Stability of oil–water primary emulsions stabilised with varying levels of casein and whey proteins affected by high-intensity ultrasound |
| |
Authors: | Mayumi Silva Bogdan Zisu Jayani Chandrapala |
| |
Affiliation: | 1. School of Science, RMIT University, Bundoora, Vic., 3083 Australia;2. Spraying Systems, Fluid Air, Spraying Systems Co. Pty Ltd, Melbourne, Vic., 3029 Australia |
| |
Abstract: | This study evaluates physical and chemical stability of ultrasound-assisted grape seed oil primary emulsions stabilised by varying compositions of caseins to whey proteins (80:20, 60:40, 50:50 and 40:60) at different sono-operating conditions (81.9 and 117.0 J mL?1). Physical and chemical stabilities were influenced by both sonication energy densities and milk protein compositions. Emulsions prepared at 81.9 J mL?1 energy density with ≥40% whey protein fraction (60:40, 50:50, 40:60 and WPI) showed greater physical stability than the emulsions sonicated at 117.0 J mL?1 which exhibited physical instability due to the depletion flocculation mechanism at the critical casein concentration (≥40%). The emulsion oxidative stability was found to be affected by sonication conditions as 117.0 J mL?1 induced the oxidation reactions once the whey concentration exceeds 40%. Therefore, ultrasound prepared emulsions with casein to whey ratios of 60:40, 50:50, 40:60 and WPI at 81.9 J mL?1 energy density was found to be stable for 10 days at 4 °C. |
| |
Keywords: | Emulsion stability grape seed oil milk proteins sono-emulsion |
|
|