Abstract
Wine and cider vinegars were experimentally manufactured from commercial grape and apple juices, and differences in fatty acid components were analyzed among fermentation stages. Following alcoholic fermentation of Bailey A (a grape variety for red wine) juice, the increase in the proportions of palmitic and stearic acids was found to be accompanied by relative decreases in those of linoleic and linolenic acids. Reversed phase HPLC analysis showed a notable increase in a peak corresponding to oleic acid during acetic acid fermentation, although changes in fatty acid components were slight compared with those during alcoholic fermentation. In the case of Koshu (a grape variety for white wine), no significant difference was observed in fatty acid composition between the juice and its fermenting liquid (wine). However, after acetic acid fermentation, the vinegar produced had a fatty acid composition that was qualitatively and quantitatively similar to that of Bailey A. During alcoholic fermentation of apple (Delicious variety) juice, an increase in oleic acid and a decrease in linoleic acid were observed, followed by increases in palmitic and stearic acids after acetic acid fermentation, similar to changes observed during wine vinegar manufacturing. Thus, we found that juices with characteristic fatty acids produce vinegars with roughly corresponding compositions. Moreover, capillary-GC analysis of fatty acid methyl esters showed that cis-vaccenic acid (an oleic acid isomer) originating from acetic acid bacteria can be transferred into vinegars made by the acetic acid fermentation process. cis-Vaccenic acid was also detected in ten varieties of commercial wine and cider vinegars with cis-vaccenic acid/(oleic and cis-vaccenic acids) ratios of 0.07-0.59.
