Enhancing the tolerance of the Starmerella bacillaris wine strain to dehydration stress

Abstract

A protocol was developed to obtain Starmerella bacillaris as an active dry wine yeast (ADWY), which will facilitate winemakers to realize sequential inoculations of grape must to improve wine complexity. In the present study, several compound solutions were analyzed during the dehydration–rehydration process for Starmerella bacillaris strains isolated from related environments of alcoholic beverages. The ADWY obtained from Starmerella bacillaris were evaluated in fermentations at laboratory scale, obtained by sequential- and co-inoculation with Saccharomyces cerevisiae; the fermentative and aromatic parameters were evaluated and discussed. Our results for one Starmerella bacillaris strain show that the enhancement of viability might lead to a 4-fold higher survival rate when cells are dried in the presence of 10% trehalose, followed by rehydration in 0.5% galactose solution. In co- and sequentially inoculated grape must fermentations with Saccharomyces cerevisiae, the laboratory-scale wines obtained with Starmerella bacillaris ADWY did not show major changes in terms of the main volatile compounds, but there was an improvement in the fermentation performance behavior. The present study paves the way to develop a protocol for developing Starmerella bacillaris as an ADWY.