表面活性剂对壳聚糖-乳清分离蛋白-纳米TiO_2复合膜保鲜性能的影响

Effect of Surfactant on Chitosan-WPI-Nano TiO_2 Composite Film on Preservative Performance

为研究表面活性剂对壳聚糖-乳清分离蛋白-纳米Ti O2复合膜(chitosan-whey protein isolate-nano Ti O2composite film,CWTF)在果蔬保鲜应用中性能的影响,将表面活性剂吐温(tween,TW)20、TW60、TW80、TW85分别添加到CWTF成膜液中,测定制备复合膜的拉伸强度、断裂延伸率、透明度及透水性能,并分析表面活性剂对CWTF性质的影响。将加有不同表面活性剂的CWTF涂膜液涂覆到鲜切雷竹笋上,测定其贮藏过程中的质量损失率。结果显示,添加表面活性剂后CWTF表面光滑程度均有不同程度的劣变,按照膜机械性能及透水性能等从优到劣的排序依次为CWTF、CWTF-TW20、CWTF-TW85、CWTF-TW80、CWTF-TW60。涂膜实验结果表明,涂膜组雷竹笋的质量损失率均低于未涂膜组,不同涂膜处理的雷竹笋的质量损失率与膜性质呈负相关。TW20对CWTF的破坏作用最小,为适宜添加表面活性剂,适宜添加体积分数为0.1%。

The objective of this study was to examine the influence of surfactant on the preservative effect of chitosan-WPInano TiO2 composite film(CWTF) on vegetables and fruits. The surfactants tween 20(TW20), TW60, TW80 and TW85 were added to the CWTF film-forming solution, respectively. The tensile strength, elongation at break, transparency and water permeability of the prepared composite membranes were then detected and the effects of the above surfactants on CWTF properties were analyzed. Fresh-cut bamboo shoots were coated with CWTF coating solution added with different surfactants and the weight loss was measured during subsequent storage. Results showed that after adding surfactants, different levels of deterioration on the smoothness of CWTF surface were observed, and the rank according to film mechanical properties and water permeability from high to low was as follows: CWTF > CWTF-TW20 > CWTF-TW85 > CWTF-TW80 > CWTF-TW60. The results of coating experiments showed that weight loss of fresh-cut bamboo shoots with coating was lower than that of those without coating, and was negatively correlated with membrane properties. TW20 was selected as the appropriate surfactant and its appropriate dosage was 0.1%.