Hydrogels: Characteristics and Application as Delivery Systems of Phenolic and Aroma Compounds

Complex challenges are facing the food industry as it develops novel and innovative products for the consumer marketplace. Food processing and preservation are primarily based on achievement and maintenance of safety in order to protect consumers, as well as extending product shelf life under the relevant conditions of storage, transport and distribution. Maximizing retention of bioactives with recognized positive effects on health typically comes under consideration when the previous two priorities have been achieved. This review introduces the potential applications of hydrogels as delivery systems of high-value bioactives like phenolics and aromas. If they are successfully encapsulated within the gel structures, their release can be controlled, which opens a wide range of applications, not only in food, but also in the pharmaceutical and cosmetic industries. Hydrogels are three-dimensional network structures which can absorb significant amounts of water. They have the ability to thicken the system and therefore can be used to design products with desired properties. In order to preserve the valuable components, it is necessary to know their physicochemical properties, in addition to the properties of the polymer used for hydrogel preparation.