Abstract
This study compared the differences in compositional profiles and aroma characteristics between unde-hulled rapeseed oil (U-RO) and dehulled rapeseed oil (P-RO) after microwave pretreatment. Non-volatile metabolomics analysis revealed that U-RO was enriched in aromatic compounds, sulfur-containing compounds, and organic acids, whereas P-RO contained higher levels of terpenoids and alkaloids. Volatile compound analysis indicated that U-RO was associated with cabbage-like and pungent-like attributes, while P-RO exhibited aroma profiles dominated by rose-like, fruity, and nutty characteristics. These differences may be attributed to the thermal transformation of sulfur-containing compounds enriched in the seed coat under microwave treatment, promoting the formation of pungency-related volatiles. Relative odor activity value analysis identified dimethyl trisulfide and dimethyl disulfide as key odor-active compounds, with dimethyl trisulfide exhibiting higher receptor binding affinity and more complex interaction patterns in molecular docking analysis. Overall, dehulling modulated the metabolite composition and aroma characteristics of rapeseed oil, providing a biochemical basis for optimizing rapeseed oil processing strategies aimed at optimizing aroma quality.