Characterization of aroma-active compounds in Chinese quince (Pseudocydonia sinensis Schneid) by aroma dilution analyses

Aroma-active compounds in the peel and pulp of Chinese quince fruits were extracted by high-vacuum distillation (HVD) and headspace solid-phase microextraction (HS-SPME) methods and identified by gas chromatography-olfactometry (GC-O) combined with aroma dilution analyses. Ethyl 2-methylpropanoate, ethyl (E)-2-butenoate, ethyl 2-methylbutanoate, methional, (Z)-3-hexenyl acetate, β-ionone, ethyl nonanoate, and γ-decalactone were detected as the potent aroma-active compounds (log₃FD factors ≥ 5) in the peel of Chinese quince, while hexanal, (Z)-3-hexenal, and (Z)-3-hexenol, which have a green odor note, were potent aroma-active compounds with high log₃FD factors (≥ 3) in the pulp of Chinese quince. In particular, ethyl propanoate, ethyl (E)-2-butenoate, and (Z)-3-hexenyl acetate—which had sweet and fruity aroma notes with relatively high FD factors—were detected in the samples extracted by HS-SPME.