该试验通过美拉德反应制备了玉米蛋白（Zein）基活性保鲜膜，评价了不同接枝度（10.30%、19.25%、28.63%、37.57%）的蛋白-多糖复合共聚物膜对新鲜牛肉的保鲜效果。通过FT-IR和SDS-PAGE证实了美拉德反应中Zein的结构变化以及Zein与大豆多糖之间共价结合的形成，随着美拉德反应程度的增加，Zein水溶液中蛋白浓度由0.11 mg/mL增高至3.06 mg/mL以上。肉质评价结果显示，与对照组牛肉相比，ZS-MRPs膜包裹处理的牛肉在储藏过程中的菌落总数、pH值、色度、TVB-N、TBARs均显著降低（P<0.05）。储藏9 d的不同接枝度的ZS-MRPs膜包裹处理牛肉的菌落总数均低于5 lg CFU/g，pH值低于6.4，TVB-N最高为25.2 mg/100 g，TBARs最高为0.75 mg/kg。接枝度为37.5%的ZS-MRPs膜包裹的牛肉在4 ℃贮藏9 d的各项鲜度指标最佳。以上结果表明，ZS-MRPs接枝复合膜作为一种功能性能好、生物活性高的新型活性包装膜，在肉类食品保鲜上具有良好的应用前景。

Zein-based active cling films were prepared via the Maillard reaction, and the effects of protein-polysaccharide composite copolymer films with different grafting degrees (10.30%, 19.25%, 28.63%, 37.57%) on the preservation of fresh beef were evaluated. FT-IR and SDS-PAGE confirmed the structural changes of zein in the Mallaid reaction and the formation of covalent bonds between zein and soybean polysaccharides. As the Maillard reaction increased, the protein concentration in the zein solution increased from 0.11 mg/mL to over 3.06 mg/mL. Based on the meat quality evaluation results, the total number of colonies, pH, color, TVB-N, and TBARs of beef treated with the ZS-MRPs film coating were significantly reduced during storage compared with those of the control beef (P<0.05). The total number of bacterial colonies of ZS-MRPs film-coated beef with different grafting degrees were lower than 5 lg CFU/g, their pH values were lower than 6.4, the highest TVB-N was 25.2 mg/100 g, and the highest TBARs was 0.75 mg/kg. The freshness index of beef coated in the ZS-MRPs film with a grafting degree of 37.5% was best when stored at 4 ℃ for 9 days. Overall, the ZS-MRPs grafted composite film, which serves as a novel type of active packaging film with good functional performance and high biological activity, has good application prospects in meat preservation.

江苏省农业科技自主创新资金项目（CX(21)3110）