Studying the biochemical transformations in sherry wines subjected to biological aging

Abstract

The fundamental role in the process of biological aging is given to yeast which enrich the wine with substances that contribute to the formation of the characteristic organoleptic properties of sherry. We studied 55 samples of wine in the dynamics of biological aging. The purpose of this research was to study the transformation of wine components during biological aging and to determine their technological value. Generalization of experimental data showed that biological aging determines changes in the composition of wines and physical-chemical characteristics: Reduction of the volume fraction of ethanol, the mass concentration of the components of the acid complex (malic, lactic and acetic acids), amine nitrogen and glycerin as sources of energy and carbon nutrition for yeast. Decrease in the content of phenolic substances, the value of the redox-potential of wine and optical density D420 confirms the protective function of the sherry film that prevents non-enzymatic oxidation of wine components. The biological aging is also characterized by an increase in the mass concentration of aroma-forming substances: Acetaldehyde, diacetyl, acetoin, dioxanes, dioxolans, lactones. Based on the data obtained, the role of the main components of wines in the process of biological aging and the ranges of their variation were determined.