Sherry wine vinegar: physicochemical changes during the acetification process

The quality of a sine vinegar is determined by the raw wine substrate and t he acetification process employed in its production. Attempts to characteri se vinegars have been based on these two features, along with variables suc h as total extract, glycerol, organic acids, volatile compounds and phenoli c composition. When the final products are analysed, it is difficult to eva luate to what extent quality differences are due to the raw material or to differences in production methods, so it is necessary to determine the infl uence of each feature separately. The present work focuses on monitoring ph ysicochemical changes during the acetification of sherry wine by submerged culture. ANOVA showed significant differences for ethanol, acetic and lacti c acids and some volatile compounds (methanol, l-propanol, 2-methyl-1-propa nol, 2-methyl-1-butanol, 3-methyl-1-butanol, acetoin, acetaldehyde, ethyl a cetate and ethyl lactate). However, no statistical changes were found for p henolic compounds during acetification. The phenolic composition of the fin al product was determined by the substrate employed. In addition, the influ ence of cycle duration on the chemical composition was studied; the only co mpound affected by this factor was 2-methyl-1-butanol. (C) 2001 Society of Chemical Industry.