Abstract:Pretreatment of corn steep liquor can solve the problems of poor solubility and aging，in addition to improving its processing characteristics，sensory quality，and the nutrient absorption rate of processed products.In this study，corn grits were used as raw materials and the effects of different pretreatment methods on subsequent enzymatic hydrolysis and the optimal enzymatic hydrolysis conditions of corn steep liquor were determined through single factor and response surface optimization experiments.The results of single factor experiments showed that the explosion puffing treatment was selected as the pretreatment process.The enzymatic hydrolysis conditions of medium temperature α-amylase were as follows:solid-liquid ratio of 1∶5（g/mL），enzyme dosage of 0.4%，enzymatic hydrolysis temperature of 70 ℃，and enzymatic hydrolysis time of 60 min.Under these conditions，the soluble solid content of corn hydrolysate could exceed 13 g/100 mL，and the utilization rate of raw materials exceeded 40%.Based on this，response surface optimization was conducted with dextrose equivalent（DE）value as the index，and the optimal enzymolysis conditions were determined to be as follows:explosion puffing pretreatment of corn grits，solid-liquid ratio of 1∶5（g/mL），α-amylase enzyme dosage of 0.45%，hydrolysis temperature of 70 ℃，hydrolysis time of 80 min，pH value of glucoamylase of 4，enzyme dosage of 0.2%，enzymolysis temperature of 70 ℃，and enzymolysis time of 60 min.Under these conditions，the DE value of the final enzymatic product was higher than 58%.