Effects of tocopherols on the stability of flaxseed oil-in-water emulsions stabilized by different emulsifiers: Interfacial partitioning and interaction

The potential effects of tocopherols (100 mu M in emulsions) on the physicochemical stability of whey protein isolate (WPI), soy lecithin (SL), or Tween 20 (TW) stabilized flaxseed oil (FO)-in-water emulsions were investigated. During the storage (18 days at 55 celcius), the particle size, microstructure, and multiple light scattering results showed WPI-stabilized emulsions exhibited better physical stability when tocopherols were added hydroperoxides and TBARS concentration in TW-stabilized emulsions were higher than those of SL or WPI, which were suppressed differently by tocopherols. Among homologues, delta-tocopherol was more effective in inhibiting lipid oxidation than alpha-tocopherol, which was related to the higher interface partitioning. Moreover, the increased interfacial tension indicated tocopherols, especially delta-tocopherol, were adsorbed on the interface and interacted with WPI or SL via hydrophobic or electrostatic interactions determined by isothermal titration calorimetry. Our results suggest tocopherols are more applicable in WPI emulsion systems to achieve steady-state delivery of ALA.

Automated summary

Tocopherols, especially delta-tocopherol, have a potential impact on the physical stability and lipid oxidation inhibition in WPI-stabilized emulsions. These effects vary in different stabilizer systems, with delta-tocopherol showing greater effectiveness compared to alpha-tocopherol.