Abstract:
To clarify the potential of nitrogen source management and inoculation strategies for improving the flavor quality of wine fermented by a mixture of
Starmerella bacillaris (
S. bacillaris) and
Saccharomyces cerevisiae (
S. cerevisiae) , this study evaluated the effects of two levels of assimilable nitrogen (160 and 300 mg/L) and three inoculation methods (pure, simultaneous, and sequential inoculations of
S. bacillaris and
S. cerevisiaeon) on wine fermentation kinetics, physicochemical parameters, volatile composition, and sensory characteristics. Results showed that nitrogen source supplementation can significantly promote the sugar metabolism and fermentation process of yeast, and increase the total amount of volatile compounds by 3.23% to 35.98% (
P<0.05), with notable increases in higher alcohols and acetates. Different inoculation methods affect the glycerol content, composition of aroma compounds, and sensory expression of wine.
S. bacillaris significantly increased the glycerol content, reaching 11.47~18.63 g/L (
P<0.05), enhancing the sweetness and fullness of the wine. Principal component analysis reveals that different inoculation strategies exhibit distinct aroma characteristics. Both
S. cerevisiae pure culture and simultaneous inoculations are dominated by isoamyl acetate and ethyl decanoate, enhancing the fruity aroma of wine. Both
S. bacillaris pure culture and sequential inoculations are dominated by phenylethyl alcohol, ethyl acetate and isobutanol, imparting floral and mellow aromas to wine. There is a significant synergistic effect between the supplementation of nitrogen sources and the sequential inoculation strategy. The sequential fermentation of the nitrogen-supplemented group was particularly outstanding in terms of aroma harmony and structural integrity, with a 29.73% increase in phenylethyl alcohol content, imparting a rose-like fragrance to the wine. Sensory evaluation indicated that nitrogen supplementation combined with sequential inoculation can significantly enhance the aroma and taste of wine, resulting in the best overall quality.