Technological application of autochthonous Meyerozyma guilliermndii cultures in Chardonnay

Using Chardonnay grape, the fermentation characteristics of sequential inoculation with M. guilliermondii and S. cerevisiae in the pilot fermentation process of dry white wine were examined. In this study, the physical and chemical indexes, color indexes, volatile aroma compound composition, and sensory indexes of 2 tons of samples at the end of alcoholic fermentation (AF) and malolactic fermentation (MLF) were analyzed. The results showed that the M. guilliermondii biomass in the treatment group (inoculated M. guilliermondii and S. cerevisiae sequentially) was always higher than 10⁶ CFU/mL during AF, and the basic physicochemical indexes of samples met the requirements of the national standard GB/T15038-2006 (Wine). Also M. guilliermondii NM218 can significantly increase the color saturation of Chardonnay white wine. Regarding aromatic characteristics, the total alcohol, ester, and terpene contents of wine samples after mixed fermentation were higher than those of control group (only inoculated S. cerevisiae). Compared with control wine samples (only with S. cerevisiae), the treatment group had significantly increased ethyl caprylate, ethyl nonanoate, phenethyl acetate, and ethyl laurate contents, including n-heptanol, which can provide Chardonnay dry white wine a richer fruity fragrance. meanwhile, the sensory scores of wine samples were higher in the treatment group. In conclusion, mixed fermentation could boost the aroma quality and sensory pleasure of dry white wine, with the potential for industrial application.