Insight into the mechanism of synergy of ultrasound and high pressure homogenization on the emulsion stability and interfacial behaviors of α-lactalbumin with mogroside V

Due to uneven distribution amino acid residues of α-lactalbumin (αLA) at oil-water interface, some measurement should be adopted to improve its interfacial behavior and emulsion stability. Therefore, this study focused on the mechanism of synergy of ultrasound and high pressure homogenization on the emulsion stability and interfacial behaviors of α-lactalbumin with mogroside V (MGV). Four treatments were adopted: ultrasound (US), high pressure homogenization (HPH) and combined treatment (US-HPH and HPH-US). Primarily, emulsion stability of αLA/MGV was analyzed. US-HPH or HPH-US exhibited better emulsion stability than US or HPH. Especially, HPH-US-αLA/MGV emulsion was not stratified at the given time (45 d), which was the most stable emulsion. Moreover, the micromorphology of emulsion showed that MGV and UH/HPH treatment suppressed the aggregation of αLA emulsion droplet. In addition, interfacial adsorption mass and viscoelasticity of physical treated αLA was improved with MGV in the order of HPH-US > US-HPH > US > HPH, specifically, frequency shift (ΔF) and dissipation shift (ΔD) of HPH-US-αLA/MGV was 42.2% and 32.5% higher than that without MGV. This finding may provide a potential approach for obtaining natural and high-efficient protein-based emulsifier in food industry.