Liu Xuanzhuo, Xu Fengfeng, Huang Xiaoqian, Sun Jian, Kan Juan, Liu Jun
College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, China.
Xuzhou Institute of Agricultural Sciences in Jiangsu Xuhuai Area, Xuzhou 221131, China.
Foods. 2025 Apr 5;14(7):1276. doi: 10.3390/foods14071276.
The high hydrophilicity of biopolymer-anthocyanin intelligent packaging films seriously limits their applications in high-humidity environments. Here, a surface hydrophobization technique was adopted to overcome the hydrophilicity of purple sweet potato (PSP)-based intelligent packaging films through stearic acid (SA) coating combined with heat pressing treatments. The structural characteristics, physical properties, and color changeability of the films were investigated. After SA coating treatment, the surface of the films was loosely covered by thick SA layers. As compared with the untreated PSP films, the SA-coated films displayed lower transparency, mechanical property, moisture content, surface wettability, anthocyanin leaching potential, and color changeability. When the SA-coated films were further heat-pressed, the SA-coated layers were closely bound to the films. The heat-pressed films had a higher transparency, mechanical property, and water vapor blocking ability than the SA-coated films. Notably, the color and color changeability of the heat-pressed films were affected by the heat pressing temperature. The films heat-pressed at 100 °C showed a vivid purple color and elevated color changeability, whereas the films heat-pressed at 150 °C showed a brown color and lost color changeability. This study demonstrates that SA coating combined with heat pressing is effective in constructing surface-hydrophobized intelligent packaging films.
生物聚合物 - 花青素智能包装薄膜的高亲水性严重限制了它们在高湿度环境中的应用。在此，采用了一种表面疏水化技术，通过硬脂酸（SA）涂层结合热压处理来克服基于紫薯（PSP）的智能包装薄膜的亲水性。研究了薄膜的结构特征、物理性能和颜色变化特性。经过SA涂层处理后，薄膜表面被厚厚的SA层松散覆盖。与未处理的PSP薄膜相比，SA涂层薄膜的透明度、机械性能、水分含量、表面润湿性、花青素浸出潜力和颜色变化特性较低。当SA涂层薄膜进一步热压时，SA涂层与薄膜紧密结合。热压薄膜比SA涂层薄膜具有更高的透明度、机械性能和水蒸气阻隔能力。值得注意的是，热压薄膜的颜色和颜色变化特性受热压温度的影响。在100°C下热压的薄膜呈现出鲜艳的紫色且颜色变化特性增强，而在150°C下热压的薄膜呈现棕色且失去了颜色变化特性。这项研究表明，SA涂层结合热压对于构建表面疏水化的智能包装薄膜是有效的。
