Zhao Mou, Yang Huanhuan, Ran Cenchen, Liao Ziyi, Zhai Zihang, Sun Jingtao, Lu Shiling, Ji Hua, Dong Juan
School of Food Science and Technology, Shihezi University, Shihezi, Xinjiang 832000, China; Key Laboratory of Characteristics Agricultural Product Processing and Quality Control (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, School of Food Science and Technology, Shihezi University, Shihezi, Xinjiang 832000, China.
School of Food Science and Technology, Shihezi University, Shihezi, Xinjiang 832000, China.
Food Chem. 2025 Nov 30;493(Pt 2):145802. doi: 10.1016/j.foodchem.2025.145802. Epub 2025 Aug 6.
In this study, the pH values (pH = 4.2, 5.2, 5.6) of chitosan-dialdehyde starch/polyvinyl alcohol (CDS/PVA) and the concentrations of purple sweet potato anthocyanins (PSPA; 0.5, 1.0, 1.5, 2.0 mg/mL) were adjusted to obtain a novel colourimetric film [(PSPA-CDS/PVA)].The infrared spectroscopy and X-ray diffraction showed that the film components were compatible with each other. Additionally, the structure of the films loosened as the pH increased because their tensile strength decreased from 58.850 MPa to 23.052 MPa and the water‑oxygen barrier was weakened (27.624 to 38.406 g·m·h and 0.144 to 0.188 cm·cm·m·day·atm; p < 0.05), promoting volatile ammonia penetration within the films. The films showed better ammonia-responsive colour development and colour stability at a PSPA concentration of 1.5 mg/mL. The colour of 1.5 mg/mL (PSPA-CDS/PVA) changed from purplish-red to bluish-green during mutton refrigeration, accurately indicating mutton freshness and spoilage. The colour signals could also be monitored successfully using the WeChat applet.
在本研究中，调整壳聚糖-二醛淀粉/聚乙烯醇（CDS/PVA）的pH值（pH = 4.2、5.2、5.6）和紫薯花青素（PSPA；0.5、1.0、1.5、2.0 mg/mL）的浓度，以获得一种新型比色膜[(PSPA-CDS/PVA)]。红外光谱和X射线衍射表明，膜成分彼此相容。此外，随着pH值升高，膜的结构变得疏松，因为其拉伸强度从58.850 MPa降至23.052 MPa，水氧阻隔性减弱（27.624至38.406 g·m·h和0.144至0.188 cm·cm·m·day·atm；p < 0.05），促进了挥发性氨在膜内的渗透。在PSPA浓度为1.5 mg/mL时，该膜表现出更好的氨响应显色性和颜色稳定性。在羊肉冷藏期间，1.5 mg/mL（PSPA-CDS/PVA）的颜色从紫红色变为蓝绿色，准确指示了羊肉的新鲜度和变质情况。颜色信号也可以通过微信小程序成功监测。
