还原剂对大豆蛋白/聚乙烯醇复合薄膜性能的影响

为了改善大豆蛋白/聚乙烯醇复合薄膜的综合性能，该研究以薄膜拉伸强度、断裂伸长率、透光率、吸水率为评价指标，通过隶属度函数综合评分方法，研究了几种还原剂对大豆蛋白/聚乙烯醇复合薄膜性能的影响。试验结果表明：与对照组相比，加入抗坏血酸或半胱氨酸，薄膜拉伸强度显著增大，吸水率和断裂伸长率显著降低；加入半胱氨酸，薄膜透光率显著提高；添加亚硫酸钠，薄膜拉伸强度和透光率显著提高，吸水率降低但不显著，断裂伸长率无明显变化。当亚硫酸钠质量分数为0.15%时，薄膜综合性能较佳，拉伸强度为6.904?MPa，断裂伸长率为66.076%，透光率为32.310%，吸水率为45.695%。该研究为大豆蛋白/聚乙烯醇复合薄膜性能改善及生产应用提供理论基础。

Effects of reducing agents on common properties of soy protein/ polyvinyl alcohol films

To modified the comprehensive properties of soy protein/polyvinyl alcohol films, the effects of reducing agents on the properties of the films were studied. The tensile strength, elongation, transmittance and water absorption of the films were compared. Furthermore, a vague mathematics model was used to evaluate quality of the films. The results showed that compared with the control, the films with ascorbic acid or L-cysteine exhibited higher tensile strength, but lower water absorption and elongation. The films mixed with L-cysteine exhibited obviously increased transmittance. The tensile strength and transmittance of the films with Na2SO3 were improved significantly, while the elongation and water absorption were decreased unremarkably. With 0.15% Na2SO3, the films exhibited higher evaluation score, and its tensile strength, elongation, transmittance and water absorption were 6.904MPa, 66.076%, 32.310% and 45.695%, respectively. The research contributes to the modification and application of common soy protein/ polyvinyl alcohol films.