Optimization of cold-induced aerated gels formed by Maillard-driven conjugates of SPI-gellan gum as an oil substitute in mayonnaise sauce.

Abstract

This research aimed at characterization of composite cold-set aerated gels composed of SPI-gellan gum Maillard conjugates. The optimized gel was eventually incorporated in mayonnaise sauce as an oil substitute. The optimum conditions were statistically determined as 1.5% SPI, 300 mM CaCl₂, and 90 min heating time. All of which resulted 35% glycation degree and high molecular weight conjugates on top of SDS-PAGE injection wells. Increasing CaCl₂ concentration enhanced the adsorption of conjugates at air-water interface, decreasing the density but increasing the WHC and hardness. Increasing heating time facilitated gelation which improved gel hardness. The optimized gel was microstructurally homogeneous with increased overrun (20.8%) and H-bonds. The rheological measurements showed viscoelastic gel network which was thermally stable up to 90 °C, besides increasing G', G" and η∗ at 85 °C. Substitution of optimized gel in mayonnaise sauce improved the nutritional value and thermal stability (77.13%), but declined calorie. The substituted mayonnaise sauce was greatly accepted by panelists. Thus, the aerated gel formed at optimum conditions had great structural and mechanical characteristics and its usage as an oil analogue induced a low-calorie mayonnaise sauce with acceptable sensory properties.