Comparative appraisal of antioxidant profile & Shelf life of ghee obtained from cow, goat & buffalo milk

Abstract

This study aims to evaluate the antioxidant potential, predict a shelf life using the Rancimat method, and examine the chemical changes that take place during accelerated storage at 80°C in ghee made from goat milk, cow milk and buffalo milk by direct heating cream method. To achieve this, we procured fresh raw milk from goats, cows, and buffaloes within the Amreli region, specifically in the Saurashtra region of Gujarat, India. Antioxidant potential assessment was done by calculating %RSA (DPPH and ABTS) and induction period measurement at 130^oC. %RSA by DPPH and ABTS reagent showed that  goat ghee (5.34±0.57, 3.32±0.58%) possessed least antioxidant potential compared to cow ghee (9.24±0.83, 4.42±0.42%) and buffalo ghee (6.19±0.53, 3.40±0.43%). Induction period at 130 ^oC was higher in cow ghee (7.05±0.43 hr) compared to goat ghee (3.14±0.20 hr) and buffalo ghee (6.46±0.16 hr). The extrapolation-based calculation of shelf life for various milk fat samples was conducted using the Rancimat's built-in software, considering different IP values obtained at both 130°C and 140°C. At 37°C, in terms of months, the calculated shelf life of goat, cow, and buffalo milk fat were 3.24±0.51, 8.92±0.54, and 7.25±0.45, respectively, while at 80°C, predicted shelf life in days were 4.53±0.51, 11.44±0.67, and 9.82±0.35, respectively. Primary and secondary chemical changes during accelerated storage (at 80 ^oC) of ghee samples evaluated using peroxide value, %CD, TBA, and P-AnV. This chemical analysis at 3 days interval showed that higher rate of oxidized metabolite formation in goat ghee compared to cow and buffalo ghee. Overall study indicated that antioxidant potential and shelf life of goat ghee was lower compared to cow and buffalo ghee. PCA analysis exhibited 72.95% and 9.42% of variance on PC1 and PC2, respectively. The results of PCA could assist manufacturers in developing strategies to improve the antioxidant properties of ghee, leading to a longer shelf life and increased customer satisfaction.