pH敏感型明胶/琼脂基复合凝胶型包装膜的开发与应用

Development and application of pH-sensitive gelatin/agar-based composite gel packaging films

中文关键词:  智能包装膜  鸡肉保鲜  羧甲基壳聚糖  阿魏酸  花青素

英文关键词:intelligent packaging film  chicken preservation  carboxymethyl chitosan  ferulic acid  anthocyanins

中文摘要:

      目的 开发一种能够保鲜且可以对新鲜度进行可视化监测的新型复合凝胶型包装膜。方法 利用碳二亚胺法将阿魏酸共价接枝到羧甲基壳聚糖(carboxymethyl chitosan, CMCS)骨架上, 合成羧甲基壳聚糖/阿魏酸接枝共聚物(carboxymethyl chitosan-graft-ferulic acid copolymer, CMCS-g-FA), 以明胶和琼脂为成膜基质, 在低于40 ℃条件下引入CMCS-g-FA及花青素, 通过流延法制备复合膜。采用傅里叶变换红外光谱(Fourier transform infrared spectroscopy, FTIR)分析膜的化学结构, 利用质构仪测定其物理机械性能, 并通过测定挥发性盐基氮(total volatile basic nitrogen, TVB-N)、菌落总数、pH、汁液流失率及感官评价, 评估其在鸡肉保鲜中的应用效果。结果 FTIR分析表明CMCS与阿魏酸接枝成功, CMCS-g-FA和花青素能够与明胶/琼脂基质形成稳定的复合膜结构。添加CMCS-g-FA和花青素的复合膜综合性能最佳, 其抗拉强度显著提升至10.410 MPa, 断裂伸长率为35.367%, 水分含量和水溶解性分别为13.21%和39.67%, 此组抑制了鸡肉中微生物的生长及TVB-N的积累, 随着贮藏时间延长, 鸡肉TVB-N由初始的4.3 mg/100 g上升至第6 d的23.36 mg/100 g, 但对比未做保鲜措施的对照组TVB-N低18.83 mg/100 g, 并且pH同时也发生相应变化, 表现了鸡肉从新鲜到腐败的各个阶段。结论 本研究成功开发了一种具有增强机械性能和保鲜功能的智能包装膜, 该膜不仅能实现对禽肉类食品新鲜度的可视化监测, 还能有效延长货架期, 为复合凝胶型包装材料的开发提供了新思路。

英文摘要:

      Objective To develop a novel composite gel packaging film capable of food preservation and visual freshness monitoring. Methods Ferulic acid was covalently grafted onto the backbone of carboxymethyl chitosan (CMCS) using the carbodiimide method to synthesize a carboxymethyl chitosan-graft-ferulic acid copolymer (CMCS-g-FA). Gelatin and agar were used as the film-forming matrix, and CMCS-g-FA together with anthocyanins was incorporated into the matrix at temperatures below 40 ℃. Finally, the composite film was prepared by the solution casting method. The chemical structure of the films was characterized by Fourier transform infrared spectroscopy (FTIR), and their mechanical properties were determined using a texture analyzer. Furthermore, its application efficacy in chicken preservation was evaluated by measuring total volatile basic nitrogen (TVB-N), total viable count, pH , drip loss and conducting sensory evaluation. Results FTIR analysis indicated the successful grafting of CMCS with ferulic acid, and CMCS-g-FA together with anthocyanins could form a stable composite film structure with the gelatin/agar matrix. The composite film incorporated with CMCS-g-FA and anthocyanins exhibited optimal comprehensive properties. Specifically, its tensile strength significantly increased to 10.410 MPa, the elongation at break was 35.367%, and the moisture content and water solubility were 13.21% and 39.67%, respectively. Moreover, this film effectively inhibited microbial growth and TVB-N accumulation in chicken meat. With prolonged storage time, the TVB-N value of the treated chicken increased from the initial 4.3 mg/100 g to 23.36 mg/100 g on the 6th day, which was 18.83 mg/100 g lower than that of the blank control group without preservation measures. Additionally, the pH also showed corresponding changes, reflecting the various stages of chicken meat from freshness to spoilage. Conclusion This study successfully develops an intelligent packaging film with enhanced mechanical properties and preservation functions. The film can not only visually monitor the freshness of poultry meat products but also effectively extend their shelf life, providing a novel approach for the development of composite gel-type packaging materials.