Enhancing physicochemical, aromatic and sensory characteristics in coffee pulp wine through co-culture of indigenous non-Saccharomyces and Saccharomyces cerevisiae

To unlock the potential of indigenous non-<i>Saccharomyces cerevisiae</i> and develop novel starters for enhancing flavor compounds profile and quality of coffee pulp wine (CPW), this study determined the effect of the simultaneous and sequential inoculation of non-<i>Saccharomyces cerevisiae</i> (<i>Wickerhamomyces anomalus</i> YN5) and <i>Saccharomyces cerevisiae</i> KMUC1812 at different inoculation ratios (1:1, 1:5 and 1:10, <i>v</i>/v) on the fermentation kinetics, physicochemical characteristics, phenolic compounds, antioxidant activity, volatile compositions, and sensory properties. Compared with <i>Saccharomyces cerevisiae</i>, mixed starter cultures reduced the content of ethanol, total acid, and flavonoids in CPW, while improving the levels of glycerol, total phenols, total anthocyanins, monomeric phenols and antioxidant activity, especially for 1:5 and 1:10 sequential inoculation. Moreover, the 1:5 and 1:10 sequential inoculations markedly elevated the concentrations of esters and higher-alcohols, imparting intense floral and fruity aromas and achieving high sensory acceptability. Overall, mixed fermentation alongside appropriate inoculation strategies is a potential method for obtaining high-value-added CPW.