Physicochemical properties, aroma compounds, non-volatile metabolites and their potential correlation in Wickerhamomyces anomalus-fermented Sichuan-style sausage

To assess the modulation of <i>Wicker</i> <i>hamomyces (W.) anomalus</i> on aroma compounds, non-volatile metabolites, and their potential correlation in Sichuan-style sausage, in this study, an isolated <i>W. anomalus</i> strain was used as starter cultures to prepare Sichuan-style sausages at different inoculum levels (10⁵, 10⁶, and 10⁷ CFU/g). The results showed that <i>W. anomalus-</i>fermented sausages exhibited reduced total plate counts and stronger antioxidant activity compared to control sausage. UHPLC-MS/MS metabolomics identified 1047 metabolites, of which 930 were characterized. Five metabolic pathways were significantly regulated by <i>W. anomalus</i>. GC-IMS identified 157 aroma compounds, with significant increases of all aromas except acids in <i>W. anomalus</i>-fermented sausages. Strong correlations were observed among physicochemical properties, common differential metabolites and differential aroma compounds (|r| > 0.8, <i>p</i> < 0.05). Twenty-two common differential metabolites were screened likely contributing to aroma formation. This study provides theoretical support for application of <i>W. anomalus</i> in improving the quality of Sichuan-style sausage.