Multi-functional behavior of food emulsifier erythorbyl laurate in different colloidal conditions of homogeneous oil-in-water emulsion system

The multi-functional (antioxidative and antibacterial) behaviors of erythorbyl laurate (EL), which is a potent food emulsifier, were comprehensively investigated in oil-in-water (O/W) emulsions under different colloidal conditions. Commercial polysorbate-based emulsifiers with different fatty acid moieties were used as co-stabilizers for stabilizing colloidal suspension of EL, and the droplet size was controlled by adjusting the ultrasonic emulsification conditions such as sonication power and sonication time. The O/W emulsion with EL and Tween 20 showed the strongest antioxidative (lipid peroxide, 35.95 ± 4.05 mmol/kg oil) and antibacterial (D-value, 1.1 h) properties, probably due to their structural similarity of the fatty acid moiety (C12:0). In the case of droplet size, lipid oxidation in the O/W emulsion with EL was lower as the droplet size increased (35.79 ± 5.71 mmol/kg oil at 688.55 nm), and in contrast, the antibacterial property of EL was effectively exhibited in the O/W emulsion of larger droplet size (5.76 ± 0.11 log reduction at 657.93 nm). These results describing the effect of colloidal conditions on the multi-functionality of EL provide critical information pertaining to the application and optimization of EL in the food emulsion industry.