Optimization of Enzymolysis Processing for Pomelo Peel to Produce Reducing Sugar

Peel of Guanximiyou was used as raw material in this study and it was hydrolyzed with pectinase to produce reducing sugar. The hydrolysis of pectinase was optimized by response surface method. Pectinase dosage, enzymolysis temperature, enzymolysis time and solid-liquid ratio were considered as single factors, and the levels of factors were selected on the basis of single factor test. The model was designed according to the Box-Behnken method, and the optimum process parameters for the enzymolysis of pomelo peel were obtained as follows:the solid-liquid ratio was 1:5 g/mL, pectinase addition was 150 U/g and hydrolyzed at 40℃ for 3 h. In this condition, the reducing sugar content in the peel pulp was 21.76 mg/g higher than that before the enzymolysis, which was 2.54 times more than before enzymatic hydrolysi, close to the predicted value of 2.62.It was proved that the enzymolysis processing of the pomelo peel optimized by response surface method was feasible.