Physicochemical properties of orange oil emulsions prepared using pea protein-alginate conjugates assisted with...

Flavor oil emulsions are important to many acidic beverages. Plant proteins are potential label-friendly but not optimum emulsifiers. In this study, pea protein-alginate conjugates were produced at mass ratios of 2:1, 1:1, and 1:2 by a novel transacylation reaction and were studied at 1.0 % w/v to emulsify 20 % v/v orange oil. Additionally, 0.4-1.0 % w/v soy lecithin was evaluated as a secondary emulsifier. Conjugates alone stabilized emulsions at pH 7.0 visually, but ≥0.8 % w/v lecithin was needed to achieve stability at pH 4.5 and 3.0 during 30-day ambient storage. Lecithin reduced the droplet size, and the co-adsorption of conjugates and lecithin enhanced physical and oxidative stability of emulsions during ambient storage, at increased NaCl concentrations, and after heating at 90 °C for 10 min. The stability enhancement was more significant for conjugates with a higher alginate content. The study is significant for the development of acidic beverages utilizing flavor oils.