Abstract: Thirty-eight, 35 and 32 non-sulfur aroma compounds were identified in three different varieties of prunes, respectively and 4 sulfur-containing compounds in each variety using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame photometric detection (GC-FPD). Hexanol (453.14–6 836.14 μg/kg), (E)-2-hexenal (926.67–4 153.65 μg/kg), hexanal (438.72–3 567.04 μg/kg), (Z)-2-hexenol (194.26–608.03 μg/kg), and phenylacetaldehyde (18.46–446.06 μg/kg) were identified as the main compounds. The results of gas chromatography-olfactometry (GC-O) and odor activity value (OAV) showed higher values for β-damascenone, hexanol, hexanal, 2-methybutanal, (E)-2-hexenal, and 3-methylthiopropanal, indicating that these compounds contribute greatly to the characteristic aroma of prunes. Furthermore, principal component analysis (PCA) revealed significant differences in aroma compounds among different varieties of prunes. Finally, four aroma compounds (β-damascenone, hexanal, 3-methylthiopropanal and (E)-2-pentenal) were selected to verify the accuracy of aroma identification of prunes by S-curve method. The results showed that the aroma compounds contributing greatly to the aroma of prunes had the most significant effects on reducing the threshold of the recombinant liquid and consequently could improve the aroma intensity. This study provides a scientific basis for the effective utilization of prunes.

Key words: prunes; gas chromatography-mass spectrometry; gas chromatography-olfactometry; odor activity value; characteristic compounds; S-curve