Effects of Sodium Chloride on the Physical and Oxidative Stability of Filled Hydrogel Particles Fabricated with Phase Separation Behavior

Abstract

The objective of this study was to investigate the influence of sodium chloride (NaCl) concentration (0–500 mM) on the physical and oxidative stabilities of filled hydrogel that were stabilized using heat-denatured whey protein concentrate and high methoxy pectin. Our results showed that with an increase in NaCl concentration, the particle sizes, zeta-potentials, and interfacial layer thickness of filled hydrogels significantly increased and the lightness and whiteness gradually decreased (p < 0.05). Moreover, rheological characterization revealed that the apparent viscosity and viscoelastic behavior gradually decreased at higher NaCl concentration, which was mainly ascribed to the influence of NaCl on the electrostatic repulsion between droplets, thereby adversely impacting the physical stability of filled hydrogels. Furthermore, the result of cryo-scanning electron microscopy also verified the abovementioned results. Notably, higher NaCl concentration significantly promoted the oxidation of lipids and proteins (p < 0.05), thereby decreasing the oxidative stabilities of filled hydrogels. Our results indicated that filled hydrogels prepared under different ionic strength conditions can provide the theoretical basis for their future application in emulsion-based foods.

Protein Oxidation in Foods: Mechanisms, Consequences, and Antioxidant Solutions

“…Salting is a widespread technique of food preservation, but knowledge on the impact of NaCl on protein oxidative stability is limited. Hence, to provide further insight into the redox properties of NaCl on protein oxidation, Cao et al [14] investigated the influence of increasing concentrations of NaCl (0-500 mM) on the oxidative stability of filled hydrogel stabilized with heat-denatured whey protein concentrate. Notably, higher NaCl concentrations significantly promoted the oxidation of lipids and proteins, hence affecting the oxidative stability of filled hydrogels.…”