Zhu Jie, Zhang Shuyan, Liu Yujia, Chen Siqian, Li Lin
Key Laboratory of Healthy Food Development and Nutrition Regulation of China National Light Industry, School of Chemical Engineering and Energy Technology, Dongguan University of Technology, Dongguan 523808, China.
Key Laboratory of Healthy Food Development and Nutrition Regulation of China National Light Industry, School of Chemical Engineering and Energy Technology, Dongguan University of Technology, Dongguan 523808, China.
Int J Biol Macromol. 2022 Jan 15;195:41-48. doi: 10.1016/j.ijbiomac.2021.11.138. Epub 2021 Nov 25.
The structures of starch and starch-based materials determine additives migration from material matrix. Propionylated starch derived from waxy, normal, G50 and G80 starch were selected as the matrix, the amylose effect on plasticizer (triacetin) migration as well as structural changes in hydrophobic starch-based films were discussed. The constant (k) of first-order rate and initial release rate (V) of triacetin migration were consistent with the increment of amylose content. Meanwhile, diffusion model disclosed that Fick's second law was apposite to characterize the short-term migration of triacetin, and larger diffusion coefficient (D) values of short- and long-term migration were also found in films with higher amylose content, indicating that amylose-formed structures were in favor of triacetin migration. In comparison of propionylated amylopectin, Van der Waals's interactions between propionylated amylose and triacetin were easier to be weakened with the migration of triacetin, which promoted the decrease of wavenumber of C-O-C, and enlarged the inter-planner spacing of crystalline structures, promoting the formation of amorphous structures and wrinkles and embossments in films with higher amylose content. This work confirmed that regulating the structures of starch were effective to control the migration behavior of additives from starch-based films.
淀粉及淀粉基材料的结构决定了添加剂从材料基体中的迁移情况。选取了由糯性淀粉、普通淀粉、G50淀粉和G80淀粉衍生的丙酰化淀粉作为基体，探讨了直链淀粉对增塑剂（甘油三乙酸酯）迁移的影响以及疏水性淀粉基薄膜的结构变化。甘油三乙酸酯迁移的一级速率常数（k）和初始释放速率（V）与直链淀粉含量的增加一致。同时，扩散模型表明菲克第二定律适用于表征甘油三乙酸酯的短期迁移，并且在直链淀粉含量较高的薄膜中还发现了短期和长期迁移的较大扩散系数（D）值，这表明直链淀粉形成的结构有利于甘油三乙酸酯迁移。与丙酰化支链淀粉相比，随着甘油三乙酸酯的迁移，丙酰化直链淀粉与甘油三乙酸酯之间的范德华相互作用更容易被削弱，这促进了C-O-C波数的降低，并扩大了晶体结构的面间距，促进了无定形结构的形成以及直链淀粉含量较高的薄膜中的皱纹和压纹的形成。这项工作证实了调节淀粉结构对于控制添加剂从淀粉基薄膜中的迁移行为是有效的。
