Total Polyphenol Distribution and Extraction of Polyphenols from White Peel of Pomelo 

Abstract

Pomel has many polyphenol contents, the antioxidant compound group has many health benefits This study was conducted to investigate the distribution of total polyphenols in pomelo and the extraction condition of polyphenol, naringin, antioxidant capacity (DPPH) from the white peel of pomelo. The results of the study showed the fruit flesh had the highest percentage of weight at 48.6%; followed by the white peel accounting for 25.20%, the green peel accounted for 18.70% and the flesh membrane accounted for 7.5%. However, the distribution of mass and the distribution of total polyphenols is different; Specifically, the white peel accounted for a percentage of total polyphenols of 40.32%, the green peel accounted for 25.21%, the flesh accounted for 22.39% and the flesh membrane accounted for 12.15%. The white peel (a by-product of pomelo processing) selected as a polyphenol extraction material. The results also showed that the percentage of Pectinex Ultra SP-L supplementation, hydrolysis temperature and extraction time had a statistically significant effect (p <0.05) on the total polyphenol content, naringin content and antioxidation capacity. Using 50% ethanol extraction solvent with assisted enzyme; in which, the enzyme rate added 1%; hydrolyzed at 50 ℃ for 1 hour for the extract with the highest total polyphenol content, DPPH oxidation resistance, and highest naringin content of 19.48 mg GAE / g dry matter, 1.79 mg AAE / g dry matter and 5.85 mg NE / g dry matter.