Encapsulated polyphenols in functional food production

Polyphenols are present as nutrient components in many functional food formulations. However, their bioavailability is quite low, and they tend to degrade under extreme technological conditions, e.g., heating, pH, etc. Moreover, polyphenols are known for their specific bitter taste. As a result, a large amount of polyphenols spoils the sensory properties of the finished product. Encapsulation seems a prospective solution to this problem. This article provides a comprehensive review of scientific publications on various methods of polyphenol encapsulation. The review covered publications registered in PubMed, Google Scholar, ResearchGate, Elsevier, eLIBRARY.RU, and Cyberleninka in 2002–2023 with a focus on original research articles published after 2012. The search involved such keywords as polyphenols, encapsulation, flavonoids, delivery systems, and functional products. Encapsulating materials are made of organic or inorganic substances, as well as of their combinations. Mineral salts delay the contact between polyphenols and taste buds. However, they are not resistant enough to gastric juice. In this respect, organic matrices are more effective. Carbohydrates protect active molecules from degradation in the stomach. Liposomes increase the bioavailability of polyphenols. Milk or whey proteins also proved quite effective for a number of reasons. First, they mask the astringent taste, which makes it possible to include more polyphenols in functional food formulations. Second, the resulting product is fortified with valuable proteins and essential amino acids. Third, high concentrations of polyphenols possess enough antioxidant properties to increase the shelf-life. Polyphenol encapsulation is an effective method of functional product design, especially in the sphere of foods made for dietary nutrition, sports, preventive diets, etc.