Forghani Samira, Zeynali Fariba, Almasi Hadi, Hamishehkar Hamed
Department of Food Science and Technology, Faculty of Agriculture, Urmia University, Urmia, Iran.
Department of Food Science and Technology, Faculty of Agriculture, Urmia University, Urmia, Iran.
Food Chem. 2022 Sep 15;388:133057. doi: 10.1016/j.foodchem.2022.133057. Epub 2022 Apr 25.
In this research, PVA/Ҡ-carrageenan-based colorimetric indicators incorporated with Centaurea arvensis anthocyanin (CAE) were fabricated by two electrospinning and solvent casting methods and their performance as pH indicators were assessed. Chemical immobilization of CAE on PVA and PVA/Ҡ-carrageenan matrixes was approved by FT-IR analysis. According to SEM images, Ҡ-carrageenanaddition improved the homogeneity of films and decreased the diameter of nanofibers. The crystalline structure and thermal properties of polymeric matrixes were affected by anthocyanin incorporation. CAE had an adverse effect on mechanical properties of films and nanofibers. The preparation method and type of solid matrix affected the responsiveness and the tonality of responded color. Electrospun nanofibers showed high responsiveness (10 s) than colorimetric films (15-40 min) to pH changes. The indicators displayed color variations from heather violet to green over the 2-12 pH range. The designed indicators have potential to be applied as visual pH label in food intelligent packaging.
在本研究中，通过两种静电纺丝和溶剂浇铸方法制备了含有田野矢车菊花青素（CAE）的基于聚乙烯醇/κ-卡拉胶的比色指示剂，并评估了它们作为pH指示剂的性能。通过傅里叶变换红外光谱（FT-IR）分析证实了CAE在聚乙烯醇和聚乙烯醇/κ-卡拉胶基质上的化学固定。根据扫描电子显微镜（SEM）图像，添加κ-卡拉胶改善了薄膜的均匀性并减小了纳米纤维的直径。花青素的掺入影响了聚合物基质的晶体结构和热性能。CAE对薄膜和纳米纤维的机械性能有不利影响。固体基质的制备方法和类型影响了响应性和响应颜色的色调。静电纺纳米纤维对pH变化的响应性（10秒）高于比色薄膜（15 - 40分钟）。在2 - 12的pH范围内，指示剂显示出从石南紫到绿色的颜色变化。所设计的指示剂有潜力应用于食品智能包装中的可视化pH标签。
