Controlled release behavior of curcumin from kappa-carrageenan gels with flexible texture by the addition of metal chlorides

Previously, we had greatly enhanced the solubility of the widely studied polyphenol curcumin using the tri-component system curcumin/α-glucosyl stevia/polyvinylpyrrolidone. This study aimed to develop a κ-carrageenan gel formulation with a controlled release profile of curcumin by changing the texture properties of the gel. The tri-component system with/without metal chlorides maintained the high solubility of curcumin after five cycles of heating-cooling operations through the interaction between the α-glucosyl stevia micelle-like structure and polyvinylpyrrolidone. The release rate of curcumin in the κ-carrageenan gel formulations was altered by adding metal chlorides. Particularly, changing the concentration of potassium chloride allowed for flexible release of curcumin. Importantly, the κ-carrageenan gel formulation maintained the enhanced solubility of hydrophobic polyphenols, which shows potential for ensuring flexible curcumin-release rates, by changing the texture properties of the gel using metal chlorides. The controlled release rate of curcumin may lead to improved outcomes by prolonging the antioxidant and anti-inflammatory effects of the curcumin in the field of health care.