蛋清蛋白-木糖美拉德反应产物膜的特性及其膜包裹对核桃仁酸价的影响

蛋清蛋白具有丰富的营养价值和良好的成膜性,是可食用膜的重要材料。但蛋清蛋白膜的阻湿性较差,因此通过美拉德反应对蛋清蛋白进行了糖基化改性,用蛋清蛋白-木糖美拉德反应产物制备膜,试图改善蛋清蛋白膜的阻湿性。首先研究了不同糖类、不同pH、不同加热温度以及不同木糖浓度对蛋清蛋白-木糖美拉德反应进程的影响。并进一步制备蛋清蛋白-木糖美拉德反应产物膜,研究其成膜性以及水蒸气透过率。最后用蛋清蛋白-木糖美拉德反应产物膜对核桃仁进行包裹,考察其对核桃仁酸价的影响。结果表明,蛋清蛋白-木糖美拉德反应产物膜与蛋清蛋白膜相比,水蒸气透过率降低了24%。与未包膜组相比,经过蛋清蛋白-木糖美拉德反应产物包膜的核桃仁酸价降低约30%。蛋清蛋白-木糖美拉德反应产物与蛋清蛋白2种膜包裹对抑制核桃仁脂质过氧化的效果没有明显差别。

Film characteristics of egg white protein Maillard reaction products and its coating effect on walnut rancidity

Egg white protein(EWP) is an important matrix for edible films because of its high nutritional value and good film-forming property.However,there are some disadvantages related to EWP film,such as low water barrier properties.In this study,EWP was glycosylated with xylose through Maillard reaction to improve its properties.The development of Maillard reaction of EWP and xylose was optimized based on contributions of sugar type,pH,heating temperature and xylose concentration to the Maillard reaction.The EWP-xylose Maillard reaction products(EWP-Xyl MRPs) were used to prepare a novel film,and their film-forming property and water vapor permeability(WVP) were investigated in comparison with the EWP film.Furthermore,both of the EWP-Xyl MRPs film and the EWP film were used to coat walnuts,and their effects on walnuts acid value were also investigated.The results showed that the WVP of the EWP-Xyl MRPs film was approximately 24% lower than that of EWP film.Both EWP-Xyl MRPs and EWP films have made the acid value 30% lower than the control group.There was no significant difference between EWP-Xyl MRPs and EWP coating in reduction of acid value.