Effect of Selected Stabilizers and Processing Aids on the Stability of a Double Emulsion Encapsulating Bitter Gourd Extract

Abstract

Effect of three variables in differing concentrations [NaCl (3-5%), polyglycerol polyricinoleate (PGPR) (2-4%) and dairy protein-polysaccharide complexes (Whey protein concentrate(WPC-80)-gum Arabic(GA) and sodium caseinate(SC)-gum Arabic in 1:2 ratio)] on the stability of W₁/O/W₂ emulsion matrix that was used to encapsulate bitter gourd extract was evaluated. The double emulsion matrix was characterized by apparent viscosity, zeta potential, turbidity and sedimentation stability by visual appearance. The physical parameters of the double emulsion matrix were very highly significantly (p < 0.001) affected by all variables such as the concentration of salt, PGPR and complex (WPC-GA and SC-P) as well as their interactions. The double emulsions prepared with WPC-GA became unstable immediately after preparation or after one day of preparation. SC-GA stabilized double emulsions were found more stable than WPC-GA stabilized emulsions. A double emulsion containing 5% NaCl, 2% PGPR and 16.5% SC-GA were found most stable (10 days at 37°C) in comparison to other combinations used.