Abstract:In order to investigate the effect of temperature on the quality of passion fruit pulp based on the same sterilization intensity (F=3.0 min), the pulp was sterilized at different sterilization temperatures (88, 92, 95 and 108 ℃)respectively. The changes in physicochemical composition, color and free amino acids were comparatively analyzed, and the flavor analysis was conducted using rapid gas chromatography-electron nose and gas chromatography-mass spectrometry (GC-MS) techniques. The results showed that there was no significant difference in the total acid mass concentration (calculated as citric acid) between all the sterilized samples and the original sample (OS) (P>0.05). Compared to the OS group, the pulp treated at 108 ℃ showed a significant decrease (P<0.05) in the mass concentration of reducing sugars, however, there was no significant difference in the mass concentration of total sugar and total carotenoids (P>0.05), and the retention rate of vitamin C was also the highest (74.93%). Flavor analysis showed that the samples treated at 108 ℃ contained the same kinds of key flavor substances as the OS group, namely ethyl butyrate, ethyl caproate, ethyl acetate, ethyl caprylate and β-dihydroviolone, with a stronger similarity in aroma to the OS group. The samples treated at 92 ℃ had the highest overall free amino acid scores and a higher vitamin C retention rate (62.23%). In conclusion, 108 ℃ is the optimal sterilization temperature to maintain the nutritional compositions and sensory quality of passion fruit when F=3.0 min, and 92 ℃ sterilization is more effective only for sterilization processes below 100 ℃.
