| dc.description.abstract | The objective of this study was to improve the extraction efficiency and quality of the juice extracted from red dragon fruit (Hylocereus polyrizus), by using commercial hydrolytic enzymes, namely Pectinex Ultra SP-L and Viscozyme L. The two enzymes were applied in constant total rate, but at different combination ratios, at temperatures from 30 to 60oC and with an enzymatic treatment duration from 90 to 150 min. By the effect of the enzymes, the extraction yield was significantly increased while the juice quality was obviously improved. At the total enzyme inclusion rate of 0.1% with a combination of Pectinex Ultra SP-L and Viscozyme L (70/30), at temperature 40oC and in 120 min, highest extraction yield (86.35%) and highest reducing sugar content in the juice (28.87 mg/mL) were obtained. Meanwhile, extraction without enzyme treatment resulted in significantly lower yield (54.04%) and much less reducing sugar content in juice (20.63 mg/mL). Also, by application of the enzymes at optimal conditions, the juice relative viscosity was reduced from 1.42 to 1.09, while the total acidity increased from 0.47 to 0.75 (g/100 mL), the TPC increased from 13.68 to 14.16 (mgGAE/100g puree) and the vitamin C content increased significantly from 27.94 to 32.29 (mg/100g puree) as compared to the treatment without enzymes.
Keywords:
Cellulase, hemicellulase, Hylocereus polyrizus, juice processing, pectinase, Red dragon fruit. | en_US |
