The sugar fermentation activity of lactic acid bacteria plays a significant part in the production of plant-based fermented foods. Lactic acid bacteria are demanding on nutrients in the medium. They generate energy only during the breakdown of carbohydrates. Lactic acid bacteria do not ferment polysaccharides like starch ordextrinsbecause they lack the necessary hydrolytic enzymes. Lactose is absent in plants, but this sugar is important for the growth of lactic acid bacteria. Due to the increased demand for the alternative fermented dairy products, it is necessary to know the ability of starter culturesto ferment various carbohydrates. The results of a study of the sugar fermenting activity of bacterial cultures, including the species S.thermophilus, L. delbruckii ssp. bulgaricus, L. lactis ssp. lactis, L. lactis ssp. cremoris, L. lactis ssp. lactis biovar diacetylactis, Leu. mesenteroides ssp. cremoris, and Leu. mesenteroides ssp. mesenteroidesare presented.Cultures with S.thermophilusand L. delbruckii ssp. bulgaricus show the lowest growth rates on maltose medium. Cultures with Leu. Mesenteroides rapidly ferment sucrose rapidly. Cultures withL. lactis ssp. lactis, L. lactis ssp. cremoris, and L. lactis ssp. lactis biovar diacetylactis rapidly metabolize maltose, sucrose, and lactose. All lactic acid bacteria rapidly utilize glucose.

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We carried out cultivation of Chlorella sorokiniana microalga using various irradiation sources: daylight lamp with spectral range 530-610 nm and filament lamp with spectral range 3.5-5.0 μm. Specific growth rates were evaluated for these conditions at exponential phase. From the obtained biomass we extracted lipids and determined its’ fatty-acid content. Also we analyzed triacylglycerol (TAG) content and unsaturated fatty acids, as well as oleinic acid content. Biomass irradiation by infrared source causes enlarging of total lipid content in alga biomass, as well as saturated fatty acids and oleinic acid portions. It is viable to use infrared irradiation mode for accumulation of non-polar lipids (TAG) at stationary growth phase, which might be used for biofuel obtaining after fractionating. Polar lipid fraction, extracted from biomass at linear growth stage, might be used for obtaining essential polyunsaturated fatty acids.

At preservation of fruits and berries mass-exchange processes take place in liquid mediums, which define quality of the canned production. The composition of covering syrup should guarantee preservation of turgor, taste and color of fruits and berries and prevent fermentation processes. We carried out construction and adequacy examination of kinetic model for moisture osmotic transfer for fruit-berry material to covering syrups at thermal and refrigerating preservation. We obtained empirical coefficients. It was established that moisture migration rate depends on berry type and syrup concentration. Moisture loss for more than 30% results in berries turgor loss, which makes its further storage impractical. Using the obtained equation and empirical constants, we have established that the duration of the refrigeration storage of cowberry canned in 30% sugar syrups for the stated conditions was about 130 days.

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