Food systems

Advanced search
Vol 2, No 1 (2019)
View or download the full issue PDF

4-8 337

The aim of the investigation was to study an effect of thermal treatment parameters on the content of reducing sugars, amino acids and acrylamide in the meat model system depending on the thermal treatment regime. The authors studied an influence of the reaction of melanoidine formation on the concentration of amino acids and reducing sugars at different thermal treatment regimes and established a decrease in the total amino acid content by 7 % upon the standard sterilization regime and by 11 % when increasing the temperature or duration of thermal treatment. It was found that at the same temperature with an increase in duration of thermal treatment up to 50 min., the acrylamide level increased by 1.6 times. Exposure of the model samples to a temperature of 120 °С for 50 min. had the highest effect on the level of acrylamide accumulation compared to the traditional sterilization regime of canned foods for child nutrition and the regime with an increased temperature of up to 130 °С. The obtained data will allow developing new meat products with the reduced content of unsafe components for nutrition in early childhood.

9-15 1285

Drinking water is important in food production. Its indicators have a direct impact on the quality and safety of finished products, the technological equipment efficiency, etc. In most food technologies, involving the use of milk powder, a priori use the process of its preliminary hydration, that is, dissolution or recovery. In this connection, there is a need to generalize the existing theoretical and practical foundations of this process and find ways to further improve them. Analysis of scientific and technical material in this area showed, that a number of scientists proposed various descriptions not only of individual stages, but also of the dissolution process as a whole, and its determining factors were identified, mathematical models were built, making it possible to determine critical areas depending on from the properties of the raw materials and the process, data were obtained on the parameters of the system during the dissolution of dry dairy products.

In the article presents the sanitary and hygienic, physicochemical and organoleptic require-ments for drinking water by Russian legislation, international organizations and national standards of a number of countries.

Presented a review of widely used and promising water treatment methods.

Analyzed data, describing the effect of the microelement water composition on the efficiency of milk powder dissolving process. It is shown, that decrease of water total hardness and dry substances of mass fraction adjustment in the reconstituted milk have a positive effect on the dissolution process efficiency.

Was noted the relevance of further researches on the directional formation of water trace ele-ment composition for increasing the efficiency of milk powder dissolving and to obtain re-constituted dairy systems, used in the production of various food products of predicted quality and safety.

16-19 271

The main sources of vegetable protein are seeds of legumes and oilseeds, which differ as by total content as by the quality. One of the least expensive and most rapid method of assessing the quality of protein is a chemical method, based on a comparative analysis of its amino acid composition, in particular, essential amino acids (EAA), and "ideal" protein. A widespread indicator of the proximity of the protein to the ideal is the minimum period, which shows how much of it can be used by the body for plastic needs (the main exchange and ensuring of body weight gain). Obviously, the more of this (convertible) protein in the product, the better (but not more than the daily value). One of the methods of obtaining a grain product with an increased convertible protein is blending, i.e. mixing in a certain proportion of different types of protein raw materials. In this case, the content of the converted mixture may be greater than in the components, and the excess less. The article presents a methodology for calculating the proportion of convertible protein in the product, as well as a new approach to the formation of effective mixtures. On the basis of this method, the results of the calculation of such mixtures on the example of a grain product with the use of collapsed white lupine, linseed cake and ginger seeds as components are shown. In all cases, there are rational proportions of the mixture, in which its convertible protein exceeds this figure in the component. The accuracy of the calculations largely depends on the accuracy of the total protein content and EAA.

20-22 286

The aim of the work is to study the inhibitory activity of the Streptomyces lucensis VKPM Ac-1743 and Streptomyces violaceus VKPM Ac-1734 strains stored at –18 °C in a 15 % glycerol solution and in a 0.9 % sodium chloride solution.

The object of the study was the actinomycete strains of S. lucensis VKPM Ac-1743 and S. violaceus VKPM Ac-1734 producers of glycosidase inhibitor, which is a micro-ingredient for creating products with a low glycemic index. The storage time was nine months. Bookmark storage was performed by flushing with a taped agar starchcontaining environment of Capek. For comparison, we studied the properties of cultures stored at +4 °C without cryoprotectant.

Deep cultivation of Streptomyces strains was carried out in a periodic manner on a medium containing corn starch hydrolyzate under the Multitron incubator shaker (INFORS,Switzerland).

Inhibitory activity was determined in inactivated native solutions by a colorimetric method with respect to pancreatic α-amylase, a test glycosidase involved in carbohydrate metabolism, and whose activity was chosen as a criterion for assessing the hypoglycemic action of the inhibitor. The proteinase activity of the inactivated native solution was determined by a modified method using a casein substrate.

The experimental data were processed using the methods of mathematical statistics and Excel XP programs.

As a result of the research, it was established that the actinomycete strains of S. lucensis and S. violaceus, the producers of glycosidase inhibitors, can maintain inhibitory activity during low-temperature storage for nine months.

For the S. lucensis actinomycete strain, stored in a 15 % glycerol solution at – 18 °C, the maximum inhibitory activity is 48 hours in the biotechnological process and is (3686 ± 300) IU/cm3 native solution, and for the violaceus strain – (3150 ± 200) IU/cm³ of the native solution, respectively.

For the strain of actinomycete S. lucensis, stored in 0.9 % sodium chloride solution at a temperature of – 18 °C, the maximum inhibitory activity accounts for 72 h of the biotechnological process and is (2600 ± 200) IU/cm³ of the native solution, and for the strain S. violaceus the maximum inhibitory activity accounts for 24 hours of the biotechnological process and is (3530 ± 200) IU/cm³ of the native solution.

At a storage temperature of +4 °C, the inhibitory activity for the strain of actinomycete S. lucensis is (560 ± 20) IU/cm³ of native solution, and for the strain of S. violaceus – (1747 ± 100) IU/cm³ of native solution, respectively. On the basis of the data obtained, it can be concluded that a temperature of –18 °C is preferred for long-term storage.

During the cultivation of Streptomyces strains, proteinase activity ranged from (0,012 ± 0,001) U/cm³ to (0,072 ± 0,002) U/cm³.

The obtained data can be applied in further studies to develop conditions for long-term storage of collection crops.

23-26 328

The aim of the present study is to explore the transformation of (1→3)(1→4)-β-D-glucans of rye biomass by Aspergills niger and accumulation of (1→3)(1→6)-β-D-glucans in the microbial cell wall.

Biomass from rye grain was obtained as a result of enzymatic hydrolysis of grain grinding of Omsk region of non-standard quality with grain impurity content of 45 ± 2 % by preparations (1→4)-β-glucanolytic, (1→3)-β-glucanolytic, (1→4)-xylanolytic and (1→4)-amylolytic action. Fermentation of hydrolysates, sucrosemineral and molasses medium by A. niger was carried out by a batch process under aerobic conditions. Determined the content of β-glucans, amino-nitrogen, glucose, disaccharides in grinding grain rye, rye biomass, the biomass of A. niger, the supernatants by colorimetric methods. Determination of chitin in biomass and qualitative determination of chitosan in supernatants of hydrolysates was carried out using chitosan sulfate sample and subsequent microscopy.

The results of the research showed that (1→3)(1→4)-β-D-glucans in grain grinding are 10.2 ± 0.2 % in terms of dry matter, which exceeds the content of polysaccharide in the grain of standard quality by 1.5 – 3 times. In rye biomass revealed their smaller amount, 6.4 ± 0.5 %, apparently, due to the action of (1→4)and (1→3)-β-glucanase, (1→4)-xylanase and (1→4)-amylase. In microbial mass A. niger content of (1→3)(1→6)-β-Dglucans were at the level of 21.7 ± 0.7 %.

On the basis of the obtained results, it was concluded that it is possible to use rye grain of non-standard quality, with a high content of grain impurities and a low proportion of starch polysaccharides, as a source of β-glucancontaining substrate for biosynthesis (1→3)(1→6)-β-D-glucans by A. niger having advantages over (1→3) (1→4)-β-D-glucans of plant origin. They are functionally more active and have a wide range of applications, namely as food additives in the manufacture of a wide range of products: for the enrichment of fibers, increasing the shelf life of products due to its water-binding properties, as thickeners, emulsifying and fat-reducing microingredients, stabilizers of creamy emulsions, textureformers, flavor enhancers.

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.

ISSN 2618-9771 (Print)
ISSN 2618-7272 (Online)