Colloidal delivery platforms for chlorogenic acid: nano-emulsions, nanoparticles, nanoliposomes, and pickering emulsions in sustainable food preservation.

Chlorogenic acid (CGA), a plant-derived phenolic compound, has attracted considerable attention as a multifunctional bioactive agent due to its potent antioxidant and antimicrobial properties, positioning it as a promising candidate for sustainable food preservation. This review critically compares four colloidal delivery platforms for CGA, nanoemulsions, nanoparticles, nanoliposomes, and Pickering emulsions evaluating their formulation strategies, release mechanisms, and food-preservation performance, and situates them alongside direct treatments and edible coatings/films as complementary, lower-complexity delivery formats. Key aspects, including formulation strategies, functional mechanisms, and preservation performance, are systematically discussed. Analysis of studies published over the past decade reveals that CGA can be integrated into biopolymer matrices such as chitosan, alginate, gelatin, starch, and composites in free form, as grafted conjugates, or via nano delivery systems. The incorporation of CGA significantly enhances the antioxidant capacity, antimicrobial activity, barrier properties, and mechanical stability of edible coatings, leading to effective inhibition of microbial growth, suppression of lipid and protein oxidation, and extended shelf life across a range of food products, including fruits, vegetables, meat, and aquatic products. Emerging evidence also indicates that CGA-functionalized coatings can interfere with key microbial metabolic pathways, including iron acquisition and biofilm formation. Overall, this review highlights CGA as a versatile and sustainable bioactive compound for next-generation food preservation technologies, bridging direct applications with advanced colloidal delivery platforms.