Physicochemical properties of yogurt enriched with nanoliposomes containing bitter melon extract

Bitter melon is a medicinal plant for treating many diseases, such as diabetes. However, this plant has a bitter taste, and encapsulation is an appropriate method for its use in food formulations. In this study, bitter melon extract-loaded nanoliposomes were prepared at different concentrations of extract (0.5 and 1%) and lecithin (1, 3, and 5%), and then added to the prepared yogurt. Physicochemical properties and sensory evaluation of yogurt samples were investigated. The results showed that adding encapsulated extract did not affect the pH and acidity of yogurt samples, but it significantly reduced syneresis and increased viscosity. With increasing lecithin concentration, the index L * and b * decreased, and the index a* increased. Sensory evaluation of yogurt samples demonstrated that the samples containing nanoliposomes scored higher in odor, texture, taste, color, and overall acceptability than those containing free extract. Examining charantin release from the nanoliposomes in yogurt in simulated gastrointestinal conditions showed a slow and controlled release. The best model for the release of nanoencapsulated compounds was the first-order equation. The results of this study proved the high efficiency of nanoliposomes for loading the bioactive compounds of bitter melon extract and the possibility of using it in food formulations.