[Effect of ionizing radiation on microbiological safety and activity of antioxidant enzymes in minced meat].

A number of studies have shown the effectiveness of meat irradiation at doses of 2-6 kGy to extend its shelf life when stored in vacuum packaging. It is known that the radiation treatment of meat can lead to a decrease in the content of natural antioxidants. Furthermore, the intensity of oxidative processes is significantly higher in meat products with a high fat content (20% or more). At the same time, the optimal modes of minced meat irradiation, which make it possible to ensure safety for the population and to increase the shelf life, have not yet been established. The purpose of the research was to study the effect of various doses of ionizing radiation on the content of aerobic, facultative anaerobic microorganisms and radiolysis products, and the activity of antioxidant enzymes in chilled minced meat during storage. Material and methods. The object of the study was minced meat, consisting of beef and pork (1 : 1) with 20% mass fraction of fat. The experimental samples were irradiated on an electron accelerator UELR-10-15-S-60-1 with an electron energy of 5-10 MeV at doses of 2, 2.5 and 3 kGy. The control sample of minced meat was not subjected to radiation treatment. Determination of the total count of mesophilic aerobic and facultative anaerobic microorganisms (QMAFAnM) (CFU/kg) in control and experimental samples was determined on days 0, 7, 15 and 22. Methods for evaluating antioxidant activity included spectrophotometric determining the content of active radiolysis products that react with 2-thiobarbituric acid (TBA-AP) according to the Brajet method, total antioxidant capacity (TAOC) and activity of antioxidant enzymes in minced meat: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx). Results. Radiation treatment of minced meat at a dose of 2.0 kGy provided a normalized level of QMAFAnM in chilled minced meat for 22 days. It has been established that the treatment of minced meat with ionizing radiation in doses of 2.0-3.0 kGy leads to a dose-dependent decrease in its TAOC and the activity of antioxidant enzymes (SOD, CAT, GPx), as well as to an increase in TBA-AP content (р<0,05). Conclusion. The dose of ionizing radiation of 2.0 kGy helps to maintain the microbiological safety of minced meat for 22 days in terms of QMAFAnM with minimal changes in TAOC values, SOD, CAT and GPx activity and TBA-AP content.

[The distinctive characteristics of the nutrient composition of reindeer meat from the Vorkuta district determined by the conditions of the region of origin].

Reindeer meat is an important source of crucial nutrients (protein, fat, minerals) in nutrition of Arctic indigenous people. The authentic meat properties are formed under the influence of many factors, the main of which are the lifetime factors including the region of production and peculiarities of keeping. The regional peculiarities of the reindeer meat composition are quite poorly reflected in the reference books on the chemical composition of food products and in the scientific publications. The aim of the work was to evaluate nutritional value, the level of amino acids, fatty acids, minerals and trace elements of reindeer meat from the Vorkuta district. Material and methods. The objects of the research were the samples of reindeer meat (m. longissimus dorsi) from the Vorkuta district obtained from the highly productive semi-domesticated young reindeers of the Nenets breed. The samples were taken from free-ranging male animals at the age of 8-10 month. The amino acid composition was analyzed by the chromatographic method, the mass fraction of tryptophan by the spectrofluorometrically method, oxyproline by the spectrophotometric method. The content of minerals and trace elements was detected by the flame atomic absorption method. The lipid extraction from the average sample was carried out by the extraction with chloroform/ methanol by the Folch method, the purity of the extracted lipids was controlled by the method of thin layer chromatography. The fatty acid composition was determined the gas chromatographic method. Results and discussions. The indicators of the chemical composition of reindeer meat from the Vorkuta district were established. The content of protein was 23.0%, the content of fat 1.2%. The high content of tryptophan (0.628 g/100 g of the product) was characteristic for this prodact. The ratio of tryptophan to oxyproline was 11.8, which exceeded the values in pork and chicken. The low level of polyunsaturated fatty acids (17.8% of total lipids), in particular linoleic acid (6.9%), was assigned to the special features of the composition of meat under investigation. With that, quite high content of saturated fatty acids (48.6% of total lipids) was observed, which explained increased meat stability to oxidative spoilage during long-term storage and processing. The content of calcium in the reindeer meat from the Vorkuta district was 72.25 mg/kg, potassium - 33.3 g/kg, magnesium - 310.25 mg/kg, iron - 55.54 mg/kg, zinc - 41.89 mg/kg, copper - 4.0 mg/kg. The level of iron, magnesium and copper in this type of meat was significantly higher than the data on reindeer meat presented in the reference literature. Conclusion. The obtained data on the chemical composition of reindeer meat from the Vorkuta district can be a basis for the development of the indicators of its authenticity and in the future can be used for identification in case of the need to confirm species and a region of origin of meat, as well as for solving tasks of formation and promotion of regional brands.

[Development of a meat-based product for enteral nutrition].

Meat is a source of the most full value protein, which contains all essential amino acids, B group vitamins, minerals, including heme iron and zinc. The development of enteral mixtures produced on the basis of meat raw materials will allow leveling the problem of annoyance with the same product taste and extending an assortment of the supplied products for enteral nutrition. As a result of the experiments on the model and natural objects, the technology was developed for beef-based canned food intended for enteral nutrition of people in the post-operative period as well as in the conditions associated with appetite loss, mandibulofacial injuries, burning injury, chewing and swallowing impairments. The multi-component recipe modules balanced by fatty acid and amino acid composition, enriched with the vitamins and minerals were theoretically substantiated and realized. The minimal score was 0.99 unit fractions, coefficient of utility (0.83 unit fractions), coefficient of comparable redundancy 7.20 g/100 g protein. The obtained values of the balance criteria allow making a conclusion about approximation of the values to the physiologically necessary ratio. The correction of the fatty acid composition of the mixture models was carried out in order to increase the unsaturated fatty acid content by combination of meat fat with vegetable oils. The actual ratio of the fatty acid (SFA:MUFA:PUFA) in the product was 16.1:54.7:29.2, the ratio of omega-6 to omega-3 PUFA was 4:1. When designing the vitamin and mineral composition, the intensity of the thermal effect was taken into account. As a result, the doses for addition of vitamins were established with regard to their destruction during the technological process. Based on the performed research, the technology was developed for meat-containing canned food, adapted to the real conditions of the enterprises engaged in production of meat products for child nutrition. The product can be used as a basis or additional source of nutrition during the necessary period of nutritive support of patients.

[Assessment of clinical efficacy and tolerability of meat-containing canned food for enteral nutrition].

AIM OF STUDY: to evaluate the efficacy and tolerability of meat-containing canned food for enteral nutrition in clinical settings in patients with gastrectomy. The product was made from animal protein (beef) with the addition of vegetable oils, soy protein, maltodextrin, stabilizer, vitamins and minerals. 40 patients with gastrectomy were included to the study and randomly formed 2 groups of 20 persons: the main group (8 men and 12 women, mean age 64.4±12.4 years) on the background of standard mashed diet for 14 days received 2 portions of the tested product (240 ml), the control group (5 men and 15 women, mean age 64.8±12.9 years) was treated with standard diet. Daily registration of the symptoms was carried out filling the 5-point scale of the Likert (the presence and severity of abdominal pain, flatulence, heartburn, nausea, a feeling of heaviness after eating, incomplete evacuation of the intestine). The Bristol stool scale was used to assess the dynamics of the stool. Laboratory parameters (hemoglobin, blood serum level of total protein, albumin and iron) and body composition parameters were evaluated before and after treatment. Consumption of meat-containing canned food for enteral nutrition was accompanied by significant decrease in the severity of nausea (from 1.20±0.29 to 1.02±0.05 points of the Likert scale, p=0.017), a decrease in abdomen heaviness (from 1.8±0.8 to 1.4±0.6 points, p<0.05), contributed to an improvement in stool consistency, an increase in all body composition parameters, a positive dynamic of protein metabolism (increase of hemoglobin level from 119.2±9.6 to 122.6±6.8 g/l, p>0.05, blood serum protein and albumin). A tendency to increase the mental component of the quality of life (+4.2%) was found. Thus, meat-containing canned foods for enteral nutrition can be used in the diet of patients in the postoperative period, they are well tolerated in conditions with loss of appetite, are effective in patients with protein-energy malnutrition.

[Effect of polypeptides isolated from cattle abomasum on stomach regenerative processes in rats].

The effect of polypeptides isolated from cattle abomasum on regenerative processes of rat stomach upon simulating stomach mucosal damage caused by aspirin was studied. Experimental research was carried out on male Wistar rats with initial body weight of 230±20 g. The duration of the experiment was 22 days. The rats were divided into 4 equal groups (n=11). The first (control) group-consisted of the intact animals; animals from experimental groups 2-4 were intragastrically administered acetylsalicylic acid from the 1st to the 7th day for simulating stomach mucosal damage caused by aspirin (300 mg/100 g body weight). From day 8 to day 22, the animals were intragastrically adminitered the tested samples in the quantity of 2 ml per animal according tothe scheme: the 2nd group - distilled water, the 3d group - native abomasum extract; the 4 th group - thermally treated abomasum extract. Abomasum extract was obtained by extraction with 0,87% aqueous sodium chloride crushed abomasum and represented a liquid of cream color with protein mass content of 1,3 g/100 g of the product with high content of glutamic acid (15,5 g/100 g protein) and B-group vitamins. Electrophoretic analysis of the extract revealed several high molecular weight fractions in the range of 72 to 55 kDa. The bands with molecular masses 52, 43, 40, 37, 34, 26, 17 kDa were most pronounced; the intensive bands in the area 12 kDa and in the range lower than 10 kDa were revealed. The results of the conducted study show that the abomasum extracts both in the native and thermally treated form exert therapeutic action on animal with stomach mucosal damage caused by aspirin, have good antiulcer and gastroprotective activities upon stomach mucosa exposure to chemical damaging agents. The analysis of the hematological indices of the animals from the 3rd and 4th groups, which received the test samples after simulation, revealed the normalization of leukocyte, lymphocyte, granulocyte and monocyte content. This suggests the recovery of the animals after the disease. In the blood serum of these animals concentration of total bilirubin, cholesterol, triglycerides and glucose and the activity of gamma-glutamine transferase, ASAT and alkaline phosphatase decreased compared with those in animals with the model of stomach mucosal injury; while the total protein content, including the albumin fraction increased. The examination of the internal organs of the animals from the 3rd and 4th groups showed that the mucosal and submucosal membrane of the stomach were plicate, the signs of edema were absent, the hyperemia, any changes in mucosa, surface and glandular epithelium were not observed.

[Comparative characteristics of the composition and food value of Russian and imported canned meat for child nutrition]. / Sravnitel'naia kharakteristika sostava i pishchevoi tsennosti otechestvennykh i importnykh konservov na miasnoi osnove dlia detskogo pitaniia.

In the present review the brief features of main groups of domestic and foreign canned food are given. The special attention is paid to them ingredients and food value, which are decisive determinants at choice one or another kind of canned food for children.

[Unilateral epilepsy and the asymmetry of postepileptic sleep]. / Unilateral'naia épilepsiia i asimmetriia postépilepticheskogo sna.

In the paper the analysis is given of "penicillin" epilepsy in animals (cats) in conditions of different forms of deafferentation of one of the halves of the fore brain. It is shown, that in conditions of combined section of one half of the operculum of the midbrain and commissural systems of the endbrain, diencephalon and midbrain, under large doses of penicillin, unilateral convulsive activity is recorded in summate electrical activity of one of the brain halves at the side of the midbrain lesion. After the completion of unilateral organization of the epileptic process an asymmetrical sleep takes place: at the side, at which epileptiform activity was recorded, a more deep phase of the sleep appears than in the opposite brain half.

[Formation of neuronal reactions of the limbic cortex to visceral stimuli in the early ontogeny of the rabbit]. / Formirovanie reaktsii neironov limbicheskoi kory na vistseral'nye stimuli v rannem ontogenze krolika.

Studies have been made on age peculiarities of the evoked activity in neurones of the limbic cortex in response to visceral stimulation in rabbits from 4 age groups (1-8, 10-20, 23-35, 40-75 days). It was shown that from the earliest postnatal stages neurones of the limbic cortex exhibit high reactivity to sensory stimuli. In new-born rabbits, 86.8 and 70.1% of the neurones of the anterior and posterior limbic cortex respectively react to electrical stimulation of the vagal nerve. On further development of animals the number of reacting neurons increases, reaching 100% in 1.5-2 months old rabbits. Within all age periods, the predominant responses are presented by phasic activational and specific ones, the latter being of "on", "on-off" and complex patterns. Together with the development and changes of neuronal responses, evident dynamics of latent periods was noted, the average value of them decreasing 1.5-3 times for all types of neuronal reactions. The results obtained indicate early maturation of the neuronal mechanisms in the limbic cortex, which are involved into analysis of signals from the internal milieu of the organisms.

[Functional and morphologic characteristics of limbic cortex maturation during early ontogenesis]. / Funktsional'nye i morfologicheskie kharakteristiki sozrevaniia limbicheskoi kory v rannem ontogeneze.

Development of the limbic cortical area in postnatal ontogenesis of the rabbit comprises three periods judging by the parameters of impulse activity of neurones and cytoarchitectonic differentiation. The period of stratification and beginning of cellular differentiation functionally corresponds to the manifestation of simple forms of spike activity (single, group) with long inactivation periods (the first week of life). The period of intensive cytoarchitectonic differentiation with separation of the agranular type of the anterior limbic area structure correlates with a more complex neuronal impulse activity (burst discharges), augmenting spectrum of dominating spike frequencies, predominance of phasic activation and specific responses together with a high total neuronal responsiveness to sensory (acoustic) stimuli (the second to third week of life). The period of complete cytoarchitectonic maturation corresponds to the stabilization of functional properties of neurones (the fourth to sixth week of life). The revealed ontogenetic dynamics of morpho-functional reorganizations in the limbic cortex point to its involvement at an early stage of postnatal life in the mechanisms of sensory analysis and of the formation of adequate adaptive reactions.