Extraction of Pectin from Apple Pomace by Complex Enzymes and Analysis of Product Properties

Abstract:

In order to efficiently extract pectin from apple pomace，extraction of pectin by complex enzymes was studied. Firstly，three kinds of enzymes such as cellulase，xylanase and acid protease which can improve the extraction rate of pectin were selected. Then the optimum enzymes dosage were determined as 7% cellulase，9% xylanase and 5% acid protease. On the basis，the optimal enzymatic extraction parameters，i.e.，pH 4.1，extraction temperature of 54 ℃，extraction time of 1.3 h，solid-liquid ratio of 1：16 were obtained. Under these conditions，the yield of crude pectin was 40.66%，which was increased by 51.49%，compared to 26.84% for the traditional acid extraction method. The properties of pectin obtained from the enzymatic extraction were analyzed. The results showed that the content of galacturonic acid was 57.39%，and the degree of esterification was 89.41%. The range of molecular weight was mainly distributed at 217.63 kDa，16.67 kDa，and 8.17 kDa. It can be used as raw materials to prepare a series of pectin with different degrees of esterification.