EFFECT OF YEAST BIOSORBENTS ON WINE QUALITY
Foreign food industries know a variety of products derived from wine yeast cells. These products are used to improve the sensory properties of wine. This article describes the effect of a new yeast biosorbent on the sensory and physicochemical properties of white and red wine, e.g., their sorption capacity for heavy metals. The research featured red and white wines treated with the novel biosorbent. Glutarom (France) served as control. The study relied on various physicochemical, organoleptic, biochemical, and microbiological methods. The biosorbent affected neither the volume fraction of ethyl alcohol nor the mass concentration of sugars and titrated acids. However, the biosorbent reduced the mass concentration of volatile acids in terms of acetic acid: it decreased by 20% in the white wines and by 50% in the red wine samples. The mass concentration of the reduced extract decreased by 0.2-0.7 g/dm3 as the amount of sorbent increased. In the white wine samples, the protein concentration decreased by 1.5-1.8 times, while the concentration of polysaccharides decreased by 110-115 mg/dm3. The content of phenolic compounds decreased by 13-37%, depending on the amount of the sorbent, due to their condensed forms. The biosorbent reduced the value of the redox potential. The yeast sorbents effectively adsorbed metal cations, including those of heavy metals. A set of experiments also revealed the difference in sorption time for different metal cations. The effectiveness of the biosorbent was dose-dependent. The wines treated with the biosorbent had better sensory assessment results, especially the red wine samples. They had a soft, round, and harmonious flavor and a bright aroma with pronounced varietal tones. The novel biosorbent proved to have a good sorption capacity for phenolic compounds, as well as cations of toxic metals. It improved the sensory profile of the red and white wines. This biosorbent can substitute their imported analogs in the Russian wine industry.