谷氨酰胺转氨酶改性谷朊粉制备可食性膜的研究

Preparation of edible film with wheat gluten modified by transglutaminase

在乙醇和甘油存在的条件下将谷朊粉用谷氨酰胺转氨酶进行改性,制成可食性膜。制备可食性膜的最佳工艺条件:谷朊粉乙醇溶液浓度为3%,酶浓度为0.67%,甘油浓度为1.8%,成膜液pH为10,乙醇浓度为30%,温度为80℃。在最佳工艺条件下,可食性膜的抗拉强度TS为2.65MPa,断裂伸长率EB为40%。可食性膜的感官评定:颜色微黄,较透明,表面光滑,薄而柔软。对可食性膜进行应用试验:将草莓用可食性膜处理,在常温下放置10d后,相比对照组没有腐烂变质、表面颜色鲜亮、水分损失少、体积变化很小。表明该法制成的可食性膜具有机械性能好,阻隔性好的优点。

The edible film was made of wheat gluten modified by transglutaminase with the existence of ethanol and glycerin. The optimum conditions for edible film were as follows： concentration of gluten was 3%, enzyme concentration was 0.67%, glycerin concentration was 1.8%, ethanol concentration was 30%, temperature was 80 ℃ and pH value was 10. Under these conditions, tensile strength （TS） of the edible film was 2.65 MPa, elongation at break （EB） was 40%. Sensory evaluation of edible film： light yellow, more transparent, smooth surface, thin and soft, a little wheat flavor. Strawberries were processed by the edible film, and placed at room temperature for ten days. Compared with untreated strawberries, the treated strawberries almost weren＇t rotten, more vivid in color, and less moisture loss. It was shown that the edible film made of wheat gluten modified by transglutaminase had advantage on mechanical performance and barrier property.