Mixed-culture fermentation can enhance cider aroma,but direct co-culture often limits the persistence of non-Saccharomyces yeasts.Among these species,Metschnikowia koreensis is noteworthy for its strong protease and l...Mixed-culture fermentation can enhance cider aroma,but direct co-culture often limits the persistence of non-Saccharomyces yeasts.Among these species,Metschnikowia koreensis is noteworthy for its strong protease and lipase activities that release aroma precursors,yet its interaction with Saccharomyces cerevisiae has not been well characterized.This study evaluated sequential inoculation of M.koreensis and S.cerevisiae with 0 h,24 h,and 48 h delays.A 48-h delay(SM48)extended M.koreensis viability to 9 days,increased ethanol production,and produced sensory attributes characterized by lower sourness and astringency and higher umami and richness.The SM48 group produced the most abundant and diverse volatile compounds,with key fruity and floral esters elevated.OPLS-DA identified these esters as major discriminant contributors,whereas compounds commonly associated with off-flavors such as acetic acid and hexanal were reduced.Metabolic pathway analysis indicated enhanced Ehrlich and esterification pathways with reduced acetate production.Multi-method validation supported that SM48 cider exhibits more complex volatile profiles,stronger fruity and floral notes,and improved color.These results demonstrate that controlled sequential inoculation is an effective approach for improving cider aroma complexity and overall product quality.展开更多
基金financially supported by the National Key Research and Development Project of China[grant number 2023YFD2100304]the Solid-state Fermentation Resources Utilization Key Laboratory of Sichuan Province[grant number 2023GTYY01].
文摘Mixed-culture fermentation can enhance cider aroma,but direct co-culture often limits the persistence of non-Saccharomyces yeasts.Among these species,Metschnikowia koreensis is noteworthy for its strong protease and lipase activities that release aroma precursors,yet its interaction with Saccharomyces cerevisiae has not been well characterized.This study evaluated sequential inoculation of M.koreensis and S.cerevisiae with 0 h,24 h,and 48 h delays.A 48-h delay(SM48)extended M.koreensis viability to 9 days,increased ethanol production,and produced sensory attributes characterized by lower sourness and astringency and higher umami and richness.The SM48 group produced the most abundant and diverse volatile compounds,with key fruity and floral esters elevated.OPLS-DA identified these esters as major discriminant contributors,whereas compounds commonly associated with off-flavors such as acetic acid and hexanal were reduced.Metabolic pathway analysis indicated enhanced Ehrlich and esterification pathways with reduced acetate production.Multi-method validation supported that SM48 cider exhibits more complex volatile profiles,stronger fruity and floral notes,and improved color.These results demonstrate that controlled sequential inoculation is an effective approach for improving cider aroma complexity and overall product quality.
