Multi-omics insights into key aroma compound formation during Chinese bayberry wine fermentation by Pichia kluyveri...

Pichia kluyveri, a representative non-Saccharomyces yeast, has emerged as a promising starter for enhancing aroma complexity in fruit wine fermentation; however, its molecular basis of aroma modulation, particularly in Chinese bayberry wine, remains poorly understood. In this study, an integrated multi-omics approach was applied to investigate aroma formation and its associated metabolic pathways in bayberry wine fermented by P. kluyveri ZFM-0524. Comprehensive volatile profiling revealed that P. kluyveri ZFM-0524 significantly enriched acetate esters, resulting in a more complex aroma profile than those obtained with Saccharomyces cerevisiae Lalvin ICV D254, Starmerella davenportii DQ-5, and Hanseniaspora uvarum BF-13. Genome analysis (12.43 Mb, 3009 predicted genes) and functional annotation indicated strong metabolic potential in carbohydrate utilization and amino acid catabolism. Flavoromics analysis identified eight key aroma compounds. Transcriptomic profiling further suggested that the synthesis and metabolism of these compounds during fermentation may be closely associated with key pathways such as glycolysis, the citric acid cycle, and amino acid biosynthesis and metabolism. Critical aroma-associated genes, including AAT2, ACS1, ADHs, and AROs, were identified as potential contributors to aroma metabolism. This study provides a systems-level understanding of aroma formation in bayberry wine fermented by P. kluyveri and suggests pathway-level regulatory associations underlying strain-specific aroma enhancement, offering a theoretical basis for precision fermentation using non-Saccharomyces yeasts.