Insight into the characteristics of cider fermented by single and co-culture with Saccharomyces cerevisiae and Schizosaccharomyces pombe based on metabolomic and transcriptomic approaches

This study aimed to explore the effect of single and co-culture with Saccharomyces cerevisiae and Schizosaccharomyces pombe on the quality of cider. It was found that the interaction effect was observed in co-culture fermentation (CF) of cider with S. cerevisiae CICC 31084 and S. pombe CICC 1760. Meanwhile, aroma and taste quality of CF was significantly improved involving increase of fruity and floral aroma, which might result from the balance of esters, higher alcohols and terpenes. Moreover, the umami intensity of CF was enhanced, and the taste of sourness and astringency became weaker, which could be due to the higher content of umami amino acid and deacidification of malate. Additionally, a combined metabolic and RNA sequencing analyses revealed a clearer association between flavor quality of cider and gene expression of yeasts. Bioinformatic analysis revealed that the varying genes and metabolites were mainly involved in pathways of carbohydrate, amino acids, energy and terpenes backbone metabolism. Finally, a metabolic pathway visualized the changes of significantly changed metabolites and differentially expressed genes in single and co-culture ciders. This study provided new insights into cider production and facilitated the application of co-culture fermentation technology in fruits cidermaking.