Raspberry anthocyanin (RA) from Rubus idaeus L. (Rosaceae) and curcumin (Cur) from Curcuma longa L. (Zingiberaceae) can effectively improve the physicochemical properties of composite films, and as bioactive pigment components, they can impart pH-responsive properties to the film. In this study, RA and Cur were added to chitosan/starch/gelatin composite film (CSG) to prepare CSG-RA, CSG-Cur, CSG-RA/Cur₈₂ and CSG-RA/Cur₇₃ color films by solution casting method. The color films could change color under different pH conditions and had higher antioxidant activities using ABTS (2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)) assay. The results from fourier transform infrared spectroscopy and scanning electron microscopy showed that RA and Cur were well dispersed in the CSG matrix and improved the structure of the composite films. The hydrophobic Cur increased the tensile strength from 6 Mpa (CSG) to 14 Mpa (CSG-Cur), but reduced the elongation at break from 55 % (CSG) to 40 % (CSG-Cur). These color films had a good fresh-keeping effect and freshness monitoring, in particular, CSG-RA/Cur₇₃, had the better opacity, water solubility, thickness, moisture content and water vapor permeability than the other films. Briefly, binary pigment films had the potential to become a pH-sensitive indicator/packing film.

Rubus idaeus L. (Rosaceae)的覆盆子花青素 (RA)和Curcuma longa L. (Zingiberaceae) 的姜黄素 (Cur)可有效改善复合膜的理化性能，作为生物活性色素成分，它们可以赋予 pH 响应特性电影。本研究将 RA 和 Cur 添加到壳聚糖/淀粉/明胶复合膜 (CSG) 中，制备 CSG-RA、CSG-Cur、CSG-RA/Cur ₈₂和 CSG-RA/Cur ₇₃溶液流延法彩色胶片。采用ABTS（2,2'-azino-bis-(3-ethylbenzothiazolin-6-sulfonic acid)）法测定，彩色薄膜在不同pH条件下会变色，具有较高的抗氧化活性。傅里叶变换红外光谱和扫描电镜结果表明，RA和Cur很好地分散在CSG基体中，改善了复合薄膜的结构。疏水 Cur 将拉伸强度从 6 Mpa (CSG) 提高到 14 Mpa (CSG-Cur)，但将断裂伸长率从 55% (CSG) 降低到 40% (CSG-Cur)。这些彩膜具有良好的保鲜效果和新鲜度监测，尤其是CSG-RA/Cur ₇₃，具有比其他薄膜更好的不透明度、水溶性、厚度、含水量和水蒸汽渗透性。简而言之，二元颜料薄膜有可能成为对 pH 敏感的指示剂/包装薄膜。