半纤维素基复合保鲜膜的制备及其性能研究

Investigation on Preparation and Properties of Hemicellulose-based Composite Cling-film

关键词:  半纤维素  聚木糖  聚乙烯醇  茶多酚  保鲜  复合膜

Key Words:hemicellulose  xylan  polyvinyl alcohol  tea polyphenols  fresh preservation  composite film

摘要:本研究以聚木糖（Xylan）和聚乙烯醇（PVA）为主要原料，茶多酚（TP）为抑菌剂制备复合保鲜膜，并将其用于圣女果的贮藏保鲜，主要考察了TP添加对复合保鲜膜强度、阻隔和抑菌性能以及圣女果保鲜效果的影响。结果表明，以聚木糖和PVA总质量为基准，相比未添加TP的对照样，当TP含量为5.26%时，复合保鲜膜的拉伸强度和断裂伸长率分别提高116.6%和113.5%，净水蒸气转移率下降43.1%。用此工艺条件下制备的复合保鲜膜成膜液涂覆在圣女果表面，在温度23℃、相对湿度67%环境下贮藏15天后，与对照样相比，圣女果的质量率下降27.8%，硬度提高13.8%，可滴定酸和维生素C含量分别提高70.6%和62.0%；对大肠杆菌和金黄色葡萄球菌的抑菌圈显著增大，分别增加了2.23 mm和3.5 mm。

Abstract:In this study， the xylan and the polyvinyl alcohol（PVA）were used as the main raw materials， and the tea polyphenols（TP）was used as antibacterial agents to prepare composite cling-film. The film was utilized for the storage and fresh preservation of cherry tomato. The effects of the addition of TP on the strength， barrier and antibacterial performance of composite film as well as fresh preservation effect towards cherry tomato were investigated. The results showed that，compared with the film without TP added， the tensile strength and elongation at break increased by 116.6% and 113.5%， respectively， the net water vapor transfer rate decreased by 43.1% when the dosage of TP was 5.56% （compared with the total weight of xylan and PVA）. The film-forming solution prepared under this process condition was coated on the surface of cherry tomato， and the fruit was then stored under the conditions of 23℃ and relative humidity 67% for 15 days. Compared with the control sample， the weight loss rate of cherry tomato decreased by 27.8%， the hardness increased by 13.8%， and the contents of titratable acid and vitamin C increased by 70.6% and 62.0%， respectively. The inhibition zone against Escherichia coli and Staphylococcus aureus increased significantly 2.23， 3.5 mm， respectively.