茶多酚改性对聚乙烯醇膜吸湿特性及抗氧化活性的影响  

Effect of Tea Polyphenols on Moisture Absorption and Antioxidant Activity of Poly-(vinyl alcohol)-Based Film

作　　者：陈晨伟[1,2] 段恒[1] 贺璇璇 谢晶[1,2] 杨福馨[1,2] 俞骏[1] 赵旖妮 

机构地区：[1]上海海洋大学食品学院,上海201306 [2]上海水产品加工及贮藏工程技术研究中心,上海201306

出　　处：《食品科学》2016年第1期40-44,共5页Food Science

基　　金："十二五"国家科技支撑计划项目(2013BAD19B06);国家高技术研究发展计划(863计划)项目(2012AA092301);上海研发公共服务平台建设专项(11DZ2292800);上海市高校青年教师培养资助计划项目(B-5409-13-0014);上海海洋大学青年科研基金项目(A-0209-13-0600429);上海市大学生创新项目(201531015059)

摘　　要：研究含不同质量分数茶多酚的聚乙烯醇膜的吸湿特性和抗氧化活性。通过等温吸湿实验研究了含不同质量分数茶多酚(0%、0.5%、1%、1.5%、2%)的聚乙烯醇膜的吸湿特性,并基于常用的等温吸湿模型对实验数据进行拟合表征;通过1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除实验分析了薄膜的抗氧化活性。结果表明:含不同质量分数茶多酚的聚乙烯醇膜均具有吸湿性,其等温吸湿曲线整体变化趋势相似,属于Ⅱ型等温吸湿曲线;薄膜的平衡含水率随水分活度的增加而显著增加(P<0.01),当水分活度大于0.6时,其平衡含水率增加幅度增大;茶多酚对聚乙烯醇膜的改性增加了其疏水性,在相同水分活度条件下,薄膜的吸湿性能随薄膜中茶多酚质量分数的增加而下降,但5种聚乙烯醇膜之间差异不显著(P>0.05);GAB等温吸湿模型对薄膜吸湿性能的拟合效果最好,R^2≥0.996;茶多酚对聚乙烯醇膜的改性使其具有抗氧化活性,DPPH自由基清除率随着薄膜中茶多酚质量分数的增加而显著提高(P<0.01),表明经茶多酚改性后的聚乙烯醇膜的抗氧化性能随薄膜中茶多酚质量分数的增加而增强。经茶多酚改性的聚乙烯醇膜具有吸湿和抗氧化功能,预示其作为塑料复合薄膜内层或中间层应用于湿度敏感型、含高脂肪等干燥易氧化食品包装具有较好的前景。The moisture absorption and antioxidant activity of poly-（vinyl alcohol）（PVA）-based active packaging film containing tea polyphenols（TP） with different concentrations（0%, 0.5%, 1%, 1.5%, and 2% of dry PVA weight） were investigated. Its moisture absorption characteristics were studied through moisture absorption experiment and the experimental data were fitted based on the frequently used moisture absorption isotherm model. The antioxidant activity was determined through DPPH radical scavenging array. The results showed that all PVA films had water absorbability and were generally similar with respect to their moisture absorption isotherms, which belonged to type Ⅱ moisture absorption isotherm. The equilibrium moisture content of all PVA films increased significantly with increasing water activity（P 0.01）, especially when the water activity exceeded 0.6. The hydrophobicity of PVA films was enhanced by TP modification. So the moisture absorption capacity reduced as the quantity of tea polyphenols in the PVA film increased under the same water activity condition, but there was no significant difference among five PVA films（P 0.05）. The experimental data were best fitted with the GAB moisture absorption isotherm mode（R^2 ≥ 0.996）. The DPPH radical scavenging experiment showed the inhibitory rate of PVA films higher in TP was higher than that lower in TP（P 0.01）. It was shown that the antioxidantactivity of the PVA films was enhanced with increasing quantity of TP in films, suggesting that there will be a good prospect of this active packaging film served as inner layer or intermediate layer in the packaging system to improve the storage quality of moisture-sensitive and lipid-containing foods.

关 键 词：聚乙烯醇 茶多酚 活性包装膜 吸湿 抗氧化活性 

分 类 号：TS206.4[轻工技术与工程—食品科学]