Mechanism of starch degradation of corn grist degermed by extruded at low-temperature and multienzyme synergistic degradation

In order to improve the conversion rate of starch to glucose, an enzyme (α-amylase) was added to amylopectin by changing the α-1,6-glycoside bond in amylopectin by extrusion enzymatic hydrolysis technology, and the microstructure of paraffin section was introduced. Low temperature (≤80 ℃) extrusion, multi-enzyme (α-amylase, glucoamylase, pullulanase) synergistic degumming preparation. The distribution of protein granules and starch granules and the main physicochemical indexes of starch degradation in cells were observed. The results showed that starch content decreased from 81.50% to 74.40% and soluble sugar content increased from 1.07% to 2.26% during extrusion. The change of enzymatic extrusion process was more obvious. By adding α-amylase, starch content decreased from 79.72% to 69.16%, soluble sugar content increased from 6.54% to 7.90%. By adding α-amylase and glucoamylase, the starch content decreased from 81.42% to 72.45%, and the soluble sugar content increased from 11.65% to 14.71%. By adding α-amylase and pullulanase, starch content decreased from 81.31% to 70.31%, soluble sugar content increased from 6.74% to 8.29%. By adding α-amylase, glucoamylase and pullulanase, the starch content decreased from 81.06% to 69.05%, and the soluble sugar content increased from 11.25% to 16.35%. The results of microsection showed that the degradation degree of starch granules in the three enzymes was better than that of one (α-amylase) or two enzymes (α-amylase, glucoamylase or α-amylase, pullulanase). The results showed that starch content decreased, soluble sugar content increased and gelatinization degree increased in degummed maize by low temperature enzymatic extrusion. At the same time, the effect of adding three enzymes (α-amylase, glucoamylase and pullulanase) on starch degradation was better than adding one enzyme (α-amylase) or two enzymes (α-amylase, glucose- amylase or α-amylase, pullulanase). These results provide useful data for improving starch utilization.