Department of Chemistry, College of Arts and Sciences, Northeast Agricultural University, Harbin 150030, China.
Molecules. 2023 Apr 11;28(8):3384. doi: 10.3390/molecules28083384.
The development of intelligent indicator film that can detect changes in food quality is a new trend in the food packaging field. The WPNFs-PU-ACN/Gly film was prepared based on whey protein isolate nanofibers (WPNFs). Anthocyanin (ACN) and glycerol (Gly) were used as the color indicator and the plasticizer, respectively, while pullulan (PU) was added to enhance mechanical properties of WPNFs-PU-ACN/Gly edible film. In the study, the addition of ACN improved the hydrophobicity and oxidation resistance of the indicator film; with an increase in pH, the color of the indicator film shifted from dark pink to grey, and its surface was uniform and smooth. Therefore, the WPNFs-PU-ACN/Gly edible film would be suitable for sensing the pH of salmon, which changes with deterioration, as the color change of ACN was completely consistent with fish pH. Furthermore, the color change after being exposed to grey was evaluated in conjunction with hardness, chewiness, and resilience of salmon as an indication. This shows that intelligent indicator film made of WPNFs, PU, ACN, and Gly could contribute to the development of safe food.
开发能够检测食品质量变化的智能指示薄膜是食品包装领域的一个新趋势。本研究以乳清分离蛋白纳米纤维（WPNFs）为基础制备了 WPNFs-PU-ACN/Gly 薄膜。其中，花青素（ACN）和甘油（Gly）分别用作显色剂和增塑剂，而普鲁兰（PU）的添加则增强了 WPNFs-PU-ACN/Gly 可食用薄膜的机械性能。研究表明，ACN 的添加提高了指示薄膜的疏水性和抗氧化性；随着 pH 值的增加，指示薄膜的颜色从深粉色变为灰色，其表面均匀且光滑。因此，WPNFs-PU-ACN/Gly 可食用薄膜适合用于感应三文鱼的 pH 值，因为 ACN 的颜色变化与鱼的 pH 值完全一致，而三文鱼的 pH 值会随着变质而发生变化。此外，还结合三文鱼的硬度、咀嚼性和弹性来评估暴露于灰色后的颜色变化情况，以此作为指示。这表明由 WPNFs、PU、ACN 和 Gly 制成的智能指示薄膜可以为安全食品的开发做出贡献。
