Food fat content is one of the most controversial factors from a consumer’s point of view. Aim: (1) The trends in consumer attitudes towards pork and the fat and meat compositions in Duroc and Altai meat breeds and Livny and Mangalitsa meat and fat breeds were studied. (2) Methods: Netnographic studies were used to assess Russian consumer purchasing behavior. Protein, moisture, fat, backfat fatty acid content from pigs, longissimus muscles, and backfat from (A) Altai, (L) Livny, and (M) Russian Mangalitsa breeds were compared with those from (D) Russian Duroc. Raman spectroscopy and histology were applied to the backfat analysis. (3) Results: The attitude of Russian consumers to fatty pork is contradictory: consumers note its high fat content as a negative factor, but the presence of fat and intramuscular fat is welcomed because consumers positively associate them with better taste, tenderness, flavor, and juiciness. The fat of the ‘lean’ D pigs did not show a “healthy” fatty acid ratio, while the n-3 PUFA/n-6 PUFA ratio in the fat of the M pigs was the best, with significant amounts of short-chain fatty acids. The highest UFA content, particularly omega 3 and omega 6 PUFA, was found in the backfat of A pigs with a minimum SFA content. The backfat of L pigs was characterized by a larger size of the adipocytes; the highest monounsaturated and medium chain fatty acid contents and the lowest short-chain fatty acid content; the ratio of omega 3 to omega 6 was 0.07, and the atherogenicity index in L backfat was close to that of D, despite the fact that D pigs are a meat type, while L pigs are a meat and fat type. On the contrary, the thrombogenicity index in L backfat was even lower than the D one. (4) Conclusions: Pork from local breeds can be recommended for functional food production. The requirement to change the promotion strategy for local pork consumption from the position of dietary diversity and health is stated.

By-products are the potential source of animal protein obtained from brood chickens and egg-laying hens. Certain by-products like gizzards and combs are quite tough and possess low nutritional and biological value due to their high content of connective tissue. Biotechnological processing improves the quality parameters of collagen-containing by-products. In this article a probiotic starter culture of propionic acid bacteria, which have high proteolytic activity, was used to treat the gizzards and combs of brood chickens. Before processing of by-products with starter culture, physical and chemical parameters and the yield of by-products in relation to poultry live weight were analyzed and recorded. 5%, 10% and 15% starter culture were added to the tested samples of chopped by-products, the samples were kept at a temperature of 30 °C, and every 4 hours the following functional and technological parameters were monitored: moisture binding capacity, water holding capacity (MBC and WHC) and yield of the product after heat treatment. The results proved that increase of starter culture amount and longer exposure of by-products to hydrolysis led to decrease of functional and technological parameters values, but for the combs those parameters remained at a sufficiently high level compared to the gizzards, as the gizzards were exposed to more intense hydrolysis than combs. The decrease in the pH value correlated with the dynamics of MBC and WHC changes; and dynamics of the product yield after the heat treatment. Also the stained histological preparations were studied in order to assess the influence of biotechnological processing on by-products microstructure, where significant differences were found in the morphological structure of muscle and collagen fibers of hydrolysates of combs and gizzards exposed to action of bacterial concentrate. The results of rheological studies showed that hydrolyzed chicken combs differed from gizzards; the combs were denser and featured more elastic structure due to a lower degree of hydrolysis by bacterial enzymes. In general, the properties of collagen-containing by-products (muscular gizzards and combs) change significantly after being exposed to enzymes of propionic acid bacteria.

This article addresses the issue of heterocyclic aromatic amines (HAA) accumulation during the process of heat treatment of meat products. There are methodological conditions of HAAs determination using high performance liquid chromatography with mass-spectrometer detection. During the research the most important factors that affect HAAs formation in meat products were identified. The most important factors are heat treatment duration, product contact with the heating surface, and temperature of the heat treatment should be above 150 °C. During research work, the information about HAAs concentration in beef, chicken and pork was obtained. The highest amount of HAAs was formed in beef, in the same time the lowest concentration was detected in poultry. Also the relation between heat treatment duration and HAAs concentration was identified every 5 mins of heat treatment leads to an increase of about 50% of HAAs concentration. Studies have shown that HAA are unique products of post-translational modifications occurring in animal proteins, which can be formed as a result of a biochemical condensation reaction of carboxyl and amine compounds. Safe products manufacturing is impossible without studying the ways of metabolism of protein and the mechanisms of action of organic contaminants.

Dorogov’s antiseptic stimulators (fractions 2 and 3) are products of meat and bone meal pyrolysis that are used to treat farm animals. However, there is a lack of detailed information about their chemical composition. We aimed to study individual compositions of organic substances in the water- and oil-soluble condensates of these preparations. Dorogov’s antiseptic stimulators ASD-2F and ASD-3F (Agrovetzashchita, Russia) were used as samples of the water- and oil-soluble condensates of meat and bone meal pyrolysis. Volatile substances were identified by gas chromatography and gas chromatography-mass spectrometry, while amino acids were determined by high-performance liquid chromatography. The initial water-soluble condensate contained ammonium salts, amides of carboxylic acids, N-heterocyclic compounds, hydantoins, amino acids, and dipeptides, with a total content of 8% of the condensate’s weight. Its dehydrated concentrate had almost no ammonium salts and amides of carboxylic acids, but its contents of hydantoins, amino acids, dipeptides, and lowvolatile nitrogen-containing heterocycles were 10–15 times as high as those in the initial condensate. The condensate contained 13 dipeptides and 19 amino acids with a total content of 2.5%. According to gas chromatography-mass spectrometry, the oilsoluble condensate contained over 30% of nitriles; 7–10% of higher and aromatic hydrocarbons, phenols, and amides (with esters); and 1–3% of N-heterocyclic compounds, naphthalenes, pyridines, and dipeptides. The nitrogen-containing heterocycles, as well as dipeptides, were similar to those in the water-soluble condensate. We identified 80% of individual organic substances in the water-soluble pyrolytic condensate. Together with its concentrate, they contained more than 220 organic substances divided into 10 main groups. The oil-soluble condensate consisted of over 350 individual organic compounds. The full composition of the preparations can be further identified by three-quadrupole liquid mass spectrometry.

ФГБНУ "ВНИИМП им. В.М. Горбатова"

Steaks weighing 150.0±1.0 g and 2.5 cm thick were formed from chicken, pork and beef. After steaks formation they were fried using electric grill in temperature 230°C. First set of steaks were fried during 5 mins on each side, second one – during 7.5 mins, and the third set were fried during 10 mins on each side. After frying, steaks were tested for 2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 2-Amino-1-methyl-6-phenylimidazo(4,5-b)pyridine (PhIP) content. Analysis of HAAs was performed by HPLC system (Agilent 1200) with QQQ MC/MC detector (Agilent 6410B). The studies did not show a large difference in the total concentration of HAAs formed during frying of pork and beef, but the amount of HAAs in chicken is 1.5–2 times less than in pork or beef. This may be caused by the lowest fat content in poultry meat relative to other types of meat. At the same time, an increase in the duration of heat treatment by 2.5 minutes on each side increases the amount of HAA formed in the product almost by 1.5 times. Total amount of HAAs detected in fried chicken: 22.45, 35.76 and 54.36 ng/g for 10, 15 and 20 minutes of heat treatment duration. Total amount of HAAs detected in fried pork: 47.09, 73.68 and 112.39 ng/g for 10, 15 and 20 minutes of heat treatment duration. Total amount of HAAs detected in fried beef: 42.56, 61.91 and 92.21 ng/g for 10, 15 and 20 minutes of heat treatment duration. The results of HAAs content are shown in table 1. Research conducted as part of the state assignment of Gorbatov Federal Research Center for Food Systems of Russian Academy of Sciences 0585-2019-0007.