Department of Chemistry, State University of Maringa, Av. Colombo, 5790, CEP 87020-900, Maringá, Paraná, Brazil; GIPeFEA, Department of Chemistry, State University of West Paraná, 85903-000, Toledo, Paraná, Brazil.
Department of Chemistry, State University of Maringa, Av. Colombo, 5790, CEP 87020-900, Maringá, Paraná, Brazil.
Int J Biol Macromol. 2019 May 1;128:290-296. doi: 10.1016/j.ijbiomac.2019.01.132. Epub 2019 Jan 25.
Films based on cassava starch have been widely used for fruit coating; however, it is necessary to incorporate other polymers in order to improve mechanical properties, once starch only leads to highly hydrophilic films, compromising their application. In this way, a polymeric blend based on cassava starch, chitosan and gelatin was combined with a plasticizer to produce biodegradable films with satisfactory mechanical and barrier properties, in order to be used as fruit coating. The films were prepared by casting method and a statistical design of 2 was used to evaluate the effect of each polymer and what their combinations would influence over the final product. The formation of a physical blend was confirmed by FTIR. It showed low solubility, varying (10 ± 2) % a (23 ± 4) %, Opacity ranging from (1.06 ± 0.04) to (1.55 ± 0.13) AU x nm/mm, thickness from (0.20 ± 0.01) mm to (0.44 ± 0.03) mm and water vapor transmission rate ranging from 25 ± 0.2 to 30 ± 1.4 g s m. Lower amounts of starch led to more flexible, less opaque and soluble films, while the combination of higher levels of starch and chitosan was responsible for lowering films water vapor transmission rate. Thus, the films showed interesting properties for fruit surface coating.
基于木薯淀粉的薄膜已被广泛用于水果涂层；然而，为了改善机械性能，有必要将其他聚合物结合起来，因为淀粉仅导致高亲水性薄膜，从而影响其应用。通过这种方式，将木薯淀粉、壳聚糖和明胶的聚合物共混物与增塑剂结合，生产出具有令人满意的机械和阻隔性能的可生物降解薄膜，以用作水果涂层。这些薄膜是通过浇铸法制备的，并使用 2 的统计设计来评估每种聚合物的影响以及它们的组合会如何影响最终产品。通过傅里叶变换红外光谱（FTIR）确认了物理共混物的形成。它显示出低溶解度，变化范围为（10±2）%至（23±4）%，不透明度范围为（1.06±0.04）至（1.55±0.13）AU x nm/mm，厚度范围为（0.20±0.01）mm至（0.44±0.03）mm，水蒸气透过率范围为 25±0.2 至 30±1.4 g sm。较低的淀粉含量会导致薄膜更具柔韧性、更不透明和更易溶解，而较高淀粉和壳聚糖水平的组合则会降低薄膜的水蒸气透过率。因此，这些薄膜具有用于水果表面涂层的有趣特性。
