Quality changes in fragrant rapeseed oils derived from different varieties during roasting: Focusing on erucic acid and glucosinolate

This study examines the effects of four rapeseed varieties, differing in erucic acid (EA) and glucosinolate (GSL) levels, on the flavor profile of fragrant rapeseed oil (FRO). Total phenolic content and β-tocopherol serve as indicators of FRO's nutritional quality during roasting. Notably, GSLs had a greater effect on the flavor profile than EA. The stronger pungent-like odor in FROs derived from high-GSL rapeseed varieties (LEHG and HEHG) is likely attributed to elevated concentrations of methallyl cyanide, 2,4-pentadienenitrile, 5-(methylthio)-pentanenitrile, benzenepropanenitrile, 6-(methylthio)-hexanenitrile, 5-cyano-1-pentene, 3-methylcrotononitrile, 2-pentenenitrile, and 4-isothiocyanato-1-butene. Additionally, the fatty-like odor was most pronounced in HEHG samples due to increased levels of hexanal, (E,E)-2,4-heptadienal, and nonanal. For LELG and HEHG, the duration of roasting had a more significant impact on the development of FRO flavor than the roasting temperature did. These results may facilitate the selection of rapeseed varieties for FRO production.