Use of Microbial Cultures in Functional Beverages Technology
Tea is a traditional drink for many nations of the world. In countries of the East, in addition to traditional types of tea, drinks obtained by microbial fermentation of the leaves of a tea plant were used. An example is Chinese tea Hei Cha and a drink obtained by fermenting tea extract - Kombucha. Microbial cultures used for fermentation gave drinks additional functional properties. The purpose of this study was to study the microscopic fungi used in the Hei Cha tea technology and the association of bacteria and yeast from the Kombucha drink, followed by a study of the possibility of their use for producing fermented drinks. Microscopic fungi identified as E. cristatum were isolated from Hei Cha tea samples; Acetobacter bacteria and Saccharomyces yeast were extracted from Kombucha. The effect of the composition of fermented raw materials and cultivation modes on the growth and development of isolated microorganisms was studied. The optimal fermentation parameters were determined and a technological scheme was developed for producing a finished fermented product based on Chamaenerion angustifolium (narrow-leaved fireweed). It was shown that the microorganisms used do not synthesize mycotoxins, are capable of synthesizing antioxidants and B vitamins and others. In drinks obtained by fermentation of leaf extracts of Camellia sinensis (Chinese camellia), Chamaenerion angustifolium (narrow-leaved fireweed), the content and composition of biogenic amines, amino acids phenolic compounds and antioxidants. A beverage formulation was developed using isolated microbial cultures, which include honey, malt wort, grape juice, mate, and coffee as additional ingredients. Product safety has been confirmed by microbiological analysis. The resulting drinks have a rich color, a pleasant aroma, a sweet and sour taste with fruit tones.