Stimuli-responsive protein-based films for next-generation fruit and vegetable preservation: A suggestive review

Post-harvest loss of fruits and vegetables represents a critical global challenge, demanding innovations beyond conventional passive packaging. This review explores the burgeoning field of stimuli-responsive materials, proposing protein-based films as a premier platform for developing next-generation active and intelligent packaging systems. Proteins offer an unparalleled combination of biocompatibility, biodegradability, and functional versatility, making them ideal building blocks for materials that can dynamically interact with their environment. We critically examine a diverse array of fabrication strategies, including layer-by-layer assembly, directed self-assembly, electro-responsive fabrication, and composite material design, highlighting a central "fabrication-function-safety" trilemma that must be navigated for successful translation to food applications. A comprehensive analysis of stimulus-response modalities is presented, categorizing triggers as either intrinsic (pH, enzymes, redox state) or extrinsic (temperature, light, electrical/magnetic fields, water). By synthesizing findings from disparate fields such as biomedicine, soft robotics, and neuroscience, we propose novel biomimetic design paradigms. Specifically, we suggest modeling protective coatings on the human tear film a complex, multi-component system for surface protection and developing "neuro-inspired" sensor arrays that integrate multiple spoilage signals using embedded logic, analogous to biological neural processing. The functional outputs of these smart systems are detailed, focusing on controlled antimicrobial release, modulation of senescence pathways, and intelligent freshness monitoring. This suggestive review concludes by outlining critical knowledge gaps and proposing future research trajectories aimed at creating scalable, food-safe, and highly effective protein-based films, positioning them as a cornerstone technology for reducing food waste and enhancing global food security.