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  • Документ
    THE EFFECT OF THE INTENSITY OF AERATING THE MEDIUM ON THE METABOLIC ACTIVITY OF ALCOHOL YEAST
    (2019) L. Levandovsky, М. Kravchenko
    The article presents the results of investigating how the intensity of aerating the medium effects on the cultivation process and the metabolic activity of alcoholic yeast Saccharomyces cerevisiae, strain U-563, in the modern technology of alcohol and baking yeast from molasses. The chemical and technological parameters of media at the aerobic and anaerobic stages of the process, the level of accumulation of the major and secondary products of yeast metabolism, and their enzymatic activity have been determined by methods commonly employed in science and in the practice of alcohol biotechnology. The objects of research were the yeast Saccharomyces cerevisiae, molasses wort, the medium in the process of yeast cultivation, and fermented wash. It has been established that two factors are the most important in the accumulation of alcoholic yeast biomass: the intensity of aerating the medium, and the staged introduction of the substrate during biomass cultivation. The more aerated the medium, the more intensively secondary metabolites of yeast Saccharomyces cerevisiae are formed (glycerol, aldehydes, higher alcohols, volatile acids, and esters) – both at the yeast generation stage and during anaerobic fermentation. When yeast Saccharomyces cerevisiae is grown in a gradient-continuous manner in a battery of series-connected apparatuses, with undiluted substrate (molasses) added by degrees, yeast biosynthesis is significantly enhanced compared to the traditional homogeneous-continuous method. The results obtained indicate the active metabolism of carbohydrates in the Krebs cycle, when the medium is intensively aerated. Besides, the results reveal the high reactivity of aldehydes and esters that results in their transformation into other compounds, and in a great decrease in their amount at the anaerobic stage of the process. However, a progressive increase is observed in glycerol, higher alcohols, and volatile acids, starting from the first yeast generator and up to the last fermentation apparatus, irrespective of the level of aerating the medium during yeast cultivation. These findings can be effectively used to manufacture food, technical, and fuel ethanol industrially from sugar-based raw materials in the course of co-production of alcohol and baking yeast.
  • Документ
    KINETICS AND ENERGY OF POULTRY MEAT DEHYDRATION IN VACUUM AND MICROWAVE FIELD CONDITIONS
    (2019) O. Burdo, N. Povarova, L. Melnyk
    The article presents the results of obtaining dried poultry meat under vacuum conditions using ultrahigh electromagnetic energy sources. A characteristic of the most common principles of drying is presented, which shows that the trends in the technology of drying technology is a reduction of specific energy consumption. From literary sources it is known that this is the best way to preserve meat protein in the native state. This method of drying leads to the release of a large amount of heat, resulting in evaporation can occur at a low temperature. The heat dissipated is spent exclusively on the evaporation of moisture without heating the fabric of the product. The rational modes of microwave-vacuum drying for meat semifinished products are determined. Drying was carried out at a temperature below 40°C and a pressure of 8 kPa with simultaneous processing by an electromagnetic field at a frequency of 2.7 GHz. This contributes to the intensive evaporation of moisture without a significant change in the structure of the surface layer, reducing the length of processing. Microwave-vacuum drying provides high functional and technological properties, namely: moisture-binding ability, water-retaining, fat-retaining ability and mass fraction of residual moisture, and better organoleptic characteristics. According to the sensory evaluation, the samples studied had a more fragile consistency, characterized by dry powders, a pleasant taste and a flavor similar to boiled chicken meat. The article shows the dependence of the mass of condensate on the duration of drying. On the basis of what was determined the duration of drying of the meat additive, which is 3 hours, while the mass fraction of residual moisture is 4.5%. It was established that obtaining dried meat semis from poultry meat under vacuum conditions using ultra high frequency electromagnetic energy sources allows to receive products with less energy and for a shorter period of production.
  • Документ
    OBTAINING AND CHARACTERISTICS OF A PAPAIN AND MAIZE ARABINOXYLAN COMPLEX
    (2019) N. Cherno, S. Ozolina, T. Bytka
    The Ukrainian people’s diet lacks a number of biologically active substances. But their addition to the food is not effective enough as aggressive bodily fluids influence their activity and substantially reduce it. There are undesirable changes in the properties of biologically active substances during their storage, too. That is why it is so urgent a task to increase the effectiveness of biologically active substances by compounding them with polysaccharides in order to protect them from the unfriendly environment. It has been considered how practical it is to form a complex of papain and maize germs arabinoxylan to modify the properties of the enzyme in the intended direction. It has been proved that the complex formation taking place when biopolymer solutions are combined results in the enzyme activity increase. A number of factors (the concentrations of biopolymers solutions, their volumetric ratios, the duration of the contact, pH medium) influencing the enzyme activity in the complex have been studied. The rational conditions have been determined under which a complex can be obtained far more active than the original papain. These conditions are: a 0.25 % polysaccharide solution mixed with a 4.0 % enzyme solution, with the volumetric ratio being 1:1 and pH 6, at room temperature, for 20 minutes. Introducing papain into the complex makes it more resistant to pH and temperature changes. For the physiological pH values ranging 2 to 8, the enzyme activity in the complex composition is higher than free papain. Complex formation increases the enzyme resistance to higher temperatures, especially in the first 90 minutes. Obtaining of the complex is proved by thermogravimetric analysis.
  • Документ
    STUDY OF THE BIOTECHNOLOGICAL POTENTIAL OF SELECTED LACTIC ACID BACTERIA CULTURES
    (2019) N. Kigel, I. Melnik, O. Naumenko
    Fermenting microflora has been selected by biotechnological activity markers, with various methodological approaches used, namely: directional selection, selection of bacteriophage-insensitive mutants, protoplast regeneration. The experimental data show a significant biotechnological potential of the selected lactic acid bacteria. They are characterized by high milk-clotting activity and yield, the ability to form aromatic compounds and/or viscous components, excellent organoleptic qualities of clots fermented by them, antago-nistic activity against pathogenic and opportunistic pathogenic microorganisms, and phage-resistance to species-specific virulent phages. The collection of industrial microorganisms of Institute of Food Resources of National Academy of Agrarian Sciences (IFR NAAS) has been supplemented with new bioactive strains, in particular, the species Streptococcus thermophilus, Lactobacillus acidophilus, Lactoba-cillus rhamnosus and Lactococcus lactis. Four bacterial compositions have been created. Three of them (Iprovit-LB-R; Iprovit-LB-A, and Iprovit-ST) are supposed to be used as functional enrichers for dry foodstuffs or as biologically active supplements. The bacterial prepara-tion Iprovit-Bifidolux is a universal composition. It can be introduced both as a fermenting culture for milk fermentation and as an enricher for dry and liquid foodstuffs. Biotechnologies for the production of dry bacterial preparations on the basis of selected strains have been field-proven at the State Research Enterprise of Starter Cultures that belongs to the IFR NAAS. The data on a wide range of clinical and therapeutic effects of the bacterial preparation Iprovit-Bifidolux allow recommending it for manufacturing functional foods.
  • Документ
    PERSPECTIVES OF THE USE OF PLANT RAW MATERIAL EXTRACTS FOR STORAGE OF TOMATOES
    (2019) A. Dubinina, T. Letuta, T. Frolova, H. Seliutina, O. Hapontseva
    The paper presents the overview data of the diseases and major classes of microorganisms which cause tomato damage after harvesting. Generally accepted effective ways of storage of fruit and vegetable products are considered. These are cold storage and storage in the altered gas environment – regulated and modified (RGE and MGE). It is shown that technologies of storage of fruit and vegetable products with the use of film-forming substances are widely used abroad, and recently they have also been developed in Ukraine. In recent years, prior to the storage, fruits and vegetables have been processed with preparations which have protective properties, and also with antioxidants. Antioxidant compositions on the base of aqueous solutions of santochin, aminophenol, ionol, sorbic and benzoic acids are introduced in the field of fruit and vegetable products storage. There are no studies about the choice of film-forming compositions and antioxidant preparations which take into account the effect of specific microflora of individual fruits and vegetables, as well as the features of their chemical composition and physiological structure. Bacteria and fungi are the two main classes of microorganisms which cause tomatoes damage after harvesting. All diseases have certain manifestations, by which they are identified, and the characteristics of each disease agent, peculiarities of how it spreads and affects fruits are also very specific. Literature analysis has shown that the composition of extracts of ginger, orange peel and garlic bulbs can be an effective universal protection preparation during storage, which covers the whole spectrum of typical tomato diseases. Since the high water-solubility and safety are important characteristics of substances that have direct contact with food products, it is recommended to use aqueous and hydroglyceric alcoholic extracts of plant raw materials when developing the technology of preparation. Further microbiological and toxicological studies of the test samples are needed for determining of working concentrations of extracts and selection of an effective composition.