Prevalence and biodiversity of Brettanomyces bruxellensis in wine from the north-west of Italy

Brettanomyces bruxellensis catalyses the transformation of hydroxycinnamic acid, a compound naturally occurring in grapes, producing volatile phenols thus reducing the organoleptic quality of wine. Volatile phenols can confer off-odours, in a concentration dependent way, described as phenolic, animal, mousy, wet wool, medicinal, smoky and spicy. In this paper we describe a multi disciplinary approach for the investigation of B. bruxellensis presence in some Italian wines. For the detection and quantification of B. bruxellensis in 87 different wines, we have applied culture independent and dependent method (quantitative PCR and traditional microbiological analysis). Moreover, Headspace Solid-Phase Microextraction method was used to quantify ethyl and vinyl phenols in wines. Statistical analysis performed on the results obtained showed that there was no correlation between culture-dependent and culture-independent methods. Strain biodiversity was investigated by SAU-PCR and a differentiation of the isolates based on the geographical origin was highlighted.