PICHIA KUDRIAVZEVII IN MIXED CULTURES: AN ALTERNATIVE FOR MALOLACTIC FERMENTATION IN BIOLOGICAL WINE DEACIDIFICATION?

CURILEN, Y.; CARREÑO, V.; CAMACHO, E.; OTEIZA, J. M.; CABALLERO, A. C.; DEL MÓNACO S. M.

Bariloche

Simposio; 34 INTERNATIONAL SPECIALIZED SYMPOSIUM ON YEASTS; 2018

IPATEC-CONICET

Introduction. In the Comahue Region, placed in the Argentinian north Patagonia 40º SL, grape musts present high malic acid contents (3 to 6 g/L). While Malolactic Fermentation (MLF) is a routine practice for wine deacidification, it is a process difficult to control at the industrial scale. Therefore, the aim of this study was to evaluate the competence of a native Pichia kudriavzevii/Saccharomyces cerevisiae mixed culture for L(-)Malic acid consumption during Alcoholic Fermentation (AF). P. kudriavzevii proved its ability to metabolize this substrate as the only carbon source, reason why we proposed it for wine deacidification.Materials and method. Wine vinifications were carried out with Malbec musts at a pilot scale (200L) during 2015 to 2017 vintages. Wines were elaborated with conducted AFS either with a native S. cerevisiae starter (ScF8) or with ScF8 and P. kudriavzevii simultaneous mixed starter (1/100 ratio) (CoC). Young wines were sulphited to inhibit MLF. Physicochemical and aromatic quality was determined once bottled, by means of conventional (INV) and chromatographic (HPLC y GC-FID) methods. Sensorial quality was evaluated by qualitative assays and trained panel tasting, and subjected to consumer preference polls. Results. All the obtained wines were considered normal, dry and qualified as very good in the tasting, but the CoC presented significantly lesser malic acid content and higher esters content than ScF8 wines. Sensorial analysis evidenced statistical differences between CoC and ScF8 products, with a fruitier aroma and consumer preference for CoC wine.Conclusion. CoC validation in real environment for three consecutive years presents this mixed starter as an alternative for FML in Patagonian wine deacidification.