Park Su-Il, Zhao Yanyun
Department of Food Science and Technology, Oregon State University, 100 Wiegand Hall, Corvallis, Oregon 97331-6602, USA.
J Agric Food Chem. 2004 Apr 7;52(7):1933-9. doi: 10.1021/jf034612p.
Mineral or vitamin E was incorporated into chitosan-based films: 10-200% (w/w chitosan) Gluconal Cal (GC), a mixture of calcium gluconate and lactate; 5-20% zinc lactate (ZL); and 5-20% alpha-tocopheryl acetate (VE) with acetylated monoglyceride (AM). The functionality of film-forming solutions and dried films was analyzed with standard procedures, and mathematical equations were developed to coordinate selected film functionality with the type and concentration of incorporated mineral or vitamin E. GC incorporation significantly increased pH and decreased viscosity of film-forming solutions, but not the addition of ZL or VE. The water barrier property of the films was improved by increasing the concentration of mineral or vitamin E in the film matrix. The tensile strength of the films was more significantly affected by GC or VE addition than film elongation, puncture strength, and puncture deformation. While a major endothermic peak around 200 degrees C was observed in DSC thermograms of chitosan-based films, only 200% GC incorporation altered this endothermic peak. This study demonstrated the capability of chitosan-based film matrix to carry a high concentration of mineral or vitamin E. Such films may be used for wrapping or coating to enhance the nutritional value of foods.
矿物质或维生素E被添加到壳聚糖基薄膜中：10 - 200%（基于壳聚糖的重量）葡萄糖酸钙（GC），一种葡萄糖酸钙和乳酸的混合物；5 - 20%乳酸锌（ZL）；以及5 - 20%醋酸生育酚（VE）与乙酰化单甘油酯（AM）。采用标准程序分析了成膜溶液和干燥薄膜的功能，并建立了数学方程来协调选定的薄膜功能与添加的矿物质或维生素E的类型和浓度。添加GC显著提高了成膜溶液的pH值并降低了其粘度，但添加ZL或VE则没有这种效果。通过增加薄膜基质中矿物质或维生素E的浓度，薄膜的阻水性能得到改善。与薄膜伸长率、穿刺强度和穿刺变形相比，添加GC或VE对薄膜拉伸强度的影响更为显著。虽然在壳聚糖基薄膜的DSC热重曲线上观察到一个约200℃的主要吸热峰，但只有添加200%的GC改变了这个吸热峰。本研究证明了壳聚糖基薄膜基质能够承载高浓度的矿物质或维生素E。这种薄膜可用于包裹或涂层以提高食品的营养价值。
