tangled with protruding feather grass awns, the skin areas of the thoracic and pelvic limbs, the abdominal wall and the intermaxillary space are most often affected. In these places the skin is thickened, tight and painful. Lymph nodes (submandibular, superficial cervical, knee fold) are enlarged.

In the skin and subcutaneous tissue, a large number of grains and awns of feather grass are found, surrounded by a dense capsule and abscesses the size of a pigeon egg. The affected muscles are reddened, swollen, the lymph nodes are enlarged, the heart muscle is flabby, serous infiltrates are possible, the liver is enlarged, flabby with a cherry tint. During bacterioscopic examination of affected organs and carcasses, a Salmonella culture is often isolated.

Sanitary assessment. If the carcasses and organs are slightly affected, there are no abscesses, and there are no inflammatory changes in the muscles, then after stripping they proceed without restrictions. In case of severe damage with the presence of abscesses or other inflammatory changes, the carcasses are sent for technical disposal.

Meat with deviations from the norm in smell and taste.

Meat with abnormal smell and taste. It happens that meat, impeccable in appearance, bought in our markets, emits an unpleasant odor or has a nasty taste when preparing a dish from it. Abnormal smell and taste of meat can be caused by four reasons:

a) the influence of gender (sexual smell);
b) the influence of feeding (feed smell);
c) the influence of treating an animal with odorous substances (medicinal odor);
d) the influence of certain pathological processes.

A. The influence of gender. The unpleasant smell of meat is observed only in males who are able to be sexually active. Neutered males and females never produce such meat. There is no doubt, however, that its intensity and specificity are closely related to the genus of the animal and its individual characteristics. The smell of goats, for example, is special, specific, sharp, disgusting (sometimes they say “it smells like a goat”), the smell of wild boars is reminiscent of decaying urine, of bulls - garlic... It is also interesting that the so-called “guts”, i.e. males, whose testicles have not descended into the scrotum, but remain in the abdominal cavity, rarely produce smelly meat. The intensity of sexual odor is also related to personality. The meat of some males has a weak odor, its smell can only be detected when boiled, and, conversely, the meat of other males emits a pungent odor, noticeable already in a piece of raw meat that is in a hot, steamy state. IN the latter case, along with the cooling of the meat, the smell gradually disappears, appearing later when heated. The abnormal smell is most noticeable in food, which is why when testing meat for smell, the so-called cooking test is recommended.

In killed animals (especially pigs), the odor is most pronounced in the submandibular and parotid salivary glands. Therefore, if suspected, the smell can be determined by cutting and examining these organs.

The sexual smell and taste in meat disappears 2-3 weeks after castration, in fat - 2.5 months, and in the salivary glands even later.

Take a flat piece of meat the size of your palm and cook it in clean boiling water for 10-15 minutes. The steam released, as well as the piece of meat itself and the broth obtained from it, emit a specific, unpleasant sexual odor, sometimes noticeable even from a distance.

B. Effect of feeding. When feeding meat animals, shortly before slaughter, various substances that have an unpleasant odor, for example, slops, oil cakes, fish or fish meal, decomposing root crops (turnips, rutabaga, beets) or strong-smelling plants (wormwood, bugs), The result is meat that has an unpleasant taste and smell. Experience shows that such a smell is detected either exclusively during cooking, or even when sniffing already raw meat.

A typical case in this regard is told by M. M. Romanovich. Since 1894, bugs (Lepidium ruderale), thanks to droughts that destroyed the best varieties of grass, filled all pastures in Nikolaev. Animals usually do not eat bedbug because of its smell and pungent, bitter taste, but here, willy-nilly, they had to feed on it. As a result, not only the milk of cows, but also the meat of slaughtered animals began to emit an unpleasant odor. “Already at the entrance to the slaughter chamber,” says M. M. Romanovich, “an unpleasant smell was felt if there was at least one carcass of an animal that had eaten bugs. Kitchen methods of preparing such meat did not destroy, but only intensified the smell of feed. The position of the meat producers was critical, since consumers returned the purchased meat back. The carcass, divided into small pieces and stored for 2-3 days, as well as meat in small pieces, almost lost the described unpleasant quality (the smell was barely noticeable). This state of affairs in Nikolaev continued until 1900, when the number of bugs in the pasture decreased over time.In general, it should be said that feed odor can vary in intensity depending on the quantity and quality of feed eaten by the animals.

B. The effect of treating an animal with odorous drugs.

If an animal receives orally, through the stomach, as a medicinal agent, any pharmacological drug that is distinguished by a sharp, specific and often unpleasant odor, then the meat obtained from such an animal acquires a corresponding taste, clearly detectable during cooking. This flavor is supplied to meat, for example, by carbolic acid, kerosene, creolin, turpentine, cumin, chlorine preparations, camphor, valerian root, sulfuric ether and other agents.

In practical terms, it is also important to know that some of the above-mentioned drugs can give meat an unpleasant taste even in cases where the animal does not ingest them before slaughter, but only has the opportunity to inhale them. In this regard, it is especially worth emphasizing the influence of those agents (for example, chlorine, carbolic acid, creolin, tar) with which wagons used for transporting slaughter cattle are so often disinfected.

It should also be added that completely normal meat stored in areas that are poorly ventilated or have the smell of disinfectants can become saturated with these compounds and acquire a nasty smell and taste.

D. The influence of pathological processes. Various pathological processes can also cause the unpleasant smell and taste of meat and fat.

So, with EMKAR and malignant edema, meat and fat give off a putrid odor or the smell of rancid oil.

With phlegmon, metritis and tympany, the smell of feces is noted, with traumatic purulent pericarditis and peritonitis - the smell of manure or ammonia, with kidney diseases - the smell of urine. If an unusual odor is detected in the meat, then the carcass is kept in an actively ventilated room, and then the smell and taste are determined by cooking. If the smell remains, the carcass is sent for technical disposal. In addition to boiling, a sample of meat can be fried over low heat. To determine foreign odor in fat, rub it thoroughly between your fingers and sniff it or warm it slowly over low heat.

Meat with deviations from the norm in color.

Meat color. Determining color is important in those rare cases when meat obtained from an animal that has died or was slaughtered during its death throes is brought to market. Such meat is usually frozen after processing by the butcher. Since in such cases the blood cannot be sufficiently released from the animal, its meat turns out to be dark red in color, and signs of hypostatic hyperemia are noticed on the parietal pleura and peritoneum on the right or left side. It should, however, be noted that sometimes the described symptoms are not clearly expressed. Sometimes an abnormal yellow color of the fat is observed (lipochromatosis). The reasons may be different: firstly, it is possible in old animals; secondly, a dark yellow (saffron) color occurs with abundant feeding of fresh grass, carrots, corn, rapeseed or flaxseed cakes. This is explained by the accumulation of coloring substances from the lutein group in fat, as well as the deposition of fat-soluble pigments - carotenoids).

The color of the food origin fades after 24 hours of storage of the carcass. When such meat is cooked, the broth becomes clear and emits an aroma. Color caused by these reasons does not affect the sanitary assessment of meat.

Pathological jaundice is observed in a number of diseases accompanied by bile pigments in the blood - bilirubin and biliverdin, and not only fat is stained, but also intermuscular connective tissue, bones, cartilage, serous and mucous membranes (which is a differentiating feature when there are differences in the origin of the color - food or pathological). If doubts still remain as to what caused the coloring, then laboratory tests are carried out for the presence of bilirubin (test with sulfuric acid, alkali NaOH).

More often, in practice, changes in the normal color of meat depend on those hemorrhages and blood soaking that appear as a result of disruption of the integrity of the vessels of muscle tissue. This is observed, for example, with external injuries (blows, bruises, etc.), as a result of which part of the subcutaneous tissue and superficial layers of the muscles become saturated with blood.

With the above-described changes in the normal color of fat and meat, there is a need for partial culling of meat, for example, with hemorrhagic infiltration, depending on traumatic causes (impacts, bruises). In case of severe degrees of jaundice, when all parts of the carcass, 48 hours after slaughter, are still colored yellow or yellow-green, or in the presence of exhaustion, according to existing culling rules, all

the carcass is excluded from sale and sent for disposal.

Sometimes a black or brown-brown color is found in internal organs and carcasses, caused by the deposition of corresponding pigments in the tissues. Black coloring is associated with excessive accumulation of melanin pigment in tissues. Melanin is most often found in cattle and small cattle in the liver, lungs, subcutaneous tissue, and in the membranes of the brain and spinal cord. A generalized form is also possible - when pigmentation is noted on the pleura, peritoneum, fascia, bones, etc.

Individual organs and muscles are sometimes stained with a yellow-grained pigment, giving the meat a striated brown color. This pathological process is called xanthosis.

Sanitary assessment. When colored as food origin, the meat is edible. Meat with a jaundiced color that gives a positive reaction to bilirubin is not used for food. With melanosis, if the pigmentation covers only the organs, they are disposed of, and the carcass is used without restrictions; if the entire carcass is pigmented, then it is disposed of.

Meat from driven, stressed animals.

Pale, watery meat. Sometimes, when clinically healthy animals (most often pigs) are slaughtered, a carcass with pale colored muscle tissue is obtained. The reason for the appearance of this pale, watery meat is that the animals are very excited before slaughter as a result of stress factors. The content of adrenaline in the blood of animals increases, under the influence of which ATP is quickly broken down, which leads to accelerated hydrolysis. After just an hour, the pH in the meat drops to 5.8.

Sometimes the meat at slaughter is dark-colored, dry, and hard. It becomes this way due to prolonged exposure to stress factors on the animal. In addition to all the characteristics described above, it is also distinguished by its stickiness, rapid deterioration and the ability (when crushed) to absorb a significant amount of water. The stickiness of the meat of hunted animals is striking. If you take, for example, even a fairly heavy piece of meat and forcefully throw it at a wall, the piece sticks tightly. Such meat is difficult to cut with a knife. The broth made from such meat will be very cloudy and foamy.

This is due to the fact that in such meat there is practically no glycogen and therefore the processes of meat ripening do not occur in it and the pH of the muscle tissue environment practically does not change. And since after the slaughter of animals, synthesis processes in the body no longer occur, then, in the absence of carbohydrates, the processes of protein decomposition begin. Such meat (PSE, DFD) is often used for the production of sausages.

Sanitary assessment. Due to loss of presentation, the meat is sent to industrial production. processing.

Meat inflated with air. Inflation of meat, mainly calves, piglets, and more recently chickens, is widely practiced by meat traders. This falsification occurs for purely commercial reasons, since inflating, for example, veal carcasses gives them a more plump, beautiful, appetizing appearance, making such carcasses easier to sell for a higher price. A two-week-old poorly fed calf, after inflating, acquires the appearance of a 5-week-old, well-fed calf, and the reddish color of its meat turns white. Thus, thanks to inflation, veal of the 2nd grade can be freely sold for the 1st grade. The inflation operation itself is performed as follows: having made an incision in the skin of a killed animal near the hock (heel) joint, a blunt-ended iron rod is passed under the skin on the inner surface of the metatarsal bone, with which the subcutaneous tissue is torn in various directions. After this, the forger begins, using bicycle, automobile and other types of pumps, to blow air into the fiber until the carcass makes a clear drum sound when tapped. Experience shows that during this operation, air penetrates not only into the subcutaneous, but also into the intermuscular tissue, right down to the meat bundles.

There is no doubt that inflated meat cannot cause much harm to the consumer if the meat is sold by weight, but this falsification is intended to fake the appearance of the meat. In addition, inflation is almost always practiced through a tube with the mouth, when, therefore, it is possible to introduce into the meat a wide variety of representatives of the bacterial flora of saliva, not excluding tubercle bacilli. In addition, inflated meat is fragile: it very soon begins to deteriorate in its entire thickness at the same time, which is understandable if we take into account the mass of saprophytes that is driven into the meat along with atmospheric air.

Recently, meat inflation has become widespread in the sale of chickens. In many markets, chickens are sold not by weight, but by size and appearance. Therefore, meat traders insert a needle under the skin of chickens or into the muscle tissue of the breast and inflate with a pump. As a result, the dead chicken looks like a well-fed chicken. It is quite easy to distinguish such counterfeits. When palpating a chicken or chicken carcass, the meat does not have a dense consistency, but a fluid, easily moving mass.

Coloring and bleaching meat. To give old meat a more attractive appearance, it can be tinted with bright red dyes, such as magenta. To give poultry carcasses a yellow color (which means they are well-fed and fatty), meat traders rub carrots or carrot juice. Sometimes poultry carcasses can be rubbed with other yellow dyes, for example, saffron, food dyes. Probably, many buyers have noticed that there are no “blue” chickens and chickens in our markets. Sellers simply treat chickens with bleach. To do this, the bird carcass is placed in a boiling solution of baking soda for 1-2 seconds. Soda, getting into the subcutaneous layer, increases its volume and the skin becomes opaque and muscle tissue is not visible. Thus, the skin color becomes whiter, and a small layer of subcutaneous fat gives the carcass a noble yellow color.

Adulteration of meat with water or blood. Widespread high-quality falsification of meat. There are several ways.

The meat is placed in water for several hours and its weight can increase up to 25%.

In frozen meat, water or blood is injected using a syringe into the voids formed during freezing. Water is partially stained with blood, and blood in general is an ideal component for such falsification; it freezes and a single frozen whole is obtained. For 10 frozen carcasses, one flask of blood is usually enough. When selling such frozen meat, it is practically impossible to distinguish artificially injected and frozen blood from regular blood. Then, when the consumer begins to defrost such meat at home, the color of the water becomes more red.

They freeze water onto the carcass. To do this, frozen carcasses of meat are poured with water on top. The water freezes and then the ice is sold along with the meat at the price of meat.

To extend the shelf life of meat, especially small-portioned meat, various antibiotics are introduced into it. This allows you to significantly extend the shelf life of meat. Abroad, antibiotics are added to water that is frozen, for example, on animal carcasses, chicken legs, etc. Therefore, as many experts note, even flies do not land on such products.

Veterinary and sanitary examination of milk

Milk is one of the most valuable food products. It contains about 200 substances vital for humans and young animals. The main ones are proteins, fat, milk sugar and mineral salts. Milk proteins contain 20 amino acids, including treptophan, lysine, methionine, lecithin and others, which are essential. Milk contains 25 fatty acids, most of which are unsaturated and therefore easily absorbed by the human body. Milk sugar (lactose) is only slightly fermented in the intestines and is almost completely absorbed. Mineral salts are widely represented in milk: calcium, potassium, sodium, magnesium, phosphorus, sulfur and others, necessary for the normal flow of basic life processes in the body,

In total, milk contains 45 mineral salts and trace elements. Milk contains both fat-soluble vitamins - A, D. E, and water-soluble vitamins - C, P, B1, B2, B6, B12 and others that regulate metabolism. It is very important that the numerous components of milk are in a strictly interconnected relationship, which is important in the life of the body. Pure fresh milk from a healthy cow has bacteriostatic properties. If freshly milked pure milk is cooled to 3-4°, then it retains these properties for up to 1.5 days, and at a temperature of 10° - 24 hours. Lactic acid products made from milk (yogurt, kefir, cottage cheese, etc.) are antagonists of putrefactive intestinal microflora and are irreplaceable as dietary products.

Meanwhile, if the sanitary conditions of milking, primary processing, storage and transportation are violated, as well as if cows become ill, milk can become contaminated with pathogenic and toxigenic microflora, which poses a danger to people and young animals.

Primary processing of milk is carried out in the dairy. The milk obtained during milking is filtered through a strainer with a cotton filter or a filter made of non-woven fabric. To filter milk, use white flannel, waffle or lavsan fabric.

A cotton or non-woven filter is used to strain one flask of milk, after which it is replaced with a new one.

Fabric filters, as they become contaminated with mechanical impurities, are rinsed in running water.

If the above filter materials are not available on the farm, gauze is used.

Milk is filtered through gauze in 4-6 layers, fabric (including lavsan) filters in two layers.

After filtering the entire milk yield, filters made of cotton fabrics are washed in a 0.5% warm solution of desmol or washing powder, rinsed in running water, ironed or boiled for 12-15 minutes and dried. After washing in a solution of detergent powder, filters made of lavsan fabric are immersed for 20 minutes in a freshly prepared 1% solution of sodium hypochlorite or a clarified solution of bleach containing 0.25-0.5% active chlorine, rinsed with water and dried.

Consumption rates for filter materials based on the amount of milk produced are given in the Appendix.

With centralized export of milk, it is provided for cooling and temporary storage on the farm for 12-24 hours, followed by export by specialized transport according to an established schedule. The farm should have enough containers to store morning and evening milk separately.

The milk is cooled to 4-6°C. The temperature of the milk when it is received at the dairy plant should not exceed 10 °C.

When machine milking into a milk line, the milk must be cooled immediately in the flow. When milking in portable buckets, the time interval between milking and the beginning of its cooling should not exceed 16-20 minutes.

The duration of milk storage depends on its temperature (see table).

Shelf life of milk at different refrigeration temperatures

After each milking, before removal from the farm, the milk is cooled, guided by the basic requirements set out in clause 5.2. In addition to milk coolers, you can use ice pools into which flasks of milk are immersed. The milk level in the flasks should be lower than the water level in the cooling container. The lids of the flasks should be open, and the entire pool with the flasks should be covered with clean gauze. To ensure uniform cooling of the milk, it is stirred periodically (every 20-30 minutes) with a clean whorl.

In agreement with dairy industry enterprises and other producers, state veterinary and sanitary inspection bodies, it is allowed to deliver milk without refrigeration within 1 hour after milking. At the same time, the farm must guarantee high sanitary quality of the milk supplied.

To supply children's institutions, only chilled milk of at least grade I according to GOST 13264-70 is allowed, delivered no later than 12 hours after receiving it at the farm.

Milk should be transported to milk collection points or dairies in milk tanks or by dedicated transport in flasks.

The bodies of vehicles used to transport milk in flasks must be clean and free of foreign odors.

It is not allowed to transport milk together with strong-smelling, dusty and toxic substances (gasoline, kerosene, tar, pesticides, cement, chalk, etc.), as well as the use of milk tanks for the transportation of other substances.

Containers used for transporting milk. must be hermetically sealed with lids equipped with sealing gaskets made of rubber or polymer materials approved by the Ministry of Health of the Russian Federation for contact with food products. The use of other materials as sealing gaskets is prohibited.

Tanks and flasks with milk are sealed before shipment. In summer, flasks are filled with milk up to the cap (to avoid shaking and churning of fat during transportation), and in winter, only up to the neck.

To protect milk from heating in the summer and from freezing in winter, the flasks are covered with a clean tarpaulin or other protective materials.

Sampling and preparing them for analysis. When collecting samples for research, it is very important that a proportional amount of milk is taken from each milk yield (average sample). Selection is carried out using a metal tube with a diameter of 8-10 mm after thoroughly mixing the milk in each flask. Before taking a sample, milk in tanks is mixed with a stirrer for 3-4 minutes, and samples are taken from each compartment of the tank. The layer of cream adhering to the walls of the flask is cleaned and mixed with milk. Before taking a sample, the tube is rinsed with the same milk from the flask being tested. The collected samples are poured into a flask.

A full production analysis requires 250 ml of milk. If necessary, milk samples for some studies can be preserved by adding 1 ml of a 10% solution of potassium dichromate for every 100 ml of milk. Canned milk samples can be stored at a temperature of 4-6" for up to 10 days. Samples are stored in clean bottles, closed with stoppers.

The quality of milk is determined in a complex of organoleptic factors. physicochemical, and if milk is suspected of being contaminated with pathogenic microflora and bacteriological studies. Freshly milked milk is characterized by the following organoleptic and physical properties.

ORGANOLEPTIC STUDY OF MILK

Appearance: A homogeneous white liquid with a slightly yellowish tint. The color of milk is determined in a glass cylinder by viewing it in reflected light. Colostrum is yellow or yellow-brown in color. Changes in the color of milk are observed in some diseases of cows. For example, with leptospirosis and some forms of mastitis, the milk has a yellow color. The yellow color of milk is observed when cows are fed large amounts of carrots and corn. Milk becomes reddish when cows are sick with piroplasmosis or pasteurellosis. anthrax and hemorrhagic mastitis, as well as in case of violation of the rules of machine milking, when after the end of milk flow the milking cups are kept on the teats. Feeding cows large quantities of certain plants from the ranunculaceae, milkweed and horsetail families will also give the milk a reddish color. Red or pink milk occurs when pigment bacteria, miraculous rods, etc. develop in it. Therefore, in each case of a change in the color of milk, it is necessary to establish its causes.

The smell of milk is specific. When determining the smell, cold milk is heated in a flask or test tube to a temperature of 25-30°. In cold milk the smell is less recognizable. Good quality milk has a pleasant, specific smell. Milk acquires foreign odors when stored with odorous substances (kerosene, fish, sauerkraut, creolin, etc.). Milk acquires a manure (barn) smell when it is filtered not to the dairy, but in a dirty barn, and also when particles of manure get into the milk. A musty smell appears when freshly milked milk is stored in a tightly closed container. In such cases, putrefactive microorganisms multiply abundantly, hydrolyzing milk proteins. Milk has a silage smell when feeding poor-quality silage to cows, as well as when storing silage in a barnyard.

The taste of milk is pleasant, slightly sweet. To determine the taste, the milk is slightly heated. Then take a sip of milk into your mouth and rinse your mouth with it to the root of your tongue. Some foods can have a negative effect on the taste of milk. For example, radishes, turnips, rutabaga, rapeseed, field mustard, fed in large quantities. Milk has a salty taste at the end of lactation, when mixed with colostrum, with udder tuberculosis and mastitis.

The bitter taste is caused by cows eating a large number of bitter plants: wormwood, lupine, buttercups, burdock, beet tops, turnips, moldy spring straw, and rancid cakes. When storing milk or dairy products for a long time low temperatures cold-resistant microorganisms develop in them, giving milk, cream, sour cream and butter a rancid taste. In this case, the decomposition of milk fat occurs with the formation of butyric acid, aldehydes, ketones and other substances that determine this taste. Milk acquires a soapy (alkaline) taste when it is contaminated with putrefactive bacteria.

The consistency of the milk is homogeneous. It is determined by slowly pouring milk from one container (cylinder, beaker, etc.) to another. An admixture of flakes or clots in the milk indicates a breast disease. Slimy (sticky) milk is caused by certain races of lactic acid streptococci, lactobacilli, etc.

Density. The density of milk is the ratio of its mass at a temperature of 20° to the mass of water of the same volume at 4°. The density of milk characterizes to a certain extent its naturalness. The density of whole milk ranges from 1.027 to 1.033, the average is 1.030. The density of skim milk is within 1.038, with an average of 1.035. When skim milk is added to whole milk, the density of the latter increases, and when water is added, it decreases. Every 10% of water added to milk reduces its density by three divisions of the hydrometer scale, or by 3°. When skim milk is added or fat is removed, the density of the milk increases accordingly. However, if you skim the milk and then add the same amount of water, its density will not change. This kind of falsification is called double. To identify it, it is necessary to determine not only the density of the milk, but also the fat content in it.

The density of milk is determined no earlier than 2 hours after milking and at a temperature not lower than 10° and not higher than 25°. The density of milk is determined with a special milk hydrometer (lactodensimeter) at a temperature of 20°.

Method for determining density: 200 ml of the milk being tested is poured into a glass cylinder and a milk hydrometer (lactodensimeter) is lowered. The reading is made on the scale of a thermometer and a hydrometer. If the temperature of the milk is 20°, then the readings on the hydrometer scale correspond to the actual density. Otherwise, an adjustment is made for temperature. Each degree of deviation from normal temperature (20°) corresponds to an amendment equal to +-0.2 degrees of the hydrometer. At a milk temperature above 20°, the density will be less and the correction is made with a plus sign. When the milk temperature is below 20° - with a minus sign.

Research method: 1 ml of the milk being tested is poured into a test tube, 2 drops of a 10% solution of potassium chromate and 1 ml of a 0.5% solution of silver nitrate are added. The test tube with the contents is shaken. Conditioned milk turns lemon yellow, and milk diluted with water turns brick red.

Determination of ketone bodies in milk. To 5 ml of the milk being tested in a test tube, add 2.5 g of ammonium sulfate. 2 drops of a 5% aqueous solution of sodium nitropruside and one ml of a 25% aqueous solution of ammonia. Shake the test tube and read the reaction after 5 minutes. In the presence of ketone bodies, the mixture becomes pink in color. Such milk is discarded.

DETERMINATION OF THE PERCENTAGE OF FAT IN MILK

Determination of fat in milk is carried out using the sulfuric acid method. It is based on the dissolution of milk proteins with sulfuric acid, as a result of which the fat is released in its pure form. Sulfuric acid with a density of 1.81-1.82 and isoamyl alcohol with a density of 0.811-0.812 are used as a solvent.

Research method: 10 ml of sulfuric acid is poured into a milk butyrometer using an automatic pipette, then 10.77 ml of milk and 1 ml of isoamyl alcohol are carefully added (along the wall). The butyrometer is closed with a rubber stopper, wrapped in a towel and gently stirred until the contents are completely dissolved. Then the butyrometers are placed with the stopper down and in a water bath at a temperature of 65-70° for 5 minutes. The butyrometer removed from the bath is centrifuged for 5 minutes. After centrifugation, the sheaf is placed in a water bath for 5 minutes, after which the amount of fat is measured on the butyrometer scale. Each large division corresponds to 1% fat, and each small division corresponds to 0.1%. In accordance with the standard (GOST 13264-67), whole milk must contain at least 3.2% fat.

Determination in skim milk. It is produced in the same way as in whole milk, using the sulfuric acid method but in special butyrometers with a scale divided into tenths and hundredths of a percent. All components included in the analysis of whole milk are poured into such butyrometers in double quantities: 20 ml of sulfuric acid, 21.54 ml of skim milk and 2 ml of isoamyl alcohol. The exposure in a water bath before and after centrifugation is the same, but threefold centrifugation is used.

DETERMINATION OF ACIDITY OF MILK

Freshly milked milk has an amphoteric reaction. An increase in the acidity of milk is caused by the breakdown of milk sugar into lactic acid, caused by the development of lactic acid and other bacteria. The longer milk is stored unrefrigerated, the more lactic acid accumulates in it.

Freshly milked milk from a healthy cow has 16-18° acidity. Increased acidity can be observed in the milk of cows grazing in summer in areas with acidic grains or in wet meadows. The acidity of colostrum reaches 50° Turner, and at the end of lactation it drops to 12-14°. With mastitis, the acidity of milk decreases to 7-15° Turner. Cow's milk procured for state and cooperative purchases on collective farms, state farms and other farms should not have an acidity higher than 20°. The acidity of first-grade milk is usually 16-18°, second-grade milk is 19-20°, and non-high-grade milk is 21°.

Determination of titratable acidity of milk. Titratable acidity is indicated in degrees of titration - Turner T°. The degree of acidity is the number of ml of decinormal alkali solution used to neutralize 100 ml of milk.

Research method: 10 ml of the milk under study, 20 ml of distilled water and 3 drops of 1% phenolphthalein are poured into a conical flask and titrated with a 0.1 alkali solution until a faint pink color appears, which does not disappear within one minute. The number of milliliters of alkali used for titration, multiplied by 10, shows the degree of acidity of the milk being tested. During mass acceptance of milk in markets, the maximum acidity is determined.

Extreme acidity. Maximum acidity is the degree of acidity of milk, above which milk is not allowed for sale. When selling milk on markets, the maximum acidity should not be higher than 20" and lower than 16°.

Research methodology; 10 ml of 0.01 N alkali solution is poured into a row of test tubes placed in a stand, which is prepared as follows: 100 ml of 0.1 N alkali solution and 10 ml of 1% phenolphthalein solution are measured into a liter flask, distilled water is added up to a volume of 1 liter. 5 ml of milk is poured into a test tube with 10 ml of indicator. If the acidity of the milk is below 20°, then an excess of alkali remains in the test tube and the pink color remains; if the acidity is higher than the limit, then there is not enough alkali to centralize it and the liquid in the test tube becomes discolored. An increase in the acidity of milk can occur when cows are fed spoiled silage or pulp containing oxalic acid, as well as when cows are fed concentrated feed in excess of norms. An increase in acidity, as well as milk density, is observed in the initial stage of cows' disease with mastitis.

DETERMINING THE PURITY OF MILK

One of the main indicators characterizing the quality of milk is the degree of its purity. Filtering dirty milk. no matter how carefully it is carried out, it does not improve its quality, but on the contrary, it deteriorates faster, because dirt inactivates the bactericidal and bacteriostatic substances contained in it (lysozyme, lactenins, bacterilysins, etc.).

Determination of the degree of purity of milk. The purity of milk is determined using the Record device. 250 ml of milk is passed through the device, the filter is dried and compared with special standards, on the basis of which I establish the milk purity group.

Based on the degree of contamination, milk is divided into 3 groups. The first group includes milk, during filtration of which the sediment is almost invisible. The second group includes milk that has traces of contamination on the filter (in the form of small dots). Milk from the third group clearly shows contamination. A mechanical suspension in the form of larger dots is noticeable on the filter; the color of the filter is gray.

According to GOST 13264-67, first-grade milk must have purity group I, second-grade milk must have group II purity, and non-grade milk must have at least group III purity.

Determining the presence of soda in milk. Sometimes, in order to protect milk from curdling due to high acidity, soda is added to it. However, soda does not increase its resistance, but on the contrary, favorable conditions are created for the development of putrefactive microflora. To determine soda in milk, indicators are used: rosolic acid, bromothymol blau. phenolrot.

Research method: 1 ml of the milk being tested is placed in a test tube and the same amount of 0.2% roseolic acid solution is added. Milk that does not have an admixture of soda with roseolic acid acquires an orange color, and milk containing soda becomes raspberry-red.

CHECKING THE QUALITY OF MILK PASTEURIZATION

On farms that are vulnerable to infectious diseases in cattle, milk is pasteurized. In this regard, there is a need to control the quality of pasteurization. To check the quality of pasteurization, a peroxidase test is used on farms, and a phosphatase test is used at dairy industry enterprises.

Reaction to peroxidase: if you add a few drops of a solution of potassium iodine starch and one drop of a solution of hydrogen peroxide to raw milk, the following reaction will occur: peroxidase + H2O2 + 2KOH + starch == 2KOH + J2 + starch, i.e. a blue color appears. In milk heated to 80-85°, a color change will not occur, since peroxidase is destroyed when heated.

Research method: To 3-5 ml of the milk being tested in a test tube, add 5 drops of potassium iodide starch (3 g of potassium iodide and 3 g of starch per 100 ml of water) and 5 drops of a 1% solution of hydrogen peroxide. The appearance of an intense blue color indicates the presence of peroxidase in milk. Therefore, this milk has not been pasteurized. The appearance of a pale blue color indicates partial destruction of the enzyme under the influence of milk at a temperature of 65-70°, i.e. the milk is not pasteurized enough.

Phosphatase reaction. The enzyme phosphatase is less resistant to heat compared to peroxidase. Consequently, this reaction can establish the correctness of compliance with the low pasteurization regime, which is used in dairies.

Research methodology; 2 ml of the test milk and 1 ml of sodium phonolphthalein phosphate solution are poured into the test tube, closed with a stopper and after thorough mixing, the test tube is placed in a water bath at 1 40-45 °. The reaction is read after 10 minutes. In a test tube with properly pasteurized milk, no changes are observed. If the pasteurization regime is violated and the phosphatase remains active, the contents of the test tube take on a bright pink color.

DETERMINING THE CLASS OF MILK

Milk classification is a chemical method for determining the degree of microflora contamination of milk. It is established by a reductase test.

When determining the class of milk, we tentatively establish that the microflora, multiplying in milk, releases the products of its vital activity - reductase, which has the ability to discolor some paints, in particular methylene blue or change the color of resazurin. Consequently, the more microflora the milk contains, the more reductase is released and the faster the methylene blue discolors or the color of resazurin changes.

The reductase test with methylene blue is carried out as follows; 1 ml of methylene blue solution (5 ml of a saturated solution and 195 ml of distilled water) is poured into a test tube and 20 ml of the milk being tested is added. If there are no test tubes big size, you can use regular ones, but the amount of milk and reagent is halved. After stirring, place in a water bath at 38-40°C and observe the discoloration of the contents of the test tube every 15-20 minutes.

Based on the time of onset of discoloration, the good quality of the milk is determined, as can be seen from the table data:

Good quality of milk and class

The disadvantage of the reductase test with methylene blue is that it poorly detects milk contamination in winter. If during milking (in unsanitary conditions) bacteria get into the milk and it is immediately cooled to 4°C or lower, then the biochemical activity of microorganisms is delayed. In addition, milk for streptococcal mastitis can be of the first class according to the reductase test with megillenope blue.

Reductase test with resazurin. Due to the fact that the methylene blue test has disadvantages, a resazurin test is used.

Method: 10 ml of test milk is poured into a test tube and 1 ml of 0.05% resazurin solution is added. The test tubes are closed with sterile stoppers, placed in a water bath at 42-43° and the time is noted. Observation is carried out after 10 minutes and 1 hour. Resazurin is reduced by reductase to refurin (pink).

This test makes it possible, comparatively faster than with methylene blue, to obtain results for assessing milk according to the degree of bacterial contamination. It is very important that this sample is the milk of cows with mastitis.

To increase the effectiveness of the resazurium test, I.S. Zagaevsky proposed adding 0.5% formaldehyde to a 0.05% solution of resazurin; as a result, the photosensitivity of the indicator in milk decreases and the accuracy of the analyzes increases.

The results of this test are taken into account according to the following indicators

first class - blue-blue color in vitro,

second class - blue-violet,

third class - pink.

It should be noted that the reductase test with resazurin. Compared to methylene blue, it speeds up analysis by more than five times. Constant monitoring of the reaction progress is not required. Reveals the reductase of all microorganisms that contaminate milk and is more demonstrative when reading the reaction to the quality of milk.

MICROBIOLOGICAL ANALYSIS OF MILK

Microbiological examination of milk is carried out and following cases: 1) when there is a suspicion that it may pose a danger to human health, 2) in order to monitor the sanitary and hygienic regime of milking and primary processing of storage and transportation, 3) in case of suspected contamination with microorganisms, in the presence of which the milk cannot be processed in dairy products, 4) to establish the microflora that caused inflammation of the mammary gland and its antibiotic resistance.

In most cases, microbiological examination of milk is limited to determining the total number of bacteria and fermentation titer. If milk is suspected of being contaminated with pathogenic microorganisms, special studies are carried out depending on the type of suspected pathogen. Milk must be examined immediately after taking the sample, otherwise it should be cooled to 4-6° (not higher). Labels indicating the sample number, the number and size of the product batch, the day and hour of sampling are affixed to the dishes with milk samples for research. The label must contain the signature of the person who took the sample, indicating his position. If milk samples are sent to a laboratory located outside the enterprise (collective farm, state farm), they are sealed and sealed.

Cup method. To determine the total number of microbes in milk, the test material is added to a Petri dish and filled with nutrient medium in an amount of 12-15 ml. During the study, it is necessary to pre-dilute the milk in sterile water. Dilutions are made in such a way that the last of them contains a dozen cells in 1 ml. For inoculation onto Petri dishes, the last three dilutions are usually used. The seeded cups are placed in a thermostat at a temperature of 37°. Counting of grown colonies is carried out after 24 and 48 hours. The number of colonies in each cup is multiplied by the degree of dilution of the milk. From each milk sample, colonies should be counted on three plates and the average numbers taken. The sum of colonies in all cups is divided by the number of cups and thus the microbial contamination rate of 1 ml of milk is determined.

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