Liposomal encapsulation for enhancing the retention of antioxidant activity of curcumin incorporated in cookies during baking

Abstract

Functional foods comprise fortified, enhanced, or enriched foods that give health benefits beyond the provision of essential nutrients. Although curcumin possesses numerous beneficial bioactivities, formulation of functional cookies incorporating curcumin is challenging due to its poor solubility, low bioavailability, and instability under different environmental conditions. This study was carried out to investigate the effectiveness of liposomal encapsulation on the retention of the antioxidant activity of curcumin during the baking of fortified cookies. The curcumin-encapsulated liposomes showed a very high encapsulation efficiency, which amounted to 90.58 %. Three types of cookies were prepared using a standard cookie recipe with slight modifications. Those were regular cookies (T1), cookies fortified with 1g/kg free curcumin (T2), and cookies fortified with 1g/kg liposomal curcumin (T3). Sensory and physicochemical properties of the cookies revealed that liposomal curcumin can be incorporated into cookies without any negative effects on the properties of the cookies except color. As expected, the color of the liposomal curcumin incorporated cookies showed, higher yellowness than the regular cookie. The extracts of the cookies were analyzed for antioxidant activity using 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging assay and ferric-reducing antioxidant power (FRAP) assay. Similarly, liposomal curcumin incorporated cookies (T3) exhibited higher antioxidant potential than free curcumin incorporated cookies (T2). In fact, the DPPH radical scavenging activity of T3 and T2 were 92.70 ±3.34%, and 84.73 ±3.37%, respectively, and the FRAP values of T3 and T2, were 683.46 ±91.00 µg/mL and 645.46 ±18.00µg/mL with the reference of ascorbic acid standard respectively. Thus, fortification of cookies with liposomal curcumin may be carried out successfully to retain the antioxidant activity of curcumin during baking.