Ecological study of wine yeast in inoculated vats from La Mancha region

Use of certain selected commercial yeast cultures has become widespread throughout the wine-making sector, but there was not any study about their effectiveness in Castilla-La Mancha region. This study sought to determine, whether the commercial yeast successfully displaced native yeasts during the fermentation process, or whether it was replaced by them. A total of 41 vats containing different grape varieties were sampled at different stages of fermentation, selecting 1640 isolated yeasts, which were characterized using molecular biology techniques (RFLP mtDNA). From results obtained, it can be concluded that inoculation of fermentation tanks with active dry yeasts does not guarantee their implantation during alcoholic fermentation. Indeed, these added strains may be scarce or even non-existent during the process.