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塑化剂度对基于聚乙醇和化粉混合物的薄膜和涂层的影响
Jaiane Maiara Petry1, Michelly Cristina Galdioli Pellá2, Otavio Augusto Silva2
1Center of Engineer and Exact Sciences, State University of West Parana, 85903-000 Toledo, PR, Brazil.
Food chemistry
|November 17, 2023
概括
这项研究探讨了用比醇 (S) 塑化的聚乙烯醇 (PVA) 和阴阳性粉 (CS) 薄膜. 最佳的混合物,PVA75CS25S15,有效地减少了acerola水果的水分损失,显示出作为食品涂层的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 食品科学 食品科学 食品科学
背景情况:
- 聚乙醇 (PVA) 和阴性粉 (CS) 是可生物降解的聚合物,在食品包装中具有潜在的应用.
- 塑化剂对于提高聚合物薄膜的灵活性和可加工性至关重要.
- 比醇是一种常见的塑化剂,用于食品级材料.
研究的目的:
- 为了研究不同度的比醇对PVA/CS混合膜的特性的影响.
- 评估这些薄膜作为新鲜水果,特别是acerolas的潜在涂层的性能.
- 为了确定最佳的酸盐含量,以实现所需的薄膜特性.
主要方法:
- 制备含有15.0%,22.5%和30.0%索尔比托的PVA/CS混合薄膜.
- 用光谱分析 (FTIR) 来确认聚合物-可塑剂相互作用.
- 显微镜 (SEM) 观察薄膜表面形态和酸盐结晶.
- 测量水蒸气传递率 (WVTR) 和可溶性.
- 将表现最佳的薄膜作为涂层应用于acerola水果上,以评估减少水分损失.
主要成果:
- 光谱数据证实了PVA,CS和sorbitol之间的相互作用.
- 在薄膜表面上观察到比醇结晶,特别是在更高度下.
- 薄膜的水蒸气传递率较低,PVA75CS25S15的值为7.703 g h-1 m-2.2.
- 含CS含量较高的薄膜具有较低的可溶性.
- 增加sorbitol含量超过15%并没有显著改善薄膜特性.
- 与未涂层的对照组相比,PVA75CS25S15涂层减少了acerolas中的水分损失的1.15倍.
结论:
- 对于PVA/CS薄膜,合醇的最佳度为15%.
- PVA/CS混合膜具有有利的特性,如低WVTR和溶解度,使其适用于食品应用.
- 通过减少水分损失,PVA75CS25S15混合物显示出显著的希望,作为有效的涂层,通过减少水分损失来延长新鲜产品的保质期.
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