College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, China.
Institute of Farm Product Processing, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China.
Molecules. 2023 Aug 25;28(17):6243. doi: 10.3390/molecules28176243.
Food packaging films were prepared by using guar gum/polyvinyl alcohol (GP) as the film matrix, 2% Ag nanoparticles (AgNPs) as reinforcing filler and antimicrobial agent, and 1%, 2% and 3% pokeweed betacyanins (PB) as the colorant and antioxidant agent. The structures and color-changing, barrier, mechanical, thermal and antioxidant/antibacterial properties of different films were measured. The results show that the PB were pH-sensitive pigments with pink, purple and yellow colors at pH 3-8, pH 9-11 and pH 12, respectively. PB improved the compatibility of guar gum and polyvinyl alcohol through hydrogen bonds. The films with PB showed a color-changing capacity under ammonia vapor and good color stability in chilled storage. AgNPs and PB elevated the barrier capacity of GP film to light, water vapor and oxygen gas. Meanwhile, AgNPs and PB improved the stiffness, thermal stability and antioxidant/antibacterial activity of GP film. The film with AgNPs and 3% PB showed the highest barrier capacity, stiffness, thermal stability and antioxidant/antimicrobial activity. In shrimp spoilage test, the films with AgNPs and 2% and 3% PB indicated shrimp freshness through film color changes. The results reveal the potential use of the prepared films in active and smart packaging.
采用瓜尔胶/聚乙烯醇（GP）作为膜基质，以 2%的银纳米粒子（AgNPs）作为增强填料和抗菌剂，以 1%、2%和 3%的商陆叶甜菜苷（PB）作为着色剂和抗氧化剂，制备了食品包装膜。测量了不同薄膜的结构和变色、阻隔、机械、热学和抗氧化/抗菌性能。结果表明，PB 是 pH 敏感的颜料，在 pH 3-8、pH 9-11 和 pH 12 时分别呈现粉红色、紫色和黄色。PB 通过氢键提高了瓜尔胶和聚乙烯醇的相容性。PB 使 GP 膜在氨气蒸气下具有变色能力，并在冷藏时具有良好的颜色稳定性。AgNPs 和 PB 提高了 GP 膜对光、水蒸气和氧气的阻隔能力。同时，AgNPs 和 PB 提高了 GP 膜的刚性、热稳定性和抗氧化/抗菌活性。AgNPs 和 3%PB 的膜具有最高的阻隔能力、刚性、热稳定性和抗氧化/抗菌活性。在虾腐败试验中，AgNPs 和 2%和 3%PB 的膜通过膜颜色变化表明虾的新鲜度。结果表明，所制备的薄膜在活性和智能包装中有潜在的应用。
