Optimization and release evaluation for tea polyphenols and chitosan composite films with regulation of glycerol and Tween

Abstract In order to optimize the performance of chitosan-tea polyphenols composite films, effects of glycerol and Tween on the antioxidative activities and physical performance of chitosan composite films were evaluated. The results indicated that both flexibility and water vapour permeability of chitosan/tea polyphenols films were improved with the addition of glycerol, meanwhile the solubility and swelling degree decreased. Moreover, the release time of antioxidants from films was delayed with the addition of glycerol. The presence of Tween 20 had no significant effect on the tensile strength of films, but changed the DPPH radical scavenging activity depending on the blend ratio of glycerol and Tween. DSC, FTIR and X-ray analysis showed strong interaction among chitosan, tea polyphenols, glycerol and Tween. The optimum ratio was 0.5% tea polyphenols, 1.2% glycerol and 0.1% Tween. This study provided a reference that an optimized chitosan/tea polyphenols composite film could be obtained by the regulation of glycerol and Tween.

摘要：为优化壳聚糖-茶多酚复合膜的性能，本研究评估了甘油与吐温（Tween）对壳聚糖复合膜抗氧化活性及物理性能的影响。结果表明，添加甘油可提升壳聚糖/茶多酚复合膜的柔韧性与水蒸气透过率，同时降低其溶解性与溶胀度；此外，甘油的添加还延缓了膜中抗氧化成分的释放时长。吐温20（Tween 20）的存在对复合膜的拉伸强度无显著影响，但其对DPPH自由基清除活性的影响会随甘油与吐温的复配比例发生变化。差示扫描量热法（DSC）、傅里叶变换红外光谱（FTIR）与X射线衍射（X-ray）分析结果显示，壳聚糖、茶多酚、甘油与吐温之间存在较强的相互作用。本研究确定的最优复配比例为0.5%茶多酚、1.2%甘油与0.1%吐温，该研究为通过调控甘油与吐温的添加比例制备性能优化的壳聚糖/茶多酚复合膜提供了参考依据。