Effects of region and ripening on the physicochemical properties, microbiome, metabolome, and volatilome of Chinese dry-cured ham

Long-term ripened dry-cured ham is popular across China, but the mechanisms by which production region and ripening time regulate its quality remain incompletely understood. Therefore, the temporal dynamics of multi-dimensional characteristics of Zhejiang Jinhua, Yunnan Xuanwei, and Guizhou Panxian hams were explored. Results showed decreased moisture and fat but increased pH, NaCl, protein, and amino acid nitrogen with prolonged ripening. Bacterial α-diversity and fungal β-diversity were closely related to ripening and region, respectively, while the relative abundance of dominant genera (<i>Staphylococcus</i>, <i>Kocuria</i>, <i>Aspergillus</i>, and <i>Debaryomyces</i>) varied by both factors. GC-TOF-MS and GC-IMS detected 76 non-volatile metabolites (predominantly amino acids and their derivatives) and 84 volatile compounds (mainly alcohols and aldehydes), highlighting the crucial role of region in shaping the metabolic profile. Moreover, correlation analysis and functional prediction confirmed the indispensable contribution of bacteria to quality formation. These results provide scientific support for the high-quality development of the dry-cured ham industry.