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Introduction. Various cultures of microorganisms have recently been used to accelerate technological processes. In this regard, it appears highly relevant to study the action of beneficial microorganisms on the components of food systems. Study objects and methods. The study objects included a model mixture of beef muscle and pork fat tissue with 2% salt, as well as a model protein. Lactobacillus plantarum and Staphylococcus carnosus were used in an amount of 1×107 CFU/g of raw material. The compositions of free amino and fatty acids, carbohydrates, and other components were analyzed by liquid and gas chromatography with mass-selective detection. Results and discussion. We studied the effect of L. plantarum and S. carnosus on protein, lipid, and carbohydrate components of food systems based on animal raw materials. We found that the combined effect of the cultures was by 25% as effective as their individual use at 4×109 CFU/kg of raw material. The three-week hydrolysis of proteins to free amino acids was almost a third more effective than when the cultures were used separately. The synergistic effect of L. plantarum and S. carnosus on fat components was not detected reliably. Free monosaccharides formed more intensively when the cultures were used together. In particular, the amount of free lactose almost doubled, compared to the cultures’ individual action. Conclusion. We described culture-caused quantitative changes in the main components of animal-based food systems: amino acids, fatty acids, carbohydrates, and basic organic compounds. Also, we identified substances that can affect the taste and aroma of final products when the cultures are used together or separately. These results make it possible to obtain products with a wide variety of sensory properties.

The process of obtaining copolyimides by polycondensation based on 3,6-diaminoacridine, 9,9-bis-(p-aminophenyl)fluorene, dianhydride of 2,2-bis-(3,4-dicarboxyphenyl)-1,1,1,3,3,3-hexafluoropropane and dianhydride of 3,3',4,4'-tetracarboxydifenyloxide are described. The main physico-chemical properties of the obtained products are discussed and the prospects for the use of these soluble and fusible products as a polymer base for the preparation of composite materials are shown.

The work is devoted to a review of works published in recent years on the development of the chemical structure of soluble and hot-melt copolyimides, including a brief description of their synthesis and properties.

A brief review of the prehistory of the appearance of an outstanding discovery in the field of physics and chemistry - the creation of the Periodic Table of Chemical Elements by the Russian scientist Dmitry Ivanovich Mendeleev is presented. He also first formulated a periodic law, on the basis of which the classification of the sections of the elements in modern chemistry was built. [ABSTRACT FROM AUTHOR]

The effects of salt on oxidative changes in fat and heme pigments were evaluated. The back fat was salted with sodium chloride in the presence of the hemoglobin. The indicators of the hydrolytic and oxidative spoilage were investigated in the samples of back fat from White Large pigs at two years of age. The proportions of heme and non-heme iron, as well as the content of metmyoglobin were determined in the samples of m. Longissimus dorsi from two-year-old female Large White pigs. Back fat salting did not significantly affect the acid value of back fat. Addition of salt in amounts of 3.5 % and 5.0 % initiated the oxidative changes. Addition of sodium chloride initiated fatty acid oxidation in the presence of the heme pigments. The content of unsaturated acids decreased by 22.8 % when 5.0 % of salt were added. The proportion of heme iron increased by 6.5 % relative to free iron when 5.0 % of sodium chloride were added. The positive correlation between the metmyoglobin content and the thiobarbituric acid value was found with the correlation coefficient of 0.98. [ABSTRACT FROM AUTHOR]

An alternative technology for filling cellulose materials with synthetic mineral nanodispersed filler is proposed. Composite polymer compositions for the introduction into cellulose material have been developed. A multifactor experiment was performed using the regression equations. Based on the mathematical processing of the experimental data, the properties of the developed composite nanodispersed compositions were found to depend on the ratio of their components. [ABSTRACT FROM AUTHOR]

The molecule relaxation characteristics of natural biopolymeric systems as which used wood of coniferous breeds was investigated by method of the thermomechanical analysis. The interrelation of topological changes of structure of a pine at presence iron nano particles relaxated under loading in conditions of a variation of humidity of system is revealed. It is shown, that at formation of a pseudo-grid of matrix structure, high-temperature amorphous blocks of a pseudo-mesh structure and cluster blocks with units of a branching of a pseudo-grid are consistently shown cluster blocks with molecular weights Mcw 240 - 28,000 as is amorphous-structural formations with a matrix of a pseudo-mesh structure. The revealed temperature transitions have allowed to establish the influence of drying and introduction ferriferous nano particles on formation of bio structures of wood. [ABSTRACT FROM AUTHOR]