A starch-containing food can be improved in its quality by using an enzyme having a glycosyltransferase activity which can covert an a-1,4 bond to an a-1,6 bond and a transglutaminase.藉由使用具有轉換α-1,4鍵結成α-1,6鍵結之糖轉移活性之酵素及轉麩胺醯胺酶(transglutaminase),提昇含澱粉之食品的品質。