Fatty acid profiling: a feasible typing system to trace yeast contamination in wine bottling plants

The long-chain fatty acid composition of yeast strains was determined for several species associated with the wine industry. The Saccharomyces cerevisiae, Zygosaccharomyces bailii, Saccharomycodes ludwigii, Schizosaccharomyces pombe, Brettanomyces/Dekkera spp. , Pichia anomala, Pichia membranaefaciens and Lodderomyces elongisporus species presented distinct fatty acid profiles after multivariate statistical analysis. The Zygosaccharomyces rouxii species showed profiles similar to Zygosaccharomyces bailii. The use of fatty acid profiling in wine bottling plants and wines makes it possible to trace the origin of the strains responsible for spoiling the final product. In one case the origin was found at the outlet of the finishing filter and identified as Zygosaccharomyces bailii. In the other case the source of contamination was discovered in the heads of the filling machine and assigned to the Pichia membranaefaciens species. The results point out the discriminating power and the industrial applicability of the technique described in this work to analyse yeast long-chain fatty acid compositions.