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Fragrant Brassicaspecies seed oils (FBO) produced in China are mainly obtained from rapeseed (Brassica napus: B. napus) and mustard seeds (Brassica juncea: B. juncea). The characterization and differences of aroma profiles between those two species remain unclear. In this study, the volatile compounds in FBOs were systemically extracted by headspace solid-phase microextraction and solvent-assisted flavor evaporation combined with ultrasound and identified by comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry (GC×GC-TOFMS) and gas chromatography-olfactometry (GC-O). Ninety-three odorants were identified as aroma-active compounds with flavor dilution (FD) factors ranging from 1 to 6561. Moreover, 63 key compounds exhibited their odor activity values (OAVs) to be greater than 1. The oils of the two species were successfully recombinated with their key odorants. B. junceaoils presented stronger pungent-like, pickled-like, and fishy like notes compared to B. napusoils. The key odor differences were primarily attributed to the concentration of 3-butenenitrile, 4-(methylsulfanyl)butanenitrile, 5-(methylsulfanyl)pentanenitrile, 3-isothiocyanato-1-propene, 3-methyl-3-butenenitrile, isothiocyanatocyclopropane, (methylsulfanyl)acetonitrile, dimethyl sulfide, dimethyl trisulfide, and 3-(methyldisulfanyl)-1-propene. This work provides a guide for the selection of raw materials and odor markers in fragrant B. napusand B. junceaoils.

Camellia oil is a popular edible oil in China as a result of its nutritional properties. However, the key odorants of camellia oil remain unclear. In this study, the volatiles of virgin camellia oil (VCO) were extracted by solvent-assisted and non-solvent-assisted methods. A total of 66 volatile compounds were identified using gas chromatography–mass spectrometry–olfactometry, with flavor dilution factors ranging from 1 to 729 via aroma extraction dilution analysis. Among them, 10 odorants were identified for the first time in VCO. Moreover, 41 volatiles were confirmed as aroma-active compounds with odor activity values greater than 1. Aroma recombination and omission studies demonstrated that aldehydes, esters, acids, and heterocyclic compounds significantly contribute to the aroma profiles of VCO. Hexanal, octanal, (E,E)-2,4-heptadienal, (E,E)-2,4-nonadienal, decyl acetate, ethyl benzoate, ethyl 2-methylbutanoate, 2-methylbutyl (Z)-2-methyl-2-butenoate, 2-methylbutanoic acid, hexanoic acid, 2-pentylfuran, and 2-methyl-3-furanthiol could impart roasted-like, nut-like, fat-like, fruit-like, grass-like, and sweat-like odors and were the key odorants in VCO. The lipoxygenase pathway was possibly responsible for the formation of key odorants in VCO. This work provides an extract aroma consistent for virgin camellia oil.