Protein-based intelligent antibacterial food packaging for preserving freshness of agricultural produce: A review

Protein-based intelligent antibacterial packaging is an innovative smart packaging solution. Its core lies in the ability of the packaging substrate to sense changes in the internal environment of food packaging and trigger the release of antibacterial agents for precise controlled release and quality maintenance. This review explores the potential of six animal and plant protein substrates for fabricating stimulus-responsive antibacterial packaging, including soy protein, corn protein, wheat gluten protein, whey protein, gelatin, and collagen. As natural renewable materials, proteins exhibit excellent biological properties such as biocompatibility and degradability. Meanwhile, their abundant functional groups and unique conformational structures provide good response potential. Moreover, through modification and related treatments, responsive packaging suitable for the preservation of different fruits and vegetables can be constructed. Based on the physiological characteristics of fruits and vegetables after harvest, this review also summarizes the exogenous and endogenous response mechanisms of pH, gas, enzymes, temperature, humidity, and light. Special attention should be given to the role of gas response mechanisms in the postharvest preservation of fruits and vegetables to develop stimulus-responsive packaging suitable for different preservation scenarios of berries, pome fruits, root and tuber vegetables, and leafy vegetables. Finally, this review discusses the challenges in the preparation of stimulus-responsive packaging using protein substrates and points out future research directions, aiming to provide insights for developing safe, effective, and environmentally friendly intelligent packaging, which can serve as a core technology to retard postharvest decay of agricultural produce and extending their shelf life.