Food Polysaccharides as Stabilizers and Carriers for the Delivery of Polyphenols and Pigments

Polysaccharide-based microparticles have emerged as suitable carriers and stabilizers of active substances, showing potential to stabilize bioactive compounds during storage and gastrointestinal digestion, thereby improving their bioaccessibility and bioavailability. This narrative review provides a comprehensive overview of the main polysaccharides employed as wall materials, including starch, maltodextrin, alginate, pectin, inulin, chitosan, and gum Arabic, and discusses how structural interactions and physicochemical properties can positively influence the microencapsulation of polyphenols and pigments. The principles and main findings of the main microencapsulation techniques, including spray-drying, freeze-drying, extrusion, emulsification, and coacervation, are briefly described. Polysaccharides can entrap both hydrophilic and hydrophobic compounds through physical interactions, forming a barrier around the nucleus or binding to the bioactive compound. Intermolecular binding between polysaccharides in the wall matrix, polyphenols, and pigments in the nucleus can confer up to 90% encapsulation efficiency, primarily governed by hydrogen bonds and electrostatic interactions. The mixture of wall polysaccharides in the microparticles synthesis favors the encapsulation solubility, storage stability, bioaccessibility, and bioactivity of the microencapsulate compounds. Clinical trials regarding the bioefficacy of polyphenols and pigments loaded in polysaccharide microparticles are scarce and require further evidence to reinforce the use of this technology.