Analysis of Volatile Organic Compounds in Low-temperature Conditioning of Kiwifruit by HS-SPME-GC-MS Combined with Chemometrics Methods

In order to better solve the problem of kiwifruit aroma during storage, the study utilized 'MiLiang No.1' kiwifruit as the material. The kiwifruit samples were subjected to pre-storage at 0, 4, 8, and 12 ℃ for 3, 5, and 7 d, followed by ethylene treatment for ripening. The volatile organic compounds (VOCs) of the kiwifruit under different temperature pre-storage conditions were analyzed using HS-SPME-GC-MS in conjunction with chemometrics and relative odor activity value (ROAV). The results indicated that a total of 67 compounds were detected, including 17 esters, 8 alcohols, 11 aldehydes, 9 ketones, 5 acids, 13 hydrocarbons, and 4 terpenes. Among them, esters were the most abundant in both variety and content. Furthermore, significant differences were observed in the types and contents of VOCs of kiwifruit under different low-temperature pre-storage conditions (P<0.05). The OPLS-DA model achieved a classification prediction accuracy of 99.5%, and 16 differential VOCs such as phenylethyl alcohol were identified through VIP>1 selection criteria. Furthermore, analysis based on ROAV values revealed 13 key aroma compounds such as ethyl butyrate (1≤ROAV≤100). Aroma profile analysis indicated that kiwifruit samples pre-stored at 4 ℃ for 7 d exhibited a strong fruity aroma, demonstrating superior overall aroma quality. Lastly, PCA factor analysis indicated that the best aroma was achieved under the condition of pre-storage at 4 ℃ for 7 d. This study indicated that low-temperature acclimation technology can better retain the aroma quality of postharvest kiwifruit during storage.