Integrated analysis of volatilomics and metabolomics reveals the flavor generation in dry-salted radish (Raphanus sativus L.)

Dry-salted radish holds considerable significance owing to its distinctive flavor characteristics. However, the overall profile and formation pathways of the volatile organic compounds (VOCs) remain elusive. This study employed GC–MS-based volatilomics and UPLC-MS/MS-based metabolomics, coupled with multivariate statistical methods such as PCA, PLS-DA, and OPLS-DA to elucidate the dynamic evolution of 120 VOCs and 242 flavor precursor metabolites in both fresh and dry-salted radish over a 60-day salting period. The results demonstrated that variations in the relative content of 12 key differential VOCs, such as erucin and 2-hexenal, play a decisive role in improving the flavor of dry-salted radish, particularly in reducing sulfury, garlic, and cooked onion notes while increasing fruity and sweet flavors. Furthermore, 110 differentially expressed metabolites (DEMs) exert a crucial influence on the flavor property of dry-salted radish, primarily through alpha-linolenic acid metabolism and amino acid-related metabolic pathways involving cysteine and methionine metabolism. Our findings provide valuable guidance for the flavor regulation of dry-salted radish.