The effect of pH and xanthan (XG)-locust bean gum (LBG) mixtures on the physical stability of 2 wt% whey protein isolate (WPI) stabilized oil-in-water (O/W) emulsions containing 10% v/v menhaden oil was investigated by measuring particle size, cream stability, viscosity, and microstructure. The O/W emulsions containing .1% XG-LBG mixtures were compared to emulsions with .1% XG and .1% LBG alone along with controls with no gums. The results indicated that creaming is dependent on pH and biopolymer type. At pH 5, all emulsions had similar patterns of phase separation and had no turbidity in the serum phase. The lack of turbidity is likely because at pH 5 the WPI is near its isoelectric point and can be adsorbed more efficiently. This also allows the droplets to aggregate in a similar way and rate in all emulsions at pH 5. Rapid creaming in the XG and XG-LBG emulsions at pH 3 and 5 were a result of flocculation from the complexation of XG-WPI complexes. These complexes were seen to be part of the large floccules in the microstructures. The XG-LBG emulsions at pH 7 showed the greatest resistance to phase separation and resulted in stable emulsions. This is likely because XG and LBG have a strong synergistic interaction that increases viscosity. XG-LBG mixtures can used to form stable emulsions, which can help in development of novel structures and textures to create healthier foods.

Effect of pH and xanthan-locust bean mixtures on the physicochemical properties of whey protein-stabilized oil-in-water emulsions

251st National Meeting (2016)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.