Hydrogen-bonded self-assembly coating as GRAS sprayable preservatives for fresh food safety

The implementation of innovative packaging solutions in fresh food is playing an increasingly important role in driving the global transformation towards sustainability. Here, we demonstrated a novel GRAS preservative coating driven by intermolecular hydrogen bond self-assembly between food-derived tannic acid (TA) and gelatin (Gel). The reported TA/Gel coatings feature desirable antibacterial and antioxidant effects and good adhesion ability. Furthermore, the TA/Gel coatings demonstrate excellent performance in different packaging scenarios, demonstrating desirable preservation performance as sprayable coatings. For fresh-cut apples at 4 °C preservations, the shelf life was extended to 14 days with good commercial quality (including preferable color, protective hardness, sugar content, and weight). For fresh lettuce and beef stored at room temperature, the bactericidal rate reached more than 99% and the sensory quality are maintained well. More importantly, the green and minimalist synthesis process we proposed was expected to achieve scale-up production. Therefore, this work represents a technological solution that inspires the application of food-derived GRAS components to solve food safety problems, guiding an innovative trend for future food development.