It was established that decrease of oligochitosans with molecular masses 7.0, 25.4, 45.3 kDa concentration in the process of Lactobacillus bulgaricus cultivation leads to fermented dairy product pH reduction and titratable acidity increase. Further increase in titratable acidity and decrease of lactic acid microorganisms amount was determined during the fermented dairy product storage process. Oligochitosans with molecular masses 7.0, 25.4, 45.3 kDa in concentrations interval from 0.0025 to 0.01 per cent did not exhibit prebiotic properties. Active acidity elevation and titratable acidity depression was observed at the chitosan with molecular mass 350 kDa concentration rises. Also increase of highly molecular chitosan concentration leads to elevation of lactic acid microorganisms total amount, which was more than three degree as many as total count of lactic acid bacteria in control sample.

Enzymatic protein hydrolysates of milk are used as a protein component of functional foods intended for children, athletes, and senior citizens. They are easy to absorb and possess hypoallergenic, antioxidant, antimicrobial, and antimutagenic properties. However, the peptides in their composition have a bitter taste, which limits the use of milk protein hydrolysates in food industry. Functional foods are often fortified with fat-soluble vitamins and other hydrophobic ingredients. They require multicomponent compositions that contain both hydrophilic and hydrophobic compounds. Complexes of β-cyclodextrins with peptides of whey protein hydrolyzates and fat-soluble vitamins can solve this problem. The present research featured nanocomplexes of β-cyclodextrins with whey peptides and their multicomponent mixes with vitamins D3 and A. The methodology involved HPLC-MS, electrophoresis, thermogravimetry, and fluorimetry. The obtained clathrates were used to develop new multicomponent compositions for functional nutrition. The article introduces a new production method for hypoallergenic peptide fractions with a molecular weight of 300–1500 Da from enzymatic whey protein hydrolyzates. The obtained peptides contained 6–14 amino acid residues and demonstrated hypoallergenic properties because they contained no antigenic determinants capable of causing IgE synthesis. The complexes of inclusion contained hydrolyzate peptides of dairy proteins and fat-soluble vitamins A and D3. The research revealed some antioxidant and antimutagenic properties, as well as the toxicological and hygienic profile of the clathrates. The resulting peptide clathrates had a less bitter taste. The inclusion complexes of fat-soluble vitamins D3:β-cyclodextrins, and A:β-cyclodextrins could be converted from an olive oil solution into a soluble powder. 100 g of the multicomponent composite contained 47.0 g of whey protein hydrolyzate of low molecular weight fraction peptides, 1.06 mg of vitamin D3 (42 500 IU), 3.44 mg of vitamin A (10 000 IU), and 1.54 g of olive oil. The article also describes the structural and functional properties of the inclusion complexes. Nanocomplexes of whey protein hydrolyzate of low molecular weight fraction peptides:β-cyclodextrins, D3:β-cyclodextrins, and A:β-cyclodextrins and their multicomponent composite were tested for toxicological and hygienic properties using Tetrahymena pyriformis. They appeared to belong to the 5th hazard class in terms of the average lethal dose (non-hazardous substances). The obtained powder forms of fat-soluble vitamins and peptides are easily dosed and can be used to design new functional foods.

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Adverse environmental conditions are severely limiting the use of microorganisms in food systems, such as probiotic delivery, where low pH causes a rapid decrease in the survival of ingested bacteria, and mixed-culture fermentation, where stepwise changes and/or metabolites of individual microbial groups can hinder overall growth and production. In our study, model probiotic lactic acid bacteria (L. plantarum ATCC 8014, L. rhamnosus GG) and yeasts native to dairy mixed cultures (K. marxianus ZIM 1868) were entrapped in an optimized (cell, alginate and hardening solution concentration, electrostatic working parameters) Ca-alginate system. Encapsulated cultures were examined for short-term survival in the absence of nutrients (lactic acid bacteria) and long-term performance in acidified conditions (yeasts). In particular, the use of encapsulated yeasts in these conditions has not been previously examined. Electrostatic manufacturing allowed for the preparation of well-defined alginate microbeads (180–260 µm diameter), high cell-entrapment (95%) and viability (90%), and uniform distribution of the encapsulated cells throughout the hydrogel matrix. The entrapped L. plantarum maintained improved viabilities during 180 min at pH 2.0 (19% higher when compared to the free culture), whereas, L. rhamnosus appeared to be less robust. The encapsulated K. marxianus exhibited double product yields in lactose- and lactic acid-modified MRS growth media (compared to an unfavorable growth environment for freely suspended cells). Even within a conventional encapsulation system, the pH responsive features of alginate provided superior protection and production of encapsulated yeasts, allowing several applications in lacto-fermented or acidified growth environments, further options for process optimization, and novel carrier design strategies based on inhibitor charge expulsion.

One of the urgent issues of modern food industry is the biological safety. In this regard, especially important for ensuring the safety of functional dairy food for healthy nutrition are new methods developed for the primary sanitation of raw milk, prior to technological processing, in order to reduce the bacteriological contamination and extend the shelf life of the food produced. This is of particular importance for improving the biotechnological properties of milk used in cheese making. The purpose of the work was to develop alternatives to innovative technologies for the heat treatment of raw milk by mild heating that ensures a controlled decrease in its bacterial contamination with a targeted effect on especially dangerous and heat-resistant spore-forming bacteria. Based on biotechnological principles, the theoretical foundations of the bacterial sanitation of dairy raw material prior to technological processing have been studied and developed; the parameters of mild heat treatment that provides a decrease in bacterial contamination by six orders of magnitude, with spores being converted into vegetative forms and subsequently destructed, experimentally and analytically substantiated; the suitability of cheese and other technological properties of raw materials has been increased; the shelf life has been prolonged; and innovative technologies for the production of biologically safe dairy products have been developed. There has been developed a procedure for the heat treatment of low-grade cow’s milk - raw material - for further reservation or use in technological processes in order to improve its microbiological and technological properties and increase the product shelf life. Studies have been performed to inactivate spore-forming bacteria in milk, which has halved their incubation time.