食品模拟体系中疏水性淀粉基膜材的结构变化

Structural Changes of Hydrophobic Starch-Based Film in Food Simulants

为考察疏水性淀粉基食品包装材料与食品模拟体系接触过程中的结构变化,采用扫描电子显微镜、傅里叶红外光谱和小角/广角X射线散射系统分析了淀粉基膜材的显微结构、链结构、分子间相互作用、结晶结构和微区结构.结果表明:在与食品模拟体系的接触过程中,随着模拟体系溶剂的渗透和增塑剂的迁移,淀粉基膜材中大分子链收缩聚拢,微晶结构聚集,晶面距减小,形成更致密的聚集态结构,增塑剂分子受到的作用力增大;淀粉醋酸酯大分子的运动性、溶剂渗透和增塑剂迁移受到更大的内阻力.

In order to reveal the structural changes of hydrophobic starch-based film for food packaging during the contact with food simulants,the microstructure,chain structure,intermolecular interaction,crystalline structure and micro-regional structure of the film were systematically analyzed by means of scanning electron microscopy, Fourier-transform infrared spectroscopy,as well as small and wide angle X-ray scattering technique. The results indicate that,along with the solvent permeation and the plasticizer migration occurring during the contact with food simulants,the macromolecular interaction of the film is enhanced;the microcrystallines aggregate;and the interplanar spacing decreases,thus forming more compact aggregation structure and enhancing the molecular force exerted on the plasticizer. Moreover,it is found that the mobility of starch acetate macromolecules,the solvent permeation and the plasticizer migration are all retarded during the contact with food simulants.