Abstract: The changes in aroma ester compounds contents and in strawberry slices during drying were analyzed by headspace-solid phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS). Enzymatic activities related to ester compounds were also studied. The results showed that esters such as ethyl caproate, octyl acetate, ethyl octyl caprylate and ethyl decanoate, were formed during the process of strawberry drying. Principal component analysis (PCA) showed that the synthetic score of ester aroma compounds in strawberry slices dried for 15 hours was the highest. Correlation analysis showed that ethanol dehydrogenase was positively correlated with the contents of ethyl esters of some acids, octyl acetate, (S)-3-hydroxybutyrate methyl ester and other aroma ester compounds. There was a significantly positive correlation between alkyl transferase activity and the contents of some acetate esters, methyl caproate and ethyl octanate. Lipoxygenase was positively correlated with the contents of octyl acetate, hexyl acetate, methyl caproate, ethyl butyrate, ethyl decanoate and butyl octylide.

Key words: strawberry, esters, enzyme activity, principal component analysis, correlation analysis