微波-超声波协同作用对大豆分离蛋白-壳聚糖复合膜性能的影响

本文利用微波-超声波协同作用对大豆分离蛋白-壳聚糖复合膜膜液进行处理,采用浇铸-蒸发方法制备了复合膜。研究了不同微波功率对复合膜的抗拉强度、断裂伸长率、水蒸气透过系数、气体透过率和透光率的影响,此外还进行了红外光谱和扫描电镜分析。结果表明,当微波功率为500 W时,复合膜的抗拉强度(TS)达到最大值21.98±0.54 MPa,其断裂伸长率(E)达到最小值13.48±0.01%;当功率为400 W时,其水蒸气透过系数(WVP)达到最小值为0.61±0.05×10-12 g/(cm·s·Pa),氧气透过率(OP)达到最小值为1.95±0.02×10-5 cm3/(m2·d·Pa);当功率为300 W时,二氧化碳透过率(CO2P)达到最小值1.58±0.12×10-5 cm3/(m2·d·Pa);通过红外光谱分析结果表明,复合膜机械性能及阻隔性能得到了改善,其原因可能是大豆分离蛋白和壳聚糖分子之间产生了氢键或共价键。本文研究结果可以为大豆分离蛋白-壳聚糖复合膜的实际应用提供理论依据。

Effect of Combined Microwave-ultrasound Treatment on the Properties of Soy Protein Isolate-chitosan Composite Films

Soy protein isolate-chitosan mixtures were treated with a combination of micro and ultrasonic waves. This resultant dispersions were then used to prepare composite films using a casting-evaporation method. The effect of different microwave powder on tensile strength, elongation at break, water vapor permeability, gas permeability, and light transmittance of composite films was investigated. In addition, infrared (IR) spectroscopy and scanning electron microscopy (SEM) were also performed. The results indicated that with 500-W microwaves, the tensile strength of the composite films reached a maximum of 21.98 ± 0.54 MPa and the elongation at break reached a minimum of 13.48 ± 0.01%. In contrast, the lowest water vapor permeability [0.61 ± 0.05 × 10-12 g/(cm?s?Pa) ] and minimum oxygen permeability [1.95±0.02×10-5 cm3/(m2?d?Pa)] was obtained with 400-W microwaves. Additionally, with 300-W microwaves, carbon dioxide permeability reached a minimum value [1.58±0.12×10-5 cm3/(m2?d?Pa)]. IR analysis indicated that mechanical and barrier properties of the composite film were improved, probably resulting from hydrogen bonding or covalent bond formation between soy protein isolate and chitosan. These results indicate potential applications for soy protein isolate-chitosan composite films.