米浆制备是发酵米乳饮料加工的重要工艺环节，对成品品质有很大影响。采用单因素试验对米浆制备的三个重要工序：大米焙烤、米浆液化和糖化工艺进行研究，并采用正交试验优化液化和糖化工艺。结果表明：最优的焙烤条件为180 ℃烘烤15 min；最优的液化工艺条件为在温度80 ℃、耐高温α- 淀粉酶加酶量为30 U/g的情况下液化140 min；最优的糖化工艺条件为温度60 ℃、糖化酶加酶量为300 U/g的情况下糖化6 h。在此条件下，可获得淡淡大米香味的米浆，DE值为99.86%，可溶性固形物含量(soluble solid content，TSS)为9.4%。

The preparation of rice slurry is an important process in the processing of rice based fermented beverage, which has a great influence on the finished product quality. The three important processes of rice slurry preparation include: rice baking, liquefaction and saccharification were investigated by single factor experiment, and orthogonal experiments were used to optimize liquefaction and saccharification process. Results showed: the optimal baking conditions were temperature 180 ℃, time 15 min. Liquefaction conditions were 80 ℃, 140 min，thermostable α-amylase enzyme for 30 U/g. Saccharification conditions were 60 ℃, 6 h, glucoamylase dosage for 300 U/g. Under these condition, rice slurry tasted light fragrance of rice, the DE value and soluble solid content（TSS） were 99.86%, 9.4%, respectively.