Green Production of Anthocyanin-Fixed Poplar Veneers toward a Smart Label with Higher and Long-Term Accuracy for Supervising the Freshness of Pork

Abstract

Promising pH-smart films suffer from problems of complicated production, high cost, high energy consumption, and low light barrier. In this study, poplar veneer was used as an alternative to the film matrix. A strategy was realized wherein bleaching and carboxylation were simultaneously developed to construct a green and smart label via alkaline H 2 O 2 treatment and adsorption of mulberry anthocyanins. When the concentrations of H 2 O 2 and NaOH increased to 6% and 0.1 mol/L, the carboxyl content and anthocyanin adsorption amount of veneer reached 1.04 mmol/g and 4.057 mg/g, respectively. The carboxyl content and adsorption capacity of anthocyanins were positively correlated. ALV showed good pH sensitivity and the ability to fix anthocyanins firmly. The color of ALV changed from purplish red to dark blue when the TVB-N of pork reached 14.78 mg/100 g, which was close to the threshold value of GB 2733-2015. This study provides a new material that can help assess the freshness of food in a safe and green way. It achieves a high-value conversion and the utilization of low-quality wood, opening up a new field of wood utilization.