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Vol 4, No 1 (2021)
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4-11 430

The paper emphasizes the importance of not only the quantitative but also qualitative composition of protein in nutrition. The authors propose protein classification into three main groups according to the concept of reference (ideal) protein. A mathematical model is examined to solve the task of rational mixture production upon the given profile of reference protein. Two variants of the criterion for formation of optimal composition are described. One of them presents the classical sum of squares of the residual for essential amino acid scores and 1. The second also presents the sum of squares of the residual for essential amino acid scores and 1 but with regard to only those amino acids, which scores are less than 1. The minima of these criteria at the set of variants for the content of ingredients are taken as targeted functions. The algorithm and the program of calculation were realized in the program environment Builder C++ 6.0. The macro flowchart of the algorithm is presented and detailed description of each block is given. The program interface before and after the start of the calculation module is shown. The main windows and interpretation of the presented data are described. An example of realization of the proposed mathematical apparatus when calculating a food model composition is given. Plant components (white kidney beans, flax, peanut, grit “Poltavskaya», dry red carrot) were used as an object of the research. Most plant proteins were incomplete. It is possible to regulate the chemical composition including correction of a protein profile by combination of plant raw materials. Analysis of alternative variants demonstrated that minimum essential amino acid score in the first composition was 0.79 (by the first criterion), in the second 1.0 (by the second criterion); the reference protein proportion in the mixture was 10.8 and 13.5, respectively, according to the first and second criterion. The comparative results by other quality indicators for protein in the mixture are also presented: the coefficient of amino acid score difference (CAASD), biological value (BV), coefficient of utility, essential amino acids index (IEAA).

12-18 412

The objective of the study was to investigate the potential application of beta-glucans obtained from yeast sediment resulting from the manufacture of local Viorica wine (2018 harvest). To determine the amount of beta-glucans in the yeast sediment, two were used: the calculation method and the laboratory method, obtaining similar quantities, 29.92 ± 0.47 and 28.17 ± 0.32 respectively. The beta -glucans obtained were incorporated in various concentrations (0.1%; 0.2%; 0.3%; 0.4% and 0.5%) in the yogurt obtained from skimmed milk. The effect of beta-glucan addition on the physicochemical properties of freshly prepared yogurts was investigated. The addition of beta-glucans positively influenced the formation of the gel relay resulting in a decrease in the fermentation time of yogurt. The final pH point of 4.5 was reached one hour earlier (in 4 hours) compared to the control sample (in 5 hours). The results showed that there are no significant changes in physicochemical properties (titratable acidity, pH, viscosity and syneresis). The results obtained report that beta-glucans can be used as a thickening agent for low-fat yogurts by shortening the fermentation period and not essentially changing the sensory characteristics. Experimental results showed that the glycemic index of yogurt samples with the addition of beta-glucans have similar values in the range of 28-30. Respectively, the yogurts under study are attributed to food category with low glycemic index.

19-25 339

The article presents an analysis of the literature data on research related to the use of DNA technologies in the brewing industry. Significant relevance among them is the work on combating widespread falsification of food products, including alcohol. Classical methods of assessing the quality and safety of beer do not allow us to identify the substitution of raw materials declared by the manufacturer — one of the large-scale areas of falsification. Therefore, the question of applying new approaches to the assessment of the authenticity of brewing products is relevant. In particular, the most complete identification of falsifications in the alcohol industry is made by molecular genetic analysis methods. This article discusses the methods of extraction of nucleic acids, as well as markers used as genetic targets in the DNA authentication of alcoholic beverages. The analyzed material indicates the possibility of using molecular genetic methods based on the polymerase chain reaction as modern laboratory tools for determining the authenticity of manufactured goods. In addition, the potential of using DNA technologies in the fight against contamination of industrial enterprises has been identified.

26-30 380

Plants are a rich source of effective non-toxic biologically active substances. Various physicochemical methods of analysis are used for evaluation of plant antioxidant activity. Composition of ethanol extracts of red, yellow and white onion husks, dried rosemary, basil, and chaga were studied by high performance thin layer chromatography (HPTLC) method. The antioxidant activity of the obtained fractions on a chromatographic plate was assessed by subsequent DPPH screening. The extracts red and yellow onion husk and rosemary demonstrated the highest antioxidant activity, variability of the qualitative composition and similarity of antioxidant profiles, while extract of white onion husks did not contain any antioxidant classes. Intensive spots with Rf of 0.13-0.97 were observed along the whole chromatogram track corresponding to red onion husks. It was also found that all tested extract, excepting white onion husk and chaga, contained spots with varying degrees of intensity in the Rf range of 0.96-0.98, which corresponded quercetin Rf value.

31-39 305

In bakery water is used as a solvent for salt, sugar and other raw materials: for dough preparation, preparation of liquid yeast, starter cultures; goes for household needs cleaning of raw materials, equipment, premises, for heat engineering purposes — the production of steam necessary to humidify the air in proofing cabinets and ovens. Water plays an important role in the technology of delayed baking of bread products or in the technology of frozen semi-finished products: it is used during kneading to obtain an optimally developed gluten frame for better form and gas holding capacity; to obtain cold dough, which is the basis for slowing down the onset of the fermentation process, while fermentation should be minimized or completely absent; the amount of water affects the consistency of the dough for better dimensional stability during defrosting. Also, a low-temperature process, deep freezing strongly affects the structural and mechanical properties of the dough and the quality of the finished product; secondly, under certain parameters of freezing, the structure of the intracellular water of yeast can lead to a decrease in their activity, and even to the death of microorganisms. Therefore, the issues of the quality and quantity of water at any technological operation in bakery production with delayed baking are issues of the quality of finished products and therefore are very relevant.

40-44 230

The analysis of methods for determining the glycemic index (GI) of food products in vivo and in vitro. The authors note that the difference in the methodological approach to the determination of GI in vitro leads to obtaining results that are difficult to compare. A modified method for determining the GI for glucose is proposed, which is based on the method for determining the glycemic index for glucose, which makes it possible to assess the digestibility of various ingredients in products in terms of sugar load, and to calculate the glycemic index for glucose formed in the process of "digestion” of the test product in vitro. The modified technique provides for the use of digestive enzyme preparations: Acedin-pepsin and Panzinorm to provide a deeper "digestion” in vitro, providing a deep degree of hydrolysis of the main macronutrients in in vitro model experiments. The conditions for carrying out enzymatic hydrolysis reactions (temperature, pH, reaction duration) were selected experimentally. The studies carried out to determine the GI in vitro, according to the proposed method, showed comparable values, which indicates the possibility of using this method for the determination of GI in vitro. The results obtained should be considered as indicative, since the authors adhere to the position that the true value of the GI index can only be determined by blood analysis. But in this case, the value of GI is influenced by many factors, including the individual characteristics of the human organism.

45-55 248

The spectrophotometric method for measuring protein content can be used to evaluate the degree of proteolysis in cheeses. At a wavelength of 280 nm, tryptophan and tyrosine are absorbed, a high amount of them is found in casein, the main protein of cheese mass. It was found that the value of the absorbance coefficient of the solution of proteins extracted from flavoring additives with cheese flavor (FA) and cheeses depends on the degree of proteolysis of proteins in the cheese mass and differs in FA and different types of cheeses. The highest absorbance coefficient is observed in the FA samples A1%1cm = 10.30, in which from 65 to 81% of the protein is converted into a soluble state. In cheeses, the degree of proteolysis is from 23 to 33%, and the absorbance coefficient of solution is from 1.1 to 2.4 (with the exception of Cheddar cheese), which indicates an incomplete transition of amino acids absorbing radiation at 280 nm into the extract released from cheeses. Using the spectrophotometric method, the results of measuring the content of soluble protein in cheeses and FA, strictly correlating with the results achieved by the Kjeldahl method (R2 > 0.81), can be obtained. To get reliable results of evaluating the content of water-soluble protein in cheeses, it is necessary to carry out measurements on a sample of cheeses belonging to the same species group, having the same specificity of proteolysis and slightly different absorbance coefficient between samples within the instance.

56-61 325

The sanitary and hygienic safety of modern packaging is determined by the layer of packaging material in direct contact with the food product. This layer in most cases is a synthetic polymer of the polyolefin class — low density polyethylene. This material is used as a stand-alone packaging and in multilayer and combined packaging materials. During thermal and photooxidation, compounds can form in it that negatively affect the safety of the package, which can migrate into the product. Food technologies use methods of disinfecting packaging materials and packaging before filling or bottling products. These methods include ultraviolet irradiation of the surface, which has a bactericidal effect. Using spectral methods of analysis, researches have been carried out on changes in the polyethylene layers structure in the film’s composition, multilayer films and combined packaging materials when exposed to pulsed ultraviolet radiation in a wide spectral range (irradiation with a pulsed xenon lamp). Deformations of polyethylene macromolecules chemical bonds on the surface and boundary layers under the influence of pulsed UV-irradiation have been revealed. The IR spectra of ATR (Attenuated Total Reflection) were obtained, the analysis of which showed that the monofilm is subject to the greatest destructive effect, as evidenced by the appearance of characteristic absorption bands responsible for the formation of aldehyde, ketone groups, as well as for the polymer chain termination. It is shown that the use of food soot in the composition of multilayer packaging films blocks their photo destruction. Upon irradiation of a combined material based on cardboard intended for bottling milk, an absorption band was found in the spectra, which is responsible for the onset of the destruction process with the formation of aldehyde and carboxylate groups with the formation of aldehyde and carboxylate groups.

Comparison of changes in structure in three different packaging objects containing a polyethylene layer shows the feasibility and necessity of using combined and multilayer materials for food products packaging, in which, even under extreme UV-irradiation, there are practically no photo destruction processes, which is confirmed by spectral researches.

62-70 584

The paper examines the problem of the composition instability in the ready ground spice, turmeric. Analysis of the prevalent methods for turmeric adulteration and substances used for these purposes is given. The visual assessment of color tints of the turmeric root, spices containing it and chemical dyes based on chromium salts is presented. The studies on determination of the lead and chromium content were carried out to study the content of these metals and test the hypothesis of using lead chromate as a dye in adulteration of turmeric. Using the method of electrothermal atomic absorption spectroscopy, it was found that the lead content in the analyzed turmeric samples varied from 1.72 ± 0.58 to 5.03 ± 1.80 mg/kg, while the chromium content was in a range of 5.56 ± 0.85 to 16.15 ± 2.32 mg/kg. As a result of species specific PCR, wheat DNA was revealed in all purchased samples of ground turmeric. The levels of the main raw material replacement were established, which were 0.14% to 14.95% with the correlation coefficient close to 100%; efficiency of the reaction was 1.95, which was 97.5% when expressed as percentage. These levels of an undeclared allergen in the product composition can cause a serious allergic reaction. The authors tested the hypothesis of introduction of sodium and potassium salts for correction of the color spectrum in the ready spice and its correspondence to the natural color within the color spectrum of turmeric. As a result of the complex study of the spice composition, quite high values of chromium were found, presumably not only from the lead chromate compound but also from chromic acid salts, as the high level of potassium that significantly exceeded the native content of this element was found.

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