Abstract: An edible film which instantly dissolves in the hot water was developed on the base of soy protein isolate and carboxy methyl cellulose was added as the intensifier and glycerol as the plasticizer.The optimization experiments were performed by means of the orthogonalizing test plan.The results of variance analyses show that the most significant factor for the tensile strength and fracture elongation is the volume fraction of glycerol while that for the instant dissolving rate in the hot water is the drying temperature of the film.The optimized process and formula are obtained for the best instant dissolving rate in the hot water:the drying temperature is 50℃,the mass fraction of soy protein isolate is 4.5%,the mass fraction of carboxy methly cellulose is 0.7%,and the volume fraction of glycerol is 1.0%.

Key words: soy protein isolate, edible film, instant dissolution