PROTEIN-ALGINATE CONJUGATES PRODUCED BY TRANSACYLATION REACTION AS NOVEL EMULSIFYING AGENTS

The overall goal of the present application is to study protein-alginate conjugates formed via the transacylation reaction as novel emulsifying ingredients. The first objective is to prepare protein-alginate conjugates and characterize physicochemical properties. We propose to study dairy proteins with known emulsifying properties (sodium caseinate) and plant proteins with (pea protein isolate) and without (zein, alcohol-soluble corn proteins) known emulsifying properties. Molecular structural changes will be characterized at different reaction conditions. Interfacial properties of the protein-alginate conjugates will be characterized. Aroma attributes of conjugates will be analyzed with descriptive sensory panel. The second objective is to characterize emulsions prepared with the protein-alginate conjugates and sensory properties of model beverages and salad dressings. Orange and olive oils will be studied as representative polar and non-polar oils significant to beverage and salad dressing products, and representative emulsions posing Ostwald ripening and coalescence destabilization challenges. The dimension, structure, and surface characteristics of emulsion droplets during storage and after heating will be characterized. The stability of emulsions against environmental stresses, including pH, ionic strength and multivalent ions, and temperature will be evaluated, as well as the oxidative stability of the oil during storage. Lastly, model beverages with orange oil and salad dressings with olive oil will be prepared and characterized for physical and sensory properties.