Intelligent pH-sensing film based on polyvinyl alcohol/cellulose nanocrystal with purple cabbage anthocyanins for visually monitoring shrimp freshness

作者：He, Yunxia; Lu, Lun; Lin, Yanyun; Li, Ruyi; Yuan, Yuan; Lu, Xuli; Zou, Ying; Zhou, Wei^*; Wang, Zhuo^*; Li, Jihua

来源：International Journal of Biological Macromolecules, 2022, 218: 900-908.

DOI：10.1016/j.ijbiomac.2022.07.194

• Intelligent pH-sensing film
• Cellulose nanocrystals
• Shrimp freshness

We aimed to prepare a new pH-sensing film based on the immobilization of purple cabbage anthocyanins (PCA) into Polyvinyl alcohol (PVA) reinforced by cellulose nanocrystals (CNC). FT-IR, XRD and TGA were used to assess the intermolecular interactions and thermo-stability of films. The addition of CNC and PCA resulted in an enhancement in UV-vis barrier, mechanical properties and moisture resistance. Inclusion of PCA imparted intelligent properties to the films. PCA-loaded films displayed strong visually detectable colorimetric responses to pH (2-13) and volatile ammonia. When applied to monitor shrimp freshness at 4 C, PVA/CNC films containing 0.6 % PCA exhibited conspicuous color fluctuations from purple to gray blue upon deterioration. As a result, PVA/CNC-PCA colorimetric films were considered as intelligent packaging labels with significant mechanical, water vapor barrier properties and pH-sensing qualities for visual quality evaluation of fresh seafood products.

• 单位
  中国科学院; 中国农业大学; 广东海洋大学