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Vol 2, No 4 (2019)
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4-9 714

NMR-spectroscopy was used for development of the criteria which characterize the chilled and frozen fish quality. It has been shown that 1H-NMR experiments can be used as quality factor to measure the concentration of inosine, hypoxanthine and inosine-5’-monophosphate generated during the fish storage. The quality factor is expressed by the K1 correlates well with the sensory quality of chilled Atlantic salmon (Salmo Salar), whereas, quality factor H is more sensitive for measuring the quality characteristics of frozen pink salmon (Oncorhynchus gorbuscha), chum salmon (Oncorhynchus keta), sockeye salmon (Oncorhynchus nerka).

10-13 575

In the Russia beverage market, functional beverages are increasingly popular with the population due to their intensive lifestyle and worsening environmental situation. Of great importance is the shelf life of drinks, since they determine the presence in the composition of useful nutrients that affect the various systems of functioning of the human body. The main groups of functional compounds are given. Ways to increase the shelf life of beverages, all aspects and their impact on the safety of the functional components of beverages are considered. The role of flavonoids as one of the groups of functional compounds has been evaluated. Recent studies on the effect of certain functional compounds on each other are given.

14-17 866

The scope of the project consisted in research-based development of new complex food additives from lactic acid and its derivatives for enhancing microbiological safety and shelf life extension of healthy food products. The object of research included: trial samples of complex food additives from lactic acids and its derivatives. The samples were obtained chemically using the following basic components: food grade lactic acid with 79.6% base substance mass fraction; acetic acid with 99.8% base substance mass fraction; propionic acid with 99.6% base substance mass fraction; neutralizing agents for synthesis of salts of the acids used, and propylene glycol with 99.8% base substance mass fraction. The optimal balance of the ingredients in the formula of the additive delivers the optimal level of true acidity combined with antimicrobial and antioxidant effect, and enhances organoleptical performance and process parameters of food products. This complex food additive containing lactate and acetate features high counter-regulatory effect on testing cultures of pathogenic organisms of rope spoilage of wheat bread and can be used for production of non-perishable products. The use of complex food additive in the production of dressed fish preserves activates biochemical processes related to fish maturation and delivers improved product quality and extended shelf life.

18-24 551

A method has been developed for the production of organic ingredients from secondary products resulting from the high-quality grinding of triticale and wheat into flour, which involves the enzymatic action of amylolytic enzymes to release starch polysaccharides while preserving the native properties of dietary fibers and biologically active substances associated with them. To a large extent, the features of the properties of the obtained ingredients are due to the number and composition of the components of dietary fiber of grain, as well as the morphological features of their structure. It is shown that the viscosity of aqueous colloidal systems at a concentration of soluble dietary fiber of the ingredient 0.5 % increases 11 times; at a concentration of 1.0 %   — 30 times, forming a viscous gel-like structure. This allows them to be used for gelling, thickening and stabilization of aquatic food systems. The use of ingredients with a high content of NLP in baking is possible only taking into account their water absorption capacity. A method for the enzymatic modification of secondary products of processing of grain triticale was developed. On the basis of the study of the kinetics and efficiency of the effect of proteolytic and cellulolytic enzyme preparations (EP) and their compositions, optimal conditions for enzymatic modification (the EP dosage is 0.5…0.75 units of PA/g of bran, 0.3…0.4 units of CA/g of bran, the optimum temperature is 40–50 °С, pH is 5.0 and 3.5, the duration of reactions is 1.5 hours) have been determined. The use of cellulolytic EP allowed to increase the amount of reducing substances and soluble protein by 1.5–2.5 times in comparison with the control sample. The biomodified bran obtained using the MEC «Shearzyme 500 L» + «Neutrase 1.5 MG» and «Viscoferm L» + «Distizym Protacid Extra» has a high degree of hydrolysis of non-starch polysaccharides and proteins, is characterized by a certain ratio of high-, medium-, low-molecular peptides and amino acids, has different functional and technological properties. They can be used in the production of a wide range of general-purpose, functional and treatmentand-prophylactic food products.

25-30 547

A complex of technical solutions is presented which makes it possible to study the influence of external factors on changes in the indicator of fat acidity value (FAV) and a range of other parameters characterizing the quality of preservation of long-term stored wheat grains in South Russia. Storage conditions (natural climatic, model) and also the effect of dust suppression treatment of grain by oil glazing that is carried out in some grain terminals in the South of Russia were taken as controlled external factors. New data has been obtained on changes in parameters of food suitability of the wheat grains during storage under model conditions with varying degrees of severity of climatic conditions in South Russia. After 6 months of storage the most considerable changes in FAV value were found for 4th class of wheat stored in natural climatic conditions with intensive insolation, the increase was 1.7 mg KOH/1 g of fat (from 7.3 mg KOH/1 g of fat up to 9.0 mg KOH/ 1g of fat). Minimum changes in the same parameter for the same storage period were observed for the wheat of the 3rd class stored in a thermostat at a stable high temperature of 35 ºС (from 11.6 mg KOH/1 g of fat to 11.5 mg KOH/1 g of fat). For wheat of the 4th class, the changes were 0.7 mg KOH/1 g of fat (from 7.8 mg KOH/1 g fat to 8.5 mg KOH/1 g of fat). Analyzes of stored wheat grains subjected to dust suppression by the oil glazing showed similar results, which allows us to state the absence of a significant effect of oil glazing on changes in wheat properties during its storage.

Based on the results of the experimental analysis and a generalization of the data obtained an assumption was made on the possible reasons for the lack of pronounced trends in the data for the expected increase of FAV value in food suitability of the wheat grain when it is stored under typical model conditions of South Russia. The likely reason for this is the corresponding moisture state of grain, the water activity of grain was about 0.45. Such a low value was due, in particular, to the fact that samples of model-stored grain had a limited volume and do not reproduce the mass transfer processes that involve deep layers of the grain mass (because of the mass absence), which takes place during storage of grain in an industrial environment. The tools were proposed for the operational monitoring of the moisture state of wheat grain during storage. Moreover, a plan has been developed to expand the field of modelling storage processes in terms of varying the moisture state of the stored wheat grain samples with an assessment of the influence of moisture state on the dynamics of changes in the parameters to be controlled.

31-33 590

The presence of food additives in food products may be associated with the risk of their toxic effects on human body. Therefore, the study of approaches to testing their safety seems to be a particularly urgent task. The aim of this study was to determine the conditions for extracting food preservatives from the samples of preserved pureed vegetables for further bioassay of the extract obtained in the Allium test. Onion roots were used as a test object in this method. Two extraction methods of benzoic and sorbic acids added to pureed vegetables have been developed. Distilled water and acetone were used as extracting solutions. The extraction efficiency was evaluated on Shimadzu Prominence LC-20 liquid chromatograph (Japan) in the ultraviolet range, wavelength 235 nm (benzoic acid), 285 nm (sorbic acid). According to the results of studies using both water and acetone as extractants, the degree of preservatives extraction was approximately the same and quite high. In the quantitative calculation of the preservatives content in pureed vegetables, the value of the correction factor was 0.8. However, due to certain production characteristics of this product, i. e. the stage of cauliflower homogenization, obtaining an extract with acetone seems to be more acceptable for the Allium test conditions.

34-37 955

The article shows that the studied samples of raw milk in terms of composition (mass fraction of fat, protein, lactose and milk solids-not-fat) met the criteria of suitability for cheese, and its physic-chemical properties (titratable acidity, density, freezing point) were within acceptable limits. Moreover, rennet sample corresponded to the first and second classes. It was proved that the number of spores of lactating fermenting microorganisms met the requirements for milk for the production of any kind of cheese. It was established that the fatty acid composition of raw cow’s milk used to produce cheeses at various enterprises varied significantly. The data indicate the variability of the content of all groups of fatty acids — low molecular weight, saturated, monounsaturated and polyunsaturated. As a result of gas chromatography studies using the chromatographic complex «Chromos GX-1000» with a flame ionization detector and a CP 88 quartz capillary column — Sil 88 for FAME100 m × 0.25 mm × 0.2 µm, it was found that the largest absolute fluctuations were for saturated (± 7.03 % of the average value) and monounsaturated fatty acids (± 3.77 % of the average value). Absolute fluctuations in the group of low molecular weight fatty acids amounted to ± 2.62 %, and in the group of polyunsaturated — ± 1.02 % of the average value. The calculation of the relative deviation showed that the most varied groups were the ones of low molecular weight fatty acids (± 28.40 rel.%) and polyunsaturated fatty acids (± 25.11 rel.%). At the same time, a relatively high content of certain fatty acids: myristoleic, palmitic, palmitoleic and low levels of stearic and oleic fatty acids, was revealed in individual milk samples.

38-41 557

The formation of food liquid medium structures containing at least 70 % of disperse particles with high dispersiveness has been considered. The possible formation mechanisms of food liquid medium structure when slow (hydrodynamic) and quick (acoustic) processes create favorable conditions for cavitation have been studied. The possibility to control these processes for initiation of mechanical and kinetic reactions that change the structure of the medium has been demonstrated. The invert syrup has been selected as the study object. The change in the invert syrup structure before and after such cavitation treatment has been recorded with the use of metallographic microscope Nikon Eclipse MA100. The decrease in disperse phase sizes from 2–3 µm to 0.1–0.4 µm along with establishing the high uniformity of component distribution as compared to the syrup without cavitation process treatment has been detected. 

42-47 634

The results of the study on changes in the composition and quantity of epiphytic and endophytic microorganisms of plant products during storage and transportation are presented. For the investigation, the authors took apple fruits and leafy spicy green products that had biological peculiarities and allowed investigating processes of the long-term and short-term main stages (cold storage, transportation by refrigerated transport, presales storage) of the continuous cold chain on the way to a consumer. Apple fruits were placed in storage in cold chambers with the temperature regimes of plus (2–3)°C and minus (1–2)°C, where they were stored for 90 days. The vegetative organs of dill and parsley were transported during 8 hours by a refrigerated truck and placed in the commercial refrigeration equipment at two temperature regimes (4–5) C and (0–1) C for 72 hours for presales storage. The results of the microbiological analysis showed that the number of endophytic microorganisms (bacteria, yeasts and molds) was lower by 1–3 orders of magnitude in apple fruits and by 2–3 times in green vegetables compared to the number of epiphytic microorganisms. It was established that the regime of storage at negative temperatures completely inhibited the development of epiphytic bacteria on fruits, significantly delayed the multiplication of epiphytic yeasts and molds; while at a positive temperature the number of bacteria increased approximately by 10–17 times, yeasts by 180 times and molds by 3 times. The dynamics of changes in the number of endophytic microorganisms during storage showed the same trend that was observed for epiphytic microorganisms. Analysis of the microbial quantity after transportation of green products showed an increase in abundance of the revealed groups of epiphytes and endophytes by 1.5–3 times upon absolute prevalence of bacteria. After short-term storage, a significant growth of the revealed microbial groups was found; with that, their quantity was 1.5–6.5 times higher at (4–5) C than at (0–1) C. The authors experimentally confirmed the conclusion that with respect to reduction of losses due to microbiological spoilage and extension of shelf life, the cold storage regime of the studied plant products at near-zero temperatures is preferable compared to the regimes of storage at higher positive temperatures.

48-52 671

High-sugar canned fruits, such as jam, marmalade, confiture, are characterized by a high content of soluble dry solids and high acidity, which allows to apply to them pasteurization processes as heat treatment. In comparison with sterilization processes, heat treatment of hermetically sealed canned food during pasteurization is implemented at temperatures less than 100°C.

The article presents the results of the development of scientifically-based pasteurization modes for high-sugar canned food for industrial continuous-acting pasteurizers (CAP — continuous-acting pasteurizers) of open type with a temperature in the heating area less than 100°C. For today, such pasteurizers are widely spread due to the simplicity of their design, high productivity, with the option to reduce consumption of water, steam, electricity and to use it for the various types of packaging. So, the actual task of this article is the establishment of canned fruit pasteurization modes for such pasteurizers.

The development of pasteurization modes for high-sugar canned food using strawberry jam as a sample was carried out in the experimental equipment simulating the operation of a continuous-acting pasteurizer. The studies were implemented to confirm that the developed modes of heat treatment in the CAP as a matter of fact provide industrial sterility of the produced high-sugar canned food. Optimal pasteurization modes have the following parameters: heat treatment in an autoclave sterilizer at a heating temperature of the heating medium 97°C and stage-by-stage cooling of the products with water at temperatures 70°C, 50°C and 30°C.

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