Process optimization of thermal stability of mayonnaise based on phospholipase A2 (PLA2) and flavor protease compound enzymatic hydrolysis

Abstract There have been a number of research reports on improving the stability of egg yolk emulsions at home and abroad, while relatively few studies have been conducted on the stability of high internal phase emulsions such as mayonnaise. This study aims to enhance the thermal stability of mayonnaise through composite enzymatic hydrolysis, addressing issues such as oil-phase separation and structural collapse that commonly occur during thermal processing. Comparison of phospholipase A₁(PLA₁) and phospholipase A₂ (PLA₂) showed that PLA₂was more effective in improving emulsion activity (EAI) and emulsion stability (ESI). Subsequently, the response surface methodology was employed to optimize the composite enzymatic digestion process of PLA₂ and flavor protease (Fla), with the optimal conditions determined as 2.3 U of PLA₂, 92 U of Fla, a temperature of 55℃, and a duration of 2 h. Meanwhile, the effects of the primary term PLA₂addition and the interactive terms PLA₂ addition and Fla addition as well as optimal digestion on mayonnaise were investigated. The results showed that the optimized enzymatic hydrolysis process significantly improved the thermal stability of mayonnaise, with an Lightness (L/l*) value of 25.523±0.14. Furthermore, texture and rheological analyses indicated that mayonnaise prepared under optimal enzymatic conditions exhibited greater hardness and stronger force, which is beneficial for its spreadability.This study provides theoretical basis and practical and feasible technical solutions for the production and quality improvement of mayonnaise, and helps its application in more fields, such as refrigerated and frozen foods.