School of Agricultural Engineering and Food Science, Shandong University of Technology, Xincun West Road, Zibo, Shandong Province 255000, PR China.
School of Agriculture and Food, The University of Melbourne, Parkville, Vic 3010, Australia.
Int J Biol Macromol. 2020 Jun 15;153:892-901. doi: 10.1016/j.ijbiomac.2020.03.018. Epub 2020 Mar 3.
A composite film composed of whey protein isolate (WPI) and psyllium seed gum (PSG) was investigated. Its physicochemical, mechanical and structural properties were determined at different ratios of WPI/PSG (1:0, 3:1, 1:1, 1:3, 0:1). WPI/PSG composite films had higher water contact angle and water vapor permeability, as well as lower oxygen permeability and light transmittance as compared with single WPI or PSG films. With the increase in PSG concentration, higher film brightness and whiteness index, and smaller total color difference were observed. The tensile strength and elastic modulus of the composite film at WPI/PSG ratio of 1:1 was the highest. Elongation at break of composite films was higher than that of the single films. WPI/PSG composite films were more effective than single films in reducing the surface cracks and degree of cracks. XRD revealed a typical semi-crystalline amorphous structure of the composite films. With the increase of the PSG content, higher diffraction peak strength and crystallinity of the films were observed. The results indicated that the properties of the WPI/PSG composite film were superior to that of PSG or WPI film alone. The composite film at WPI/PSG ratio of 1:1 resulted in the highest comprehensive physicochemical and mechanical performance.
研究了一种由乳清蛋白分离物（WPI）和车前子胶（PSG）组成的复合膜。在不同的 WPI/PSG 比例（1:0、3:1、1:1、1:3、0:1）下，测定了其物理化学、机械和结构性能。与单一的 WPI 或 PSG 膜相比，WPI/PSG 复合膜具有更高的水接触角和水蒸气透过率，以及更低的氧气透过率和透光率。随着 PSG 浓度的增加，观察到膜的亮度和白度指数更高，总色差更小。在 WPI/PSG 比例为 1:1 时，复合膜的拉伸强度和弹性模量最高。复合膜的断裂伸长率高于单一膜。WPI/PSG 复合膜在减少表面裂纹和裂纹程度方面比单一膜更有效。XRD 显示出复合膜典型的半结晶无定形结构。随着 PSG 含量的增加，观察到膜的衍射峰强度和结晶度更高。结果表明，WPI/PSG 复合膜的性能优于 PSG 或 WPI 膜单独使用。在 WPI/PSG 比例为 1:1 时，复合膜具有最高的综合物理化学和机械性能。
