Polyphenolic vegetable complexes are active antioxidants and play an important role in the processes of free radicals quenching in the human body. The aim of the work was to develop an immobilization method as a way for improving the stability of polyphenols in dried cowberry squeezing extract (DCSE) and to develop semi-finished minced meat products with antioxidant effect without changing their nutritional value. Experiments were carried out to study the nutritional value of DCSE. The presence of a large number of polyphenolic compounds in DCSE and a high radical-binding ability of the extract were revealed. Based on the mathematical planning method, an offal paste composition was obtained, which was used to obtain pellets, and the formulation of semi-finished minced meat products with pellets was optimized. It was established that preliminary immobilization of DCSE on offal pellets components allows to increase the level of total antioxidant content in the minced meat. Subsequent heat treatment of semi-finished minced meat products produced from such minced meat showed an increase in stability and, thus, bioavailability of antioxidants and the possibility of obtaining a finished product with antioxidant effect. The antioxidant effect of cowberry squeezing extract in the meat system is proved: accumulation of lipid oxidative decomposition products in the meat system during storage of frozen semi-finished minced meat products was inhibited to a greater extent when using offal pellets with immobilized compounds of cowberry squeezing extract. This work was carried out as part of the State Assignment of the Ministry of Education and Science of the Russian Federation No. 19.5486.2017/BCh and the «Young Scientists of ESSTU‑2019» grant.

Over many years, proteins and polypeptides have aroused scientific-practical interest due to multiple functions in the metabolic processes in the body upon vital activities. Biologically active substances of protein origin have wide application in different industries, including the food industry and medicine. At present, many studies are directed towards investigation of mechanisms of formation of such physiologically valuable food components as biologically active peptides and methods of their recovery from meat raw materials and meat products. A large part of literature data confirms that mechanisms of formation of such peptides are similar irrespective of methods of their generation. Their basis is enzymatic hydrolysis of muscle tissue proteins under the action of intracellular enzymes during autolysis, digestive enzymes of the human gastrointestinal tract or commercial enzyme preparations used in laboratories or in the industry. The method of culinary and/or technological processing also affects the process of biopeptide formation in meat products, namely, their recovery and availability.

Recently the actively active studies have begun devoted to the accumulation of «harmful» substances in food products, which are supposedly accumulated in the body of a person who often consumes these products. Meat, as a source of full-featured animal protein, is especially popular in this aspect. For the preparation of meat products various types of heat treatment are used, almost each of which will inevitably lead to the destruction of some of the chemical compounds originally present in the product, and the formation of completely new chemical compounds, which can often be harmful to the human body. During high-temperature heat treatment (mainly frying), some chemical reactions in meat products occur, which lead to the formation of heterocyclic aromatic amines (HAA) in it. Due to the great variety of raw meat and cooking recipes, during the heat treatment HAA’s of various classes are formed, each of them will be peculiar for the particular type of raw material or recipe components (with the exception of MeIQx and PhIP, which always form during frying). The more complete understanding of the HAA’s formation mechanism will help study the products of Maillard reactions and Strecker degradation. In this work we studied the formation of HAA’s as a result of the cyclization of creatine and the detaching of water (dehydration) from it during temperature exposure. The classification of the compounds formed as a result of these reactions is presented and the main classes of the HAA obtained in result are considered. The questions of the influence of various factors on amount of HAA formed, such as the fat content, the introduction of Fe²⁺, Fe³⁺, are raised. In the future it is necessary to conduct studies of the quantitative content of HAA in meat products to complement the already actively ongoing work on the study of xenobiotics consumed by humans with food, which will give a more comprehensive picture of the carcinogens content in food products.

During deep technological processing, DNA of food product components (specifically, in canned foods) is subjected to strong degradation, which makes the PCR-based food components identification more difficult. In this work, a primer-probe system is proposed, which was selected for the multi-copy region of long terminal repeat (LTR) of soybean (Glycine max). We confirmed its high sensitivity and specificity for soybean detection by real-time PCR. Using the selected system, we successfully analyzed the samples of meat-and-plant canned foods and other food products subjected to deep technological processing — tofu, preserved tofu, soy sauces, confectionary products containing soy lecithin. To compare with these samples, real-time PCR was carried out using the primer-probe system selected for the single-copy le1 gene. In terms of sensitivity, the use of the primer-probe system specific to the single-copy region was significantly inferior to the primer-probe system specific to the LTR region. The difference in the rate of degradation of these genomic DNA regions of Glycine max was found.

Sausages from poultry meat are present on the domestic market. In this regard, the problem of improving the competitiveness of these products is urgent. One way to solve this problem is to replace part of the raw meat in the minced meat for sausages with chicken egg products (pasteurized liquid egg, egg white, yolk). Using egg products as ingredients of minced meat will help stabilize minced meat for sausages before and after heat treatment, increase the nutritional value of the finished product, and reduce its cost. However, currently, the mass fraction of egg ingredients in meat and egg products formulations does not exceed 5–10 %. This is due to the appearance of a specific taste, if it is exceeded, and because it is impossible to obtain a pattern of egg fragments in the section of the finished products, if necessary. This fact restricts the use of egg products as ingredients of meat and egg products. A technological method to eliminate these problems is freezing egg ingredients before adding to minced meat. In order to control the application of this method, the mechanism of changes in frozen egg ingredients during the preparation and heat treatment of minced meat for sausages is revealed. It was found that at the stage of minced meat mixing, the liquid part of the egg ingredients resulting from the thawing of frozen particles surface mixes with meat ingredients. Moreover, when unmoved relative to the surrounding minced meat, the frozen particles of egg ingredients are caught by the minced meat, and then locally coagulate in the process of meat and egg product heat treatment. The weight of the liquid phase resulting from the thawing of frozen egg ingredient particle and the weight of its remaining local part depend on the duration of the minced meat mixing process, its temperature and particle weight. Based on the knowledge about this mechanism, analytical equations are obtained using the energy balance method. They describe the duration of egg ingredients thawing in meat and egg products depending on the particle weight and the temperature of minced meat. The experimental data of the authors are used as a basis for calculating the process of egg ingredients thawing. The proposed calculation method will allow purposeful controlling the process of change in frozen egg ingredients aggregative state in minced meat for sausages, under production conditions.