STUDY ON MODIFICATION OF RED PUMPKIN STARCH (Cucurbita moschata) TO CREATE RESISTANT STARCH USING ENZYME

Abstract

This study aims to determine the parameters of the enzymatic hydrolysis process of red pumpkin starch to increase the resistant starch content in the material. The liquefaction stage was designed with two factors: α-amylase concentration and different times. The results of the α-amylase liquefaction process showed that the highest reducing sugar content was 14.92% at an α-amylase concentration of 11 U/g and time of 50 minutes, with a fixed starch:water ratio is 1:4. The saccharification experiment was carried out based on a multivariate model using the Central Composite Design method yields expected results, with variance analysis in the regression model showing significance (p < 0.05). The reliability of the model R2 = 0.997 showed that the regression model was suitable for the dataset with 99.7% accuracy. CV = 2.08% indicated that the accuracy and reliability of the experiments were good. At a glucoamylase concentration of 112.424 U/ml, a temperature of 48.590°C, and a time of 179.732 minutes, the highest resistant starch content reaches 35.968%. Solubility and swelling increase with temperature: at 90°C, the solubility of native starch and modified starch are 12.12% and 68.85%, respectively, while swelling of native starch is 6.77% and modified starch achieves 3.39%. The transparency of native starch is 5.37% T, while modified starch achieves 2.17% T.