FATTY-ACID COMPOSITION OF LEUCONOSTOC-OENOS, INCIDENCE OF GROWTH-CONDITIONS AND RELATIONSHIP WITH MALOLACTIC EFFICIENCY

Total methyl fatty acids of Leuconostoc oenos were analysed on cell pe llets by gas chromatography. Fatty acid composition varied according t o growth phase: during culture in a semi-synthetic medium, cis-vacceni c acid decreased when lactobacillic acid increased. It also varied acc ording to growth medium: the unsaturated:saturated fatty acid ratio in creased when fatty acids or wine were added to the medium and decrease d in the presence of 10% (v/v) ethanol. On the other hand, the malolac tic efficiency of these L. oenos cultures varied according to growth c onditions. Only cells cultivated in medium to which wine had been adde d were able to achieve malolactic fermentation after direct inoculatio n in red wine. Results concerning both fatty acid composition and malo lactic activity of several strains in different conditions were subjec ted To principal component analysis, in order to detect a possible rel ationship between the fatty acid composition of cells, and their abili ty to achieve malolactic fermentation, but no clear correlation appear ed. Other components of the plasma membrane are also probably involved in the adaptation of L. oenos cells to wine. (C) 1995 Academic Press Limited.