How to identify quality meat, evaluate freshness and store properly. Analysis of the quality of meat and meat products

Requirements for the quality of chilled meat

Chilled meat is called, the temperature in the thickness of the muscle tissue of which at a depth of 6 cm is from 0 to +4 o C.

• Pale pink to pale red color;
• Dry, superficial crust of drying;
• The consistency is elastic, the dimple from pressure quickly disappears;
• The smell is typical of the type of meat, without signs of spoilage. The smell is determined on the surface, in the place of the cervical incision, in the thickness of the muscles near the bones, on a fresh incision;
• The surface of a fresh cut should be slightly moist, but not sticky, of a certain uniform color for each type of meat;
• Meat juice should be clear;
• Beef and lamb fat is solid. Pork fat - soft, elastic. The smell of fat - without salting and rancidity.

Requirements for the quality of frozen meat

Ice cream is called meat, the temperature in the thickness of the muscle tissue of which at a depth of 6 cm is below minus 8 ° C

• The color is brighter than chilled meat;
• The surface of the cut is pinkish-gray, due to the presence of ice crystals, a spot of bright red color appears at the point of touch with a finger or a warm knife;
• Solid consistency;
• The color of beef fat is from white to light yellow, lamb and pork fat is white;
• Frozen meat has no smell. When thawed, there is an odor characteristic of this species, but without the aroma of ripe meat. To determine the smell of frozen meat, it is necessary to insert the blade of a heated knife into the depths of the muscles, towards the bones.

Meat according to freshness is divided into: fresh, dubious freshness, stale.

Fresh meat

If the meat does not fall into the category of fresh according to its characteristics, it is classified as questionable freshness or stale (depending on the degree of changes that have occurred).

Meat of dubious freshness

The smell is sour on the surface, specific in the thickness;

Appearance: the surface is moistened in places, slightly sticky, the muscles are moist on the cut;

Color on the surface and at a depth of 2-3mm, gray or dark;

Consistency - when pressed, the fossa is leveled slowly, in 1-2 minutes;

Adipose tissue is softer in consistency than in fresh meat, slightly sticky, has a slight smell of salting, a specific color;

Meat of dubious freshness is not allowed for sale.

The meat is not fresh.

The smell on the surface and in the thickness of the meat is sour, musty or putrid;

Appearance: the surface is dried up, covered with gray mucus, on the cut the muscles are moist, sticky;

The color on the surface and at a depth of 2-3 mm is gray, greenish, dark, in the thickness of the muscles with foci of gray or dark green;

Consistency - flabby, the fossa from pressure is not aligned;

Adipose tissue is gray-matte, ointment-like consistency, sticky, the smell is rancid, putrid or salting;

Meat that is not fresh is not allowed for sale.

Changes in chilled meat during storage

During storage, meat can undergo various changes. Some of them occur due to physicochemical factors, others are due to the decomposition of meat due to the development of microflora. The speed of the onset of changes, their nature and depth depend on a number of factors, namely, the condition of the animals before slaughter, the sanitary and hygienic conditions for their processing and storage of meat, and the composition of the microflora.

TANN MEAT. This is a type of meat spoilage that appears on the first day after the slaughter of the animal. The factors contributing to this deterioration are as follows: high temperature in the room where the meat is stored, lack of ventilation, high humidity, dense suspension of carcasses and their significant moisture. All this does not ensure rapid heat removal from the steam carcass or half carcass. Especially often sunburn appears in large and fat carcasses (fat pigs), which cool more slowly, since fat is a poor conductor of heat. Especially often sunburn occurs in fresh meat when transporting it to closed container. Deep layers of meat long time are not chilled. Insufficient aeration reduces oxidative processes in meat, accelerating the anaerobic breakdown of carbohydrates with the accumulation of acidic products of glycolysis, hydrogen sulfide, butyric acid and other unpleasant odors. Myoglobin undergoes significant changes, with the formation of pigments that change the color of the meat. In this case, there is a sharp increase in the concentration of hydrogen ions. When tanning, the pH decreases to 5.1-5.2, its organoleptic parameters change. Poultry carcasses are painted in a copper-bronze color, the smell of meat is suffocatingly sour with an admixture of hydrogen sulfide, the consistency of muscle tissue is flabby. There is no microflora in meat. It is generally accepted that the process in meat proceeds due to tissue enzymes. If deep autolytic changes have not passed (the initial stage of sunburn), then you can try to eliminate the defect. To do this, the meat is cut into small pieces and ventilate in a well-ventilated area.

SANITARY ASSESSMENT . If bad smell disappears and the normal color is restored, the meat is used for industrial processing. If this does not happen, then the meat is sent for technical disposal. In culinary production, the use of such meat is prohibited.

MEAT COLOR CHANGE . At long-term storage meat, even at a low positive temperature, its darkening is noted. The process begins in the incision area and extends to the humeroscapular region. These processes can proceed due to physicochemical factors, due to the breakdown of hemoglobin. Sometimes the meat turns bright scarlet. This is due to increased activity of enzymes that lead to the oxidation of hemoglobin and myoglobin.

SANITARY ASSESSMENT . In the presence of these changes, the meat is used for food purposes in the network Catering.

GLOW MEAT.(phosphorescence) This is due to the development of photobacteria on meat, semi-finished products, finished meat products. The most common are Photobacterium fischeri, Ph. pontikum, Ph. cyanophosphoreszens and other species. They are obligate aerobes. In the presence of colonies, the meat in the dark emits a bluish, greenish-yellow or bluish light. The glow can be point, focal or continuous. Photobacteria get on meat in storage chambers. Their development is facilitated by increased humidity, storage temperature above 5 ° C. The glow is most often observed on the joints, intervertebral cartilage. No toxic products are formed in the carcasses. It should be noted that putrefactive microflora is an antagonist of photobacteria. Therefore, when putrefactive microflora appears, the glow of meat stops.

SANITARY ASSESSMENT. The meat is washed with a weak solution acetic acid, dried and released for free sale.

SLICKING MEAT. This spoilage process is associated with the development of mucus-forming microorganisms. These include various types of lactic acid bacteria, yeast. Sliming is facilitated by storage of carcasses at high temperatures, high humidity, suspension of carcasses without gaps between them. The microflora that causes mucus does not penetrate into the depth of the meat, so the mucus is only on the surface of the carcass. The meat is sticky, grayish in color, with a sour smell from the surface. In the deep layers, the meat has no deviations from the norm.

SANITARY ASSESSMENT. In the presence of mucus, cleaning is carried out by cutting off a thin surface layer. Carcasses after sanitization are sent for industrial processing. In culinary production, the use of such meat is prohibited.

MOLDING MEAT. Contamination of meat with mold spores occurs from the walls of storage chambers. Molds are aerobes and grow on the surface of meat in an acidic environment, low humidity and temperature. Some types of mold stop growing only at a temperature of minus 12C. Mold takes a relatively long time to develop.

Most often, 4 types of molds are found on meat:

1. Round, white, velvety colonies of mucor and tamnidium, grow on the surface and are easily removed.

2. Colonies are dark gray, brown or greenish-bluish - penicillum, germinate to a depth of 4 mm.

3. Green or black mold coloniesAspergillus glaucus, asp. Nigeria.

4.Large black colonies-spotsCladosporium herbarumpenetrating into the thickness of the meat up to 1 cm.

Many of them form mycotoxins that are dangerous to humans and animals. They have a very strong toxic effectCladosporium herbarum.

With the growth of molds, the pH of the meat shifts to the neutral side, fat breaks down, which leads not only to a change in the presentation, but also a musty smell.

SANITARY ASSESSMENT. It is carried out depending on the type of mold. If the meat is affected only by white mold growing on the surface, then it is wiped with a solution of acetic acid or brine and sent for sale. If the meat is damaged by green or black mold, the muscle tissue is stripped to a depth of 15 cm, after which a cooking test is carried out. If there is no foreign smell, then the carcass is sent for industrial processing, in the presence of a musty smell, the carcass goes to technical disposal.

ROTTEN MEAT. This is the process of decomposition of protein and other meat substances under the influence of putrefactive and other microflora enzymes, with pronounced proteolytic and peptolytic functions. When meat rots, aerobic and anaerobic processes partially occur simultaneously. Of the aerobes putrefactive bacteria are: Bak. proteus, Bak. mycoides, Bac.subtilis, Bac. Mesentericus From anaerobes leading role already in the initial stage of decay I play: Cl. Putrificus, Cl. Perfringes, Cl. Putrifaciens, Cl. sporogenes.

Putrefactive microflora can penetrate into the meat in an exogenous and endogenous way. The meat of tired and sick animals is not resistant to the action of putrefactive microflora, since its pH is 6.3 and higher. In meat obtained from healthy, rested animals, the development of putrefactive microflora is prevented by an acidic environment (pH 5.8-6.2), which occurs during normal maturation. However, meat can also rot in healthy animals if surface contamination occurs. The microflora penetrates into the depth of the muscle tissue through the connective tissue fascia, where the pH is about 7.0. This explains the appearance of signs of damage in the bones earlier than in the muscles.

One of the initial products of putrefaction are peptones, which cause poisoning when administered parenterally. During the hydrolysis of peptones, free amino acids are formed, which are further subjected to deamination, oxidative or reductive decarboxylation. During deamination, free fatty acids are formed, and during decarboxylation, various amines are formed - ethylenediamine, cadaverine, putrescine, skatole, indole, histamine. From the amino acids - cystine, cysteine, hydrogen sulfide, ammonia and mercaptans are formed. From choline, when putrefied, a poisonous compound, neurin, can be formed.

Meat in the initial stage of decay is more dangerous for humans. At the stage of deep decomposition, already final, less toxic or non-toxic decomposition products are formed.

When rotting, the structure of meat changes, the connection between muscle fibers weakens. On different stages putrefactive meat has various smells - musty, sour, rancid, putrid.

SANITARY ASSESSMENT. Meat with signs of decay is sent for technical disposal.

Package

Products must be packaged in such a way as to provide maximum protection.

The materials used in packaging must be clean and of a quality that will not damage the product.

There must be nothing foreign inside the packages.

When using a polyethylene film for chilled products, tight packaging is not allowed, especially in warm weather, an air gap is required between the product and the packaging so that the processes of meat spoilage are not accelerated and it does not “fade” when a musty smell is felt when opening a tightly fitting film .

If the meat is delivered in carcasses, half and quarter carcasses, then it should be placed in the vehicle and in the storage rooms on hangers, and not on pallets in bulk.

Marking

Each package must bear the following information, written in indelible ink and legible:

• packer: name, address or official trademark;
• product type: name, class, variety (optional);
• origin: country, region, locality name;
• date of packaging, expiration date and storage conditions of the product;
• if the meat is delivered in carcasses, half and quarter carcasses, then the stamp on the carcass must be legible. At the same time, on the carcasses of large animals, the brand should be on each thigh and shoulder blade, on the carcasses of small animals - on one thigh and one shoulder blade diagonally (* right thigh - left shoulder blade). On the carcasses of all types of animals, except for beef and pork, there must be a stamp indicating the species. Such a stamp is placed next to the hallmark.

Product Requirements

quality requirements

Carcasses, half-carcasses and quarters must enter the market without contamination, fringes, bruises, bruises, blood clots and residues internal organs. The exception is carcasses of veal and lamb, which leave the kidneys and perirenal fat.

On beef carcasses, stripping and breakdowns are allowed subcutaneous fat, not exceeding 15% of the surface area, veal and lamb - not more than 10%. For pork, trimmings of no more than 10% are allowed, and breakdowns of subcutaneous fat, not exceeding 15% of the surface area.

Frozen meat must also be free of snow and ice.

Storage temperature

Food products during their manufacture and circulation (production, storage, transportation and circulation) must be stored under conditions that ensure the preservation of their quality and safety throughout the entire shelf life.

Transportation should be carried out using refrigerated or isothermal transport, subject to the required temperatures: chilled products - minus 1 +4 ° C, frozen products - not higher than -18 ° C, unless otherwise indicated on the product labeling.

When storing meat, the temperature conditions should be the same as during transportation.

	Shelf life	(in months)	at temp.
Beef and lamb
Second " "
No skin..
Chickens, chickens, turkeys, game.
Geese, ducks.
By-products…….	No more than 4-6 months

Re-freezing of thawed meat is not allowed.

For vacuum packaging special packaging materials. Ordinary polyethylene is gas permeable and not suitable for vacuum packaging. The most common two-layer films are polyamide - polyethylene and lavsan - polyethylene.

In a gas environment, the shelf life of products is doubled compared to vacuum packaging.

Farm animals intended for slaughter are collectively referred to as slaughter animals. Cattle (including buffaloes, yaks), sheep, goats, pigs, horses, deer, camels, as well as poultry - chickens, geese, ducks, turkeys, guinea fowls are supplied to meat processing enterprises. Meat is obtained from the slaughter of livestock.

Meat- a carcass or part of a carcass obtained from the slaughter of livestock, which is a combination of muscle, connective (loose and dense), adipose and bone (or without it) tissues.

The main indicator characterizing the meat quality of livestock and poultry is their fatness. Cattle and poultry of unequal fatness differ in the ratio of muscle, fat, bone and connective tissues in carcasses. In well-fed animals, compared to under-fed animals, the proportion of adipose tissue in the carcasses increases, the proportion of muscle decreases slightly, and the proportion of bones, cartilage and connective tissue decreases significantly. With a change in the ratio of tissues, chemical composition meat (protein, fat, water content), which determines its nutritional value, calories and taste qualities.

With an increase in the fatness of animals, an increase killer exit (carcass weight as a percentage of live weight), and hence the total meat yield. At the same time, the meatiness of the carcass also increases due to a decrease in the specific gravity of the bones. However, the increase in the yield of edible parts of the carcass when fattening animals to high fatness conditions in most cases occurs due to the increase in adipose tissue and, to a lesser extent, muscle tissue.

With a high fat content in carcasses, the technological value of meat as a raw material for industrial processing is reduced. In addition, with excessive fat content of meat, its nutritional and culinary qualities, digestibility decreases.

The fatness of livestock and poultry, their meat qualities depend on age and weight, sex, breed and direction of productivity.

When evaluating the meat qualities of young animals, the main indicator associated with meat productivity and quality of meat, is their live weight. Intensively reared and fattened to high weight standards young animals

Cattle and poultry for slaughter, meat in carcasses, half carcasses and quarters

differs in high rates of the general output of meat and the increased meatiness at the expense of well developed muscular tissue. Young meat has an optimal ratio of protein and fat, has high nutritional and dietary properties, is distinguished by tenderness, juiciness and high palatability. Juvenile fat is white.

With age, the fatness and weight of animals with normal feeding increase. The amount of fat in the composition of meat increases. The meat of older animals contains more connective tissue. Muscle tissue has low taste, becomes drier and tougher, loses tenderness and juiciness; connective tissue is difficult to boil; adipose tissue yellow color. The meat of bulls is tougher, does not have marbling, and has an unpleasant garlic smell, which can disappear when the meat is stored in a frozen state or when aged in salting.

Slaughter cattle and poultry must comply with the requirements of veterinary legislation, the rules of veterinary inspection of slaughter animals.

The consumer value of meat, regardless of the type of animal, is characterized by its taste and nutritional qualities, the yield of edible parts of carcasses and carcasses, the ratio of bones and pulp in them, as well as meat and fat, the yield of various types of meat (cuts) from carcasses.

The nutritional value, technological properties, commercial quality of meat depend on the type of animal, its breed, sex, age, fatness, pre-slaughter content, origin (anatomical part of the carcass) and other factors.

When assessing the quality of meat in carcasses, half-carcasses, quarters, in addition to the morphological composition of the carcass, organoleptic, sanitary-hygienic, and technological indicators are determined. Organoleptically determined appearance meat, color, marbling, structure, smell, consistency.

The color of the meat is judged on its presentation and, to some extent, on the chemical transformations in it.

Taste and smell depend on the species, age, sex of animals, feed ration and other factors.

The consistency is characterized by tenderness, softness, juiciness. These indicators depend on the water-holding capacity of the meat. The larger it is, the less the meat will lose water during cooking and, therefore, it will be juicier. finished product. Tender meat tends to be juicier.

Sanitary and hygienic indicators characterize the safety of the product for humans (see Chapter 5). The technological properties of meat are judged by water-binding capacity, consistency, pH, connective tissue content, fat content and condition.

The indicators of the commercial quality of meat include characteristics that ensure the convenience of selling the product, as well as signs and properties by which the consumer makes a primary judgment about its quality, namely: appearance, color, smell, mass of the product, packaging. Meat must comply with the requirements of the rules of veterinary and sanitary examination, sanitary and epidemiological rules and regulations and be produced in accordance with the veterinary and sanitary rules for meat products enterprises.

Influence of the main intravital factors on the quality of carcasses and meat.

One of the vital factors affecting the quality of carcasses and meat is animal age. Significant changes occur in the body of animals with age, which subsequently have a significant impact on the quantity and quality of meat products. The relative share of bone tissue decreases, the absolute and relative content of meat, subcutaneous, intermuscular and intramuscular fat increases.

The mass of nutritionally valuable muscles increases most intensively during the first year of the animal's life, and then the rate of their growth slows down. If the mass of bone tissue in the carcasses of newborn calves is 34 - 36%, then at the age of 18 - 20 months - 17 - 19%. The meat of 6-month-old bulls contains 20-21% protein, 4-5% fat, and at the age of 18-20 months, respectively, 18-19 and 10-14%.

The meat of young animals is characterized by tender muscle tissue, a higher glycogen content, and a low fat content. Connective tissue breaks down easily. The meat of adult animals is characterized by a large deposition of fat under the skin, between the muscles, in the abdominal cavity, denser muscles and connective tissue, the number of elastic fibers increases, collagen fractions change, it is more for a long time undergoes cooking.

Animal gender. Sex differences in meat quality at an early age are less significant compared to adult animals. The meat of females is more fine-fibered, tender, juicy, tasty, fragrant, with a high fat content and pronounced marbling. Castrates most often occupy an intermediate position in these indicators. For example, the fat content in the average sample of black-and-white cattle meat at the age of 16-20 months is 10-14%, castrates - 16-20% and in the meat of heifers - 20-26%, intramuscular fat, respectively, 1.5 - 1, 9%, 3.0 - 4.0 and 3.2 - 4.6%.

The meat of heifers contains less defective proteins, and their connective tissue is much more tender than in the meat of bulls. In the muscles of 16-20-month-old bulls, defective proteins contain 20-21%, castrates - 15-16%, heifers - 5.4-5.8%, and moisture retention, respectively, 63-70%, 58-62 and 55-60% . The meat of gobies does not ripen and store well, but it is a good raw material for sausage production.

In terms of quality of carcasses, pigs are superior to hogs. When slaughtering animals with the same live weight, as a rule, the yield of meat in gilts is higher, and fat is lower than that of hogs. The chemical composition of the meat of pigs and hogs is almost the same.

animal breed. Many indicators of the quality of carcasses and meat depend on the breed of animals. From animals of most beef cattle breeds, more tender, juicy and tasty meat is obtained. They have well-developed muscle tissue, especially in parts of the body from which the most valuable meat is obtained - in the hip, lumbar and spinal parts.

Meat breeds also differ significantly from each other in terms of fat content in meat and intramuscular fat. It is especially deposited in the meat and muscles of British breeds (Hereford, Aberdeen Angus and Shorthorn) and much less in French breeds (Charolais, Light Aquitaine and Limousin). Meat from dairy cattle is of lower quality, has more connective tissue and less intramuscular fat.

Animal fatness. With an increase in fatness, the morphological composition of carcasses and the chemical composition of meat change. In carcasses, the relative content of bones decreases, the amount of muscle and adipose tissue increases. The meat of well-fed animals is characterized by more high content fat, reduced amount of water, collagen and elastin. It has a more delicate texture. The meat of well-fed animals has a less intense color and is better stored. In very fatty meat, the protein content is reduced and it is less digestible. In the meat of poorly fed animals, the content of connective tissue increases and it is more rigid. The meat of fatty fat pigs contains more sarcoplasmic proteins, and the carcasses of lean pigs contain more myofibrillar proteins.

Feeding conditions- one of the most important factors determining the quality of meat. The amount of feed, composition and nutritional value of the diet can regulate the morphological composition of carcasses and the chemical composition of meat. With an increase in the level of protein in the diet, the deposition of fat in meat slows down, and an increase in metabolic energy in the diet, on the contrary, stimulates the process of fat formation.

These techniques are widely used in the rearing of young birds. At the end of fattening, for broilers and turkeys, an increased level of energy nutrition is used, which allows to increase the yield of carcasses of the 1st category, and for ducks, on the contrary, they reduce the level of nutrition, since they have increased fat formation. When young birds are fed feed mixtures with a high content of corn, the proportion of high-grade fatty acids, including linoleic, linolenic and arachidonic.

All feeds are divided into 3 groups according to their effect on the quality of pork:

- feeds that improve the quality of pork: barley, wheat, rye, broad beans, peas, carrots, sugar, semi-sugar and fodder beets, potatoes, clover grass, alfalfa, vetch and pea-oat mixtures, reverse, whey. When these feeds are included in the diet, the quality of pork increases;

- feed, when fed, soft lard and loose, tasteless pork are obtained. These include: corn, oats, bran, beet molasses, potato pulp. Pork High Quality obtained in the event that the diet will consist of no more than 50% nutritionally from these feeds;

- feed, sharply deteriorating the quality of fat and meat due to the content of vegetable fats or a specific smell. These include cakes, fish, fishmeal, soybeans. These feeds can make up no more than 25% in nutritional value in the diet of fatteners, and one and a half months before slaughter, it is necessary to completely stop giving feed that worsens the quality of pork.

With the widespread use of various chemicals in crop production, they can accumulate in animal tissues from feed and pose a certain danger to humans. The source of accumulation of salts of heavy metals can be feed and water.

Meat defects P SE And DFD .

Ante-mortem content at cattle bases of meat processing enterprises significantly affect the quantity and quality of meat, especially its technological properties. The high content of glycogen in the body of animals before slaughter contributes to the formation of lactic acid, low pH of meat, which is associated with water-holding capacity, tenderness, juiciness, losses during heat treatment, safety, bacterial contamination, color and other indicators of meat quality.

The breakdown of glycogen is called glycolysis. The intensity of glycolysis depends on many conditions, but mainly on the amount of glycogen in the muscles and the activity of tissue enzymes. Animal muscles contain 0.3 - 0.9% glycogen. It is more contained in the muscles of well-fed and tireless animals grown in grazing conditions, less - in the muscles of malnourished, hungry, excited and tired animals grown in complexes or tethered conditions.

With fatigue, overheating, hypothermia, prolonged pre-slaughter exposure and in sick animals, the amount of glycogen and the activity of tissue enzymes decrease. Therefore, lactic and other acids accumulate in smaller quantities and the quality of the meat deteriorates. A slight accumulation of acids in the muscles creates favorable conditions for the development of microflora and a reduction in the shelf life of meat.

Before slaughter, with intense muscle load, stress, excitement, especially in bulls, glycogen undergoes glycolytic breakdown. Therefore, after slaughter, a small amount of glycogen remains in the muscles, little lactic acid is formed, and the pH value is very high.

As you know, during the life of the body, the conversion of glycogen is carried out in the following sequence: glycogen + oxygen = energy + CO 2 + H 2 ABOUT . After the slaughter of the animal with the cessation of breathing and, as a result, the cessation of oxygen access to the muscles, the reaction proceeds under anaerobic conditions in the following form: glycogen = energy + lactic acid . If the rate of post-slaughter glycogen conversion is normal, then its breakdown and conversion into lactic acid mainly occurs within 12 to 24 hours, and the meat becomes elastic and has a light pink color. It acquires the ability to long-term storage.

If there is little glycogen in the body of animals, then after slaughter, the development of glycolysis in carcasses is inhibited, and sometimes it is almost or completely absent. Meat maintains a high pH value. In this case, the pH value of the meat, measured during the first hour after slaughter, practically does not differ from the pH after 24 hours. The final pH value of the meat remains at 6.3 and above. Such meat becomes dark, dense, dry, a favorable environment is created for the development of undesirable microflora.

Excessively high acidity of meat entails partial denaturation of proteins, which adversely affects its water-holding capacity and color. It becomes pale, soft, quickly loses juice and is not able to absorb water. When pigs are stressed after slaughter, there is a high rate of glycolysis at a relatively high temperature in carcasses (from 42 to 45 0 C), which leads to significant chemical changes and a sharp decrease in pH. During the first hour after slaughter, the pH may drop to 5.5 - 5.9.

Increased acidity in still functioning cells causes protein breakdown or denaturation, leading to low water-holding capacity and pale pigmentation. Such meat is pale, soft, not tender enough in texture, poorly stored, with reduced technological properties and increased losses during cooking and processing.

Violation of glycolysis entails the formation of meat defects, which are indicated symbols PSE (pale, soft, watery) and DFD (dark, dense, dry).

PSE and DFD meat malformations result from an abnormal rate of post-mortem glycolysis in the muscle. If meat PSE is formed as a result of excess lactic acid content, then DFD is a consequence of its insufficient amount. With DFD due to reduced content lactic acid as a preservative, the meat quickly darkens, becomes hard, dry, prone to accelerated spoilage under the influence of microflora and is poorly stored. The DFD defect most often covers only individual parts of the carcass. For example, the pH value of the longissimus dorsi muscle of bulls was 6.6, and the triceps muscle of the shoulder was 5.8.

With the intensification of pig breeding in the meat direction, meat defects are more common. German experts believe that eating meat with such defects causes various diseases of the gastrointestinal tract in humans.

PSE meat defect most often occurs in pigs, DFD defect - in bulls grown in industrial complexes. The main reasons for their appearance are the intensive growth of animals, the same type of feeding, limited movement and increased susceptibility to stress.

The carcasses of industrial fattening bulls can be divided into 3 groups according to the pH value measured 45-60 minutes after slaughter: meat with a defect - pH up to 6.2, normal meat - 6.3 - 6.6 and meat with a defect - pH 6 ,7 and more. After daily storage - meat with a defect of 5.4 - 5.6, normal meat - 5.7 - 6.2 and meat with a defect - pH 6.3 and above.

Thus , ante-mortem losses associated with the quality of meat, no less significant than quantitative ones. Therefore, in the muscles of animals, especially during transportation, pre-slaughter and during slaughter, it is necessary to maintain the maximum amount glycogen, which will contribute to the intensive processes in the meat with the formation of a significant amount of lactic acid.

Influence of primary processing of animals on marketable condition, the quality of carcasses and meat.

When driving animals to the place of slaughter, additional stresses arise, a significant number of injuries are noted and the quality of meat decreases. In addition, areas of carcasses with bruises and wounds are removed, which leads to loss of meat and deterioration of the presentation of carcasses. To adjust animals, it is necessary to use means that do not injure their skin and subcutaneous tissue.

Animal Stunning has significant drawbacks, since at the moment the current is connected, a sharp contraction of muscle tissue occurs, which leads to rupture of tendons, ligaments, fractures of the spine and limbs, rupture of small vessels and petechial hemorrhage. Because of this, the ability of meat to store is reduced. An overdose of current leads to severe disturbances in cardiac activity and often ends in the death of the animal. With incomplete stunning, pain persists and the animals are not completely immobilized.

Complete and high-quality exsanguination allows you to get a marketable appearance of carcasses and increases the shelf life. In poorly bled carcasses, the blood remaining in the blood vessels is a good medium for the development of microorganisms. Animal fatigue during transportation, stress, physical activity before slaughter and illness increase blood flow to the muscles, which makes it difficult to bleed the carcasses. In a vertical position, carcasses are bled 35-40% better than in a horizontal position.

It is necessary to perform skinning in such a way as to prevent the breakdown of meat and fat from carcasses, cuts into which putrefactive microorganisms penetrate and cause meat spoilage, and also worsen the marketable appearance of the carcass. With a belated (more than 45 minutes after exsanguination of animals) extraction of internal organs, the microflora of the gastrointestinal tract begins to penetrate the meat and leads to spoilage.

The presentation of the carcasses is given during its stripping. But when abscesses, traumatic injuries, remaining pieces of internal organs and skin, bruises on the surface of the half carcass are removed, the quality of the meat and its stability during storage decrease. Carcasses are washed only from the inside and only if they are dirty. In case of surface contamination, only the contaminated areas are washed with subsequent removal of moisture. When the outer surface is moistened, the meat is poorly stored.

Effect of heat treatment on meat quality.

Character heat treatment of meat has a great influence on the degree of digestibility of its nutrients by the human body. By using one method or another cooking meat, you can increase or decrease the degree of its digestibility. During the culinary processing of products, the maximum preservation of the full-fledged proteins, fats, vitamins, and mineral salts contained in them should be ensured. Under the influence of various physical and chemical factors, a number of initial properties are lost, primarily the solubility of proteins, since denaturation of protein molecules occurs. Protein denaturation occurs in the presence of water.

At a temperature of 60 - 100 0 С, proteins lose their ability to dissolve in water, salt solutions and organic solvents, their ability to swell decreases. The change in proteins during thermal denaturation is the greater, the higher the temperature and duration of heating, and the protein in an aqueous solution denatures faster than in the dried state. Changes in meat proteins during heat treatment affect the quality of the finished product.

During normal cooking in meat, the content of lysine, methionine and tryptophan . When meat products are sterilized, their digestibility decreases somewhat, stiffness increases and the biological value of proteins decreases. Prolonged autoclaving leads to significant losses of amino acids. Losses of vitamins B 1 and B 2 during cooking reach 15 - 40%, during frying - 40 - 50% and during stewing - 30 - 60%. Excessively long cooking or frying foods increases the loss of nutrients. Therefore, in order to better preserve them products when cooking should be laid into boiling water.

The initial composition of fats during the heat treatment also undergoes certain changes. When cooking meat products, fat melts and most of it is collected on the surface in the form of tiny balls. In contact with boiling water, conditions are created for its hydrolysis. During heating to high temperatures the content of biologically active substances in fat decreases. Oxidation is influenced by the material from which the equipment is made, for example, cast iron is more active than stainless steel.

Assessment of the quality of meat and meat products

The quality of meat and meat products is evaluated by food, biological and energy value, organoleptic indicators and sanitary and hygienic (mainly microbiological) safety. The nutritional value of meat products is their ability to satisfy the vital activity of the human body. It is characterized by the content of nutrients in the product, their ratio and degree of assimilation. The content of proteins, fats, vitamins, minerals, etc. is determined by conventional methods. The biological value of meat products is determined by the content and ratio of essential amino acids and essential unsaturated fatty acids, biologically active and mineral substances that are absorbed by the human body.

Amino acids and fatty acids are determined by the chromatographic method. Others - by conventional methods. Energy value meat products is determined by the amount of energy that is released in the human body during metabolism. It is quantitatively determined analytically: the content of proteins, fats, carbohydrates is multiplied by the coefficient of energy value of each component in kcal / g. For fats, the coefficient values ​​are 9 kcal/g, for proteins and carbohydrates - 4 kcal/g each.

The safety of meat products is determined by the absence of substances harmful to the human body: salts of heavy metals, radionuclides, nitrites, preservatives, pathogenic microorganisms, toxic substances released by microorganisms, and impurities (glass, metal, etc.). All sausages and salted meat products must be manufactured in accordance with the requirements of state standards and specifications. The quality of the finished product is determined organoleptically and by laboratory studies of physical, chemical and microbiological indicators.

During the organoleptic evaluation of the selected samples, the appearance, texture, taste and aroma, freshness of the product, uniformity of bacon distribution, and color in the cut are evaluated. Physico-chemical and microbiological studies are carried out by the laboratory of the enterprise. In sausage products it is regulated mass fraction moisture, salt, sodium nitrite, starch. The content of toxic substances, microorganisms, aflotoxin B1, nitrosamines, hormonal drugs, heavy metals and radionuclides, pesticides, etc. should not exceed the levels of current standards. Based on quality assessment sausage products the commission issues a certificate of their quality and a permit for sale indicating the date and hour of release of products from the enterprise and the timing of its sale under appropriate storage conditions.

In a natural casing, boiled sausages, frankfurters and sausages are stored at a temperature of 2 to 6°C. Shelf life boiled sausages And meat loaves premium up to 72 hours, 1st and 2nd grades and liver sausages the highest grade - up to 48 hours, boiled sausages of the 3rd grade, liver sausages of the 2nd grade - up to 24 hours, liver and blood sausages of the 3rd grade - up to 12 hours. When using polyamide casings, the shelf life increases by 2-3 times. store semi-smoked sausages at a relative humidity of 75-78% at a temperature of 12°C up to 10 days. At temperatures from 0 to 6°C - 15 days, at minus 9°C - 3 months. Cooked smoked sausages can be stored at temperatures up to 15°C - up to 15 days, from 0 to 4°C - 1 month. and at minus 9°С - 4 months. Raw smoked sausages at temperatures up to 12°C, they are stored for up to 4 months, and at minus 9°C - up to 9 months.

The slaughter weight of pigs is divided into food and technical products. In addition, endocrine-enzymatic and special raw materials are isolated

Pig slaughter products:

Carcass (meat on the bone) - the body of a pig without a skin or processed by the method of scalding in the skin, as well as with the croup removed, without a head, legs, internal organs and internal fat;

Offal of the first category - liver, kidneys, tongue, trimmings, brains, heart;

By-products of the second category - stomach, calf, tail, lungs, trachea, spleen, legs, ears, head without tongue and brain;

Raw fat - adipose tissue obtained during the processing of pigs is a raw material for the production of rendered fats

The composition of raw fat includes internal fat, lard, mezdra-tion and intestinal fat, internal fat - raw fat removed from the internal organs of pigs; fat - subcutaneous fat of pigs; skin fat - the residue under the skin fat, removed from the inside pork skin; intestinal fat - fat skimmed from all types of quisho.

Technical products for pig slaughter:

The skin of pigs - freed from skin fat and marginal areas;

Technical blood - blood unsuitable for food purposes, but approved by the veterinary and sanitary inspection for feed purposes;

Technical rendered fat - animal fat obtained from raw fat unsuitable for food purposes, approved by veterinary and sanitary supervision for use for feed and technical purposes;

Non-edible raw materials from the slaughter of pigs used for the production of dry feed of animal origin - trimmings from carcasses, genitals, embryos, waste obtained from the processing of offal in and quisho.

Endocrine, enzyme and special raw materials:

Endocrine raw materials - endocrine glands and some glands with internal and external secretion, are raw materials for the production of organ preparations;

Enzyme raw materials - glands that have only external secretion, as well as organs and other raw materials of animal origin used for the production of enzymes and enzyme preparations;

Special raw materials - some types of animal organs and tissues used for the production of organoleptic preparations. Special raw materials include pechinqua, blood, bile, spinal cord, double-glazed windows, one body of eyes, embryos, etc.

The age of pig carcasses is determined by the thickness of the subcutaneous fat above the spinous processes of the 6th-7th thoracic vertebrae (GOST 1213-74). Carcasses of the first category must have a subcutaneous fat thickness of 1.5 to 3.5 cm.

To determine the virility of subcutaneous fat along the ridge, the thickness of subcutaneous fat is measured at the withers, over the spinous processes of the 6-7th thoracic vertebrae, over the first lumbar vertebra and sacrum. Based on the sum of these measurements, the average thickness of subcutaneous fat is calculated. Fat thickness is measured with a caliper or ruler with an accuracy of 1 mm (excluding skin thickness).

The quality of meat is understood as a set of properties that show the suitability of meat for nutrition, they include indicators of usefulness (food and biological) and sanitary and veterinary safety (d good quality and safety.

Good quality is understood as the absence of spoilage processes in meat (rotting, oxidation, rotting, mold, etc.). Safety indicators - the absence of bacteriological, chemical, mechanical pathogens (pathogenic microbes, fungi, helminths, toxins, mechanical impurities, etc.) in the meat.

The identification of all these indicators during the examination of meat is the veterinary and sanitary assessment of livestock products.

The main indicators of meat quality, which are of particular interest to the consumer, are the color, taste, aroma, juiciness and tenderness of the meat. IN modern conditions the quality of meat is evaluated in a complex way - quality and safety. ECU. Only such a comprehensive assessment can guarantee the sanitary quality of meat.

in accordance with modern international requirements for quality and safety food products in connection with the need for the production and sale of benign veterinary and sanitary products of animal origin. State Department of Veterinary Medicine, approved mandatory minimum research of raw materials, animal products and plant origin that should be carried out in the laboratory x veterinary medicine.

The presence of coloring substances in meat (90% myoglobin and 10% hemoglobin) mainly determines the color of the meat. The intensity of the color of the meat is determined by the type, breed, sex, age, method of fattening animals, as well as the conditions and duration of storage and the processes of its maturation. The color of the meat depends to a certain extent on the pH. Pork at pH 5.6 has a pink-red color, and at pH 6.5 and above it is darker. The pink-red color of the pork corresponds to a good bleeding of the carcass and fresh meat. The appearance of a green color is associated with the formation of sulfomyoglobin as a result of the reaction of myoglobin with hydrogen sulfide, which is formed during the breakdown of sulfur-containing proteins by microflora.

The main indicators of the quality of meat are its taste and aroma, which are settled due to the content and a certain ratio of extractive substances in the meat, which are easily oxidized, as they are unstable to high temperatures. The taste and aroma also depend on the age, sex of the animals, the ratio of tissues, the amount and distribution of fat, etc. In the meat of young animals, these quality indicators are less than in the meat of wild animals. The taste of meat that is obtained from overworked animals deteriorates.

The smell or taste of meat also depends on the sex of the animals (bulls, boars), the composition of the diet, especially when feeding fishmeal and fish waste.

The consistency of meat depends mainly on its tenderness, juiciness and softness. It has been established that juiciness, tenderness, taste and other merchandising and technological properties depend on the moisture content of meat. Therefore, knowledge of these features of meat in its various states and during storage is of great practical importance. The meat is darker in color, more juicy, loses less mass during cooking. A high pH value increases the water-retaining property of the meat. At a pH of 6.8, the tenderness of the meat is most pronounced and decreases with a decrease in the marbling of the meat.

The nutritional value of meat is its property in its chemical composition to correspond to the formula balanced nutrition(protein 1, fats 1.2, carbohydrates 4.6). The nutritional value of meat is shown in. VMI-sti in it proteins, fats, vitamins, mineral, extractive and other biologically active veins.

biological value meat is characterized by the quality of its protein components and is manifested by the degree of nitrogen retention of meat in the body of animals growing

It depends on the amino acid composition of meat proteins, its balance, digestibility and other structural features of proteins.

The energy value of meat is determined by the part of the energy that is released from meat in the process of biological oxidation and provides the physiological functions of the body (kcal or kJ)

Commodity assessment of meat is carried out according to. GOST 7724-77 "Pork meat in carcasses and half carcasses" The standard applies to pork meat in carcasses and half carcasses, pig meat intended for retail trade, public catering networks and for industrial processing for food purposes.

Pork is marked with the appropriate forms of marks: the first category (bacon) - with a round mark with a diameter of 40 mm, the second category (meat) - with a square mark with a side size of 40 mm;

the cutting of carcasses in trade is carried out in accordance with. GOST 7597-55, as a result of which two varieties of meat are obtained

The anatomical boundaries of carcass cutting include:

1 - shoulder blades. The boundaries of the compartments pass: a) the back - in a straight line between the fifth and sixth dorsal vertebrae with the intersection of the ribs b) the bottom - through the humero-ulnar joint

2 - dorsal part. The boundaries of the compartments are: a) anterior - along the line of separation of part of the scapula; b) posterior - in front of the first lumbar vertebra; c) lower - across the ribs at about half their width.

3 - brisket. The boundaries of the compartments are: a) anterior - along the line of separation of the part of the scapula; b) posterior - behind the last rib; c) upper - along the line of separation of the dorsal part

4 - lumbar part of the flank. The boundaries of the compartments are: a) anterior - along the line of separation of the dorsal part and brisket; b) posterior - along a straight line passing between the last and penultimate lumbar vertebrae directly in front of the pelvic bone.

5 - ham. The boundaries of the departments are: a) front - along the line of separation of the lumbar part c. Pashin b) back - along the line of separation of the shank

6 - forearms (knuckle). Separates in a straight line through the glenohumeral joint

7 - the shank is separated from the ham in the transverse direction through the upper third of the tibia

Pork is characterized by high nutritional value; it is used for cooking first and second courses, a large assortment of sausages, hams, ham, rolls, boiled pork, loin, brisket and many other products that are in demand among the population. It is well preserved by salting and smoking. Lightly salted pork, stew and other canned food retain their attractive appearance and good luscious qualities for a long time. digestibility pork meat reaches 95%, fat - 98%. The calorie content of 1 kg of pork of average fatness is 8100 kcal, while beef and lamb of medium fatness are 1500-1550 and 12001300, respectively. KUA kcal.

Table 9 shows the average chemical composition various kinds pork - meat, bacon and fat, and in table 10 - the average chemical composition of individual cuts of pork

. Table 9

. AVERAGE. CHEMICAL. COMPOUND. PORK

					Energy value
	g per 100 g of product
bacon

Pork, compared to beef and lamb, contains less water and more dry matter. In addition, pigs are characterized by a greater slaughter yield. So, the mass of meat on the bones (without head, legs, skin and internal fat) is 58-70% in pigs, 48-55% in cattle and 38-50% in sheep.

Pork meat has a high content of complete and easily digestible protein, essential amino acids. It has less, than in other types of meat, such defective proteins as collagen and elastin.

. Table 10

. AVERAGE. CHEMICAL. COMPOUND. INDIVIDUAL CUT

					Energy value of 100 g, kJ
Brisket unedged

The carcasses of fat fat pigs contain more sarcoplasmic proteins, and the carcasses of lean pigs contain more myofibrillar proteins. The number of these protein fractions increases with an increase in the mass of TV. Varin. With a strong depletion of animals, the diameter of the fibers decreases by 2 times and the meat becomes tough, since it increases specific gravity connective tissue. The proteins of the muscle tissue of pigs are various. BOO levels differ in amino acid content. At the same time, with an increase in the fat content of pork and a decrease in the amount of protein, the amino acid content decreases accordingly.

The nutritional value of pork depends on the content of tissues in the carcass (Table 11)

. Table 11

. COMPOUND. Tissue carcasses of pigs

Fats. The presence of adipose tissue gives pork high calorie content, makes it tender, fragrant, but an excessively high amount of fat in pork leads to a relative decrease in protein content and a decrease in its nutritional value.

Pork fat compared to beef and lamb fat has best taste, good digestibility and is high-calorie product. The biological value of intramuscular and subcutaneous fat of pigs is determined by the high content of essential polyunsaturated fatty acids, especially arachidonic, and deficient vitamins (A and. E).

Minerals. Tables 12 and 13 show the content of minerals and vitamins in pork

. Table 12

Pork differs from the meat of other domestic animals in a high content of vitamins of the group. IN

. Table 13

Organoleptic characteristics of pork and products of its processing. For a comprehensive characterization of the quality of pork and products of its processing, it is necessary to determine the intensity of color (color), taste and aroma, tenderness, texture, juiciness, moisture capacity, etc.

The normal color of meat in pigs of a smaller mass is pink, in a larger one it is dark pink. Pale coloration of meat in fattened pigs indicates the presence of a defect in meat quality. RBE. Such light-colored pork is not tender enough in texture, watery and is characterized by reduced technological properties and increased losses during cooking and processing.

The taste and smell of pork, as well as other types of meat, are determined by the content of nitrogenous extractive substances in it, which are a product of protein metabolism. The factors that affect the taste of pork include the content of intramuscular fat (marbling), the ratio between muscle and adipose tissue. The taste and smell of pork is determined by tasting.

The tenderness of pork meat is determined to a large extent by the quantity and quality of connective tissue in muscle bundles, the content of intramuscular fat, and the diameter of muscle fibers. At elevated content in meat and connective tissue, tenderness is reduced.

An important property of meat is its moisture content, which is determined by the amount bound water contained in it. The more bound water in the meat, the better its technological properties.

One of the most reliable ways to change and control the quality of pork is selection. The theoretical prerequisite for breeding to increase the meatiness and improve the quality of pork is the high heredity of traits, which is characterized by the coziness of the meat qualities of pork, as well as their close relationship. This is the basis for successful selection and selection of animals in the desired direction.

All signs that determine the taste and presentation of pork (water-holding capacity, color, tenderness, marbling) are high-decay indicators

Meat color (0.71), water-holding capacity (0.59), tryptophan content (0.58) and muscle fiber area (0.54) are inherited to a high degree, fat content in g is somewhat worse

Meat good quality has a water-holding capacity in the range of 53-66%

Bilkovoyakisny indicator (the ratio of tryptophan to hydroxyproline) varies in different breeds of pigs in a fairly wide range (from 6.65 to 10.73)

breed differences in pigs significantly affect the quality of pork. Thus, pigs of the Large White, Landrace, Mirgorod, Welsh breeds differ both from each other and from their crossbreeds in terms of meat yield, lard, “muscle eye” area, bacon thickness and other indicators (Table 14m (Table 14) .

In animals of the sebaceous direction of productivity, as the most early, the period of intensive growth of muscle tissue is approximately 1-2 months shorter than in meat breeds, and the process of enhanced fat absorption begins much earlier. Therefore, having reached the same age, their carcasses have a different morphological and qualitative composition. With an increase in live weight in the body of pigs, the thickness of the fat increases, as well as the amount of meat and fat. However, the amount of fat increases faster than the amount of meat. This is especially clearly observed during the period of increase in live weight from 80 to 130 k0 kg.

With intensive fattening of pigs up to a live weight of 140 kg, their carcasses contain more fat than meat. Therefore, in order to obtain a carcass with a high meat content (52-54%), it is recommended to slaughter pigs when they reach. They have a live weight of 110-120 kg, and to obtain fatty pigs with a back fat thickness of more than 40 mm and a fat content in the carcass of 40%, they can be fattened to a live weight of 130-150 kg.

With age, the moisture content in the meat of pigs decreases and the content of fat and protein increases, the specific gravity of fat increases with a simultaneous decrease in the mass of meat and bones

Landrace in comparison with the Large White breed in all age periods are characterized by a high content of muscle and bone tissue in carcasses and a lower content of fat

. Table 14

breed. DIFFERENCES. PIGS for meat. INDICATORS

Different intensity of growth of individual tissues in the same age periods in animals of the Large White breed, Landrace and their crossbreeds significantly affects the quality of the ink obtained from them (Table 15)

. Table 15

slaughter and meat qualities of pigs of large breeds. WHITE, Landrace and their crosses for bruises. At 100. KG

Indicators
	Big white	Big white x landrace	Landrace x large white
Weight before slaughter, kg
Slaughter Yield%
Average fat thickness, mm
Weight of chilled carcass, kg
Yield cuts% to carcass weight
Part of the shoulder blade
Brisket
Lumbar part from a flank
Bucky, shank, shank

With an increase in the meatiness of animals, the pork obtained from them becomes watery, tough (the content of interfascicular and intrafascicular fat drops sharply in it), with a greatly reduced water-holding capacity and paler. In terms of protein content, there are practically no differences between groups of animals that differ in the content of meat in carcasses, while the content of tryptophan increases with an increase in the meat content of pigs.

Correlations between fleshiness and meat quality indicators have been established. Between the output of meat in the carcass and the content of intramuscular and intermuscular fat, as well as the content of bound water, a negative correlation is observed, and between the content of moisture and tryptophan - positive.

Improving the quality of carcasses and products of slaughter of pigs is achieved by the following selection methods: by intrabreeding selection, interbreeding, as well as interlinear and breed-linear. Hybro idization.

In each breed there are significant intrabreed opportunities for breeding to improve meat qualities. As a result of long-term purposeful work, new and radically improved existing breeds of pigs have been bred in the direction of improving their fattening and meat qualities. Breeding and breeding methods are being improved in general, and on this basis, new zonal and factory types, specialized and factory lines of pigs, characterized by high fattening and meat productivity, have been created in many areas of the country.

Feeding is the main factor that ensures the growth and development of the body of pigs, their performance, adaptation to exposure external environment and ultimately affects the quality of carcasses and the chemical composition of tissues

By adjusting the level and diet of pigs, a significant change in their body composition can be achieved.

Reduced dietary energy levels by 30% compared to existing regulations leads to an increase in the yield of meat in the carcass by 56% and a decrease in the amount of fat by 6-13%, and a 15% decrease in the energy level by 3.0 and 3.5, respectively.

A 15% increase in energy levels over normal increases fat yield by 3% and reduces meat yield by 2%. The calorie content of 1 kg of minced meat prepared from meat and lard after carcass deboning is lower by 12.5% ​​with a decrease in the level of nutrition of a piglet by 30% and by 5% - with a decrease by 15%.

With a decrease in the energy level in the diet by 15-30%, the thickness of the fat decreases by 3-12% and the area of ​​\u200b\u200bthe muscle eye increases by 6-13%, as well as the specific gravity of the carcass by 1-3%, the iodine number of fat increases, indicates a shift towards increase in fatty acids. The refraction number of fat does not depend on the level of feeding.