期刊
FOOD HYDROCOLLOIDS
卷 51, 期 -, 页码 281-294出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.foodhyd.2015.05.018
关键词
Chitosan molecular weight; Starch; Mechanical properties; Water vapor permeability; Physico-chemical properties; Microstructural analysis
资金
- UNER of Argentina [PID-UNER 8066]
- ANPCyT of Argentina [PICT 2011 - 1213]
The aim of this work was to prepare and characterize composite films based on chitosan (CH) and corn starch (CS), analyzing the influence of the chitosan molecular weight (MW) on film structure and functional properties. Three chitosan products were characterized and classified as low (LMW), medium (MMW) and high (HMW) according to its MW. Rheological behavior of filmogenic solutions depend on CH-MW from Newtonian to pseudoplastic one. Chitosan based film physicochemical properties were strongly affected by its molecular weight: the lower the MW the higher the color differences and film solubility. SEM observations demonstrated that plasticized chitosan films exhibited homogeneous structures, the higher the MW the more compact is the structure and the lower is the water vapor permeability (WVP, 4.55 +/- 0.6 x 10(-11) g/m s Pa.). Likewise, CH and CS were compatible polymers which led to the development of homogeneous blend films. Polymer interactions were evidenced in FTIR spectra by the shifts observed within the region of 1500-1700 cm(-1), which reduce the hydrophilic groups' availability of chitosan matrices, leading to a reduction in WVP of composite films. Mechanical properties of the developed films were performed through different complementary tests. Chitosan MW affects both the type and number of interactions, which determine the matrix structure and characteristics. In HMW-CH matrix polymerepolymer interactions are favored, leading to strong and resistant matrices with high dynamic elastic modulus values. Meanwhile, in LMW-CH one, polymer-plasticizer and polymeresolvent interactions became important and the development of high extensible and soluble materials is privileged. (C) 2015 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据