Diversity of Saccharomyces cerevisiae in patagonian wine fermentations: implicances in the implantation of a regional starter

LOPES, C.A.; LAVALLE, L.; ZAJONSKOSVKY, I.; SANGORRÍN, M.P; GIRAUDO, M.R:; CABALLERO, A.C.

Tucuman

Simposio; Simposio internacional de Biotecnologia. Aplicación en alimentos, salud y medio ambiente.; 2004

SIB

In this work, the diversity of S. cerevisiae strains associated to wine fermentationswas characterized. These fermentations were carried out in two cellars located indifferent areas from North-Patagonia with particular enological characteristics. Therelationship between native S. cerevisiae diversity and the dominance of the nativestarter S. cerevisiae MMf9, was also studied. Diversity of S.cerevisiae wascharacterized by both mtDNA-RFLP analysis and killer biotype methods. Therelatedness among native strains using these methods was evaluated throughPrincipal Coordinate Analysis (PCoA).A great diversity of indigenous north-patagonian S. cerevisie strains wascharacterized. This diversity was higher by using mtDNA-RFLP than killer biotypemethods, then the former was chosen to population dynamic analysis. In spontaneousfermentations a sequential substitution of S. cerevisiae strains throughout fermentationwas observed and in guided fermentation the S. cerevisiae MMf9 starter showed ahigher dominance in HC (90%) than in RC (60%) fermentations. A high similaritybetween MMf9 starter and S. cerevisiae strains associated with HC cellar wasevidenced using mtDNA-RFLP analysis. The MMf9 strain, genetically more relatedwith strains from HC area, would be better adapted to ecological features of this area.Additionally, two native S. cerevisiae populations corresponding to differentgeographical-ecological origin, were observed by using both typing methods.Keywords: killer yeasts, mtDNA-RFLP, genetic diversity