Identification of Volatile Compounds Contributing to Pennycress Aroma

Abstract

Pennycress (Thlaspi arvense L.) is an extremely cold-tolerant oilseed in the mustard family, with an unpleasant mustard-like aroma. This study aimed to identify volatile compounds contributing to pennycress aroma. Wild-type pennycress seeds were evaluated using solvent assisted flavor evaporation (SAFE), combined with gas chromatography-olfactometry (GC-O) and aroma extraction dilution analysis (AEDA). In this research, twenty-nine aroma-active compounds were perceived. With the aid of gas chromatography–mass spectrometry (GC-MS), retention indices, aroma descriptors and standard chemicals verification, ten volatile compounds were identified: 2,5-/2,6-dimethyl-3-methoxypyrazine (grassy), allyl isothiocyanate (onion-like), hexanal (green), (E)-2-octenal (earthy), acetic acid (sour), (E)-2-nonenal (woody), 1-octanol (grassy), 1-nonanol (green), (R)-2-methylbutanoic acid/3-methylbutanoic acid (cheesy) and phenethyl alcohol (rose-like). These results provided the initial aroma analysis of pennycress, which can attract general attention to compounds and metabolic pathways that haven’t been greatly noticed in previous studies, while propose a direction for pennycress breeding programs to design procedures minimizing the undesirable aroma.