Abstract: In this study, we used principal component analysis (PCA) to analyze the correlation between the activities of six key enzymes involved in the pathway of fatty acid metabolism, lipoxidase (LOX), alcohol dehydrogenase (ADH), acyltransferase (AAT), hydroperoxide lyase (HPL), phospholipase A1 (PLA-1) and phospholipase A2 (PLA-2) and aroma compounds in Hami melon juice subjected to ultra-high pressure treatment. The results showed that there existed different correlations between the different enzymes and aroma compounds. The first and second principal components contributed to 75.56% and 21.83% (97.39% together) of the total variance, respectively. LOX and PLA-1 activities were found to be highly correlated with esters, aldehydes, ketones and alcohols based on the first principal component. A strong correlation between ADH, HPL, AAT and PLA-2 activities was found based on the second principal component.

Key words: ultra-high pressure, Hami melon juice, enzymes, aroma compounds, principal components analysis