以乳清浓缩蛋白为主要原料,通过添加天然抑菌剂,制备抑菌乳清蛋白涂膜液,并用于鸡蛋保鲜.采用单因素试验,研究了乳清浓缩蛋白用量、甘油用量、亚硫酸盐用量和谷氨酰胺转氨酶用量等因素对成膜性能的影响,得到了优化的工艺条件.然后将制备的涂膜液用于鸡蛋保鲜,通过测试鸡蛋挥发性盐基氮、菌落总数等指标,考察涂膜液的保鲜效果.当乳清浓缩蛋白用量为11％、甘油用量为4％、亚硫酸钠用量为0.1％、谷氨酰胺转氨酶用量为0.1％时,涂膜液成膜后具有较好的阻氧、阻水蒸气性能以及良好的力学性能.含有1.0 mg/mL ε-聚赖氨酸和1.0 mg/mL乳酸链球菌素的乳清蛋白涂膜液具有明显的抑菌作用,可以显著延长鲜鸡蛋的保质期.%Whey protein coating with antibacterial activity was prepared by adding different natural antibacterial agent,such as e-polylysine,Nisin,lysozyme and essential oil.The process conditions for preparing whey protein coating were optimized through single factor experiments.The factors including concentration of whey protein,amount of glycerol,sodium sulfite and glutamine transaminage were selected and their effects on the properties of whey protein coating were evaluated.Then the effects of whey protein coating in the preservation of eggs were evaluated and the indexes of TVBN value and total bacterial colonies were investigated.The results showed that when the concentration of whey protein was 11％,the amount of glycerol was 4％,the amount of sodium sulfite was 0.1％,the amount of glutamine transaminage was 0.1％,the barrier properties for oxygen and water vapor and mechanical properties of whey protein coating film were superior.Eggs coated by whey protein coating had better performance in TVBN value,egg contenting total bacterial colonies than control experiments,especially,whey protein coating containing antibacterial agent of 1 mg/mL ε-polylysine and 1 mg/mL Nisin had better fresh-keeping effect,which could prolong the shelf life of eggs more than double.Whey protein coating had a good effect on the preservation of eggs.
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