Evaluation of Physicochemical Properties of Guar Gum- Antioxidants Emulsion Coatings

Coatings and films with different functional additives for the packaging of food commodities are appealing consumers due to their remarkable benefits. In the present research, total 27 emulsions (E1-E27) were formulated using guar gum (0.25, 0.5 and 0.75 %) with different antioxidants for instance garlic oil (0.125, 0.5 and1%), α-tocopherol (0.2, 0.4 and 0.6 %) and basil oil (1, 2 and 3%). The emulsions, GGOE (guar gum-garlic-oil emulsion), GBOE (guar gum-basil oil emulsion), GATE (guar gum-α-tocopherol emulsion) were analyzed for physicochemical characteristics such as density, surface tension and antioxidant activities by four different methods such as DPPH, ABTS, FRAP and CUPRAC. Lowest surface tension was offered by E1 (0.25 % guar gum + 0.125% garlic essential oil) which improvesspreadability and enhances the adhesion between solution and fruit's surface. E2 (0.25 % guar gum + 0.25% garlic essential oil), E11 (0.25 % guar gum + 2 % basil essential oil) and E19(0.25% guar gum + 0.2% α-tocopherol) showed better results for density. DPPH and ABTS assays showed highest antioxidant activities possessed by E1 and E8 (0.75 % guar gum + 0.5% garlic essential oil) respectively. FRAP and CUPRAC assays showed maximum antioxidant activity by E27 (0.75% guar gum + 0.6% α-tocopherol) and E24 (0.5% guar gum + 0.6% α-tocopherol) respectively. The results suggested that the garlic oil emulsion acquired the best results followed by α-tocopherol emulsion, proved as efficient coatings in terms of physicochemical attributes