Anti-oxidant activity of Functional Yoghurt Incorporated with Hibiscus rosa-sinensis Flower Extract.

Abstract

Functional yoghurt was developed by incorporating Hibiscus rosa-sinensis flower extract at one and two percent levels. The developed yoghurt was evaluated for physico - chemical parameters, antioxidant activity and sensory qualities. Addition of hibiscus significantly increased the antioxidant activity. The antioxidant activity of control yoghurt was 14.4±0.66 percent whereas the antioxidant activity of yoghurt incorporated with one and two per cent hibiscus flower extract were 19.78±0.66 and 36.32±0.66 percent. The titratable acidity increased with respect to the increase in concentration of hibiscus extract and period of storage. There was a significant increase in total solids content in yoghurt incorporated with two percent hibiscus extract. Hibiscus incorporation had also increased the syneresis percentage of yoghurt. Calcium and Iron content of yoghurt increased significantly in hibiscus incorporated yoghurt. Control yoghurt had 88.97±1.56.mg/100 g calcium and 1.14 ±0.01mg/100 g of iron whereas yoghurt incorporated with one and two percent hibiscus extract had 124.88±1.67, 224.8±1.93 mg/100 g of calcium and 1.43 ±0.01, 1.92 ±0.01mg/100 g of iron respectively. No significant difference was observed in the fat percentage of yoghurt incorporated with hibiscus. Sensory quality of yoghurt was not altered significantly due to the incorporation of hibiscus flower extract. The study revealed that hibiscus flower extract can be incorporated in yoghurt to improve the anti- oxidant property, calcium and iron content of yoghurt without affecting the sensory qualities.