Forming the food system of a milk product of mixed fermentation enriched with dihydroquercetin

The purpose of the study was to examine the impact of an antioxidant food ingredient - dihydroquercetin - on biotechnological processes of forming the food system of a sour milk product of mixed fermentation. While developing enriched fermented milk drinks including antioxidant ones, we should take into account that introducing enrichment components in the composition of a product not only increases their nutritional value and provides new functional properties but also ensures the required consumer specifications. In the framework of the study we assessed two technological approaches to enriching a milk product of mixed fermentation with a plant antioxidant: in the first approach a functional food ingredient (lyophilized powder of dihydroquercetin) was introduced in the product system after raw materials preparation before fermentation; in the second approach - after the fermentation process was over before maturing. The effectiveness of the approaches was assessed using titratable and active acidity, microscopy results and total antioxidant activity (DPPH method). The results obtained demonstrated that the modified form of dihydroquercetin regardless of the implemented enrichment approach intensifies the process of fermentation as far as it boosts the development of sour milk microorganisms and increases the value of titratable acidity of the finished product (the growth was 6-15 % in comparison with the reference sample). Besides, the results of microbe activity assessment proved that while using the first technological approach, the dihydroquercetin development of yeast microflora of symbiotic fermentation gets repressed and does not ensure the formation of consumer specifications of a finished product in full. Antioxidant activity of a drink when the food system of a product is enriched with a modified form of dihydroquercetin increases by more than 60 % in comparison with the reference sample, regardless of the implemented technological approach. Thus, the obtained results demonstrated that the production of fermented drinks with antioxidant properties should be accompanied by the introduction of dihydroquercetin-based food ingredient after the fermentation of a product is over.