Characterization of diacylglycerol oil mayonnaise emulsified using phospholipase A2-treated egg yolk

Abstract Mayonnaise samples were prepared using DAG oil as the oil phase; the properties and stability were compared with mayonnaise samples prepared from TAG oil. Normal (nontreated) egg yolk and phospholipase A 2 (PLA2)‐treated egg yolk were used as emulsifiers. The DAG oil mayonnaise prepared with nontreated egg yolk (DAG‐M) was unstable, with cracks forming within 4 wk at 40°C. This type of fracture was not observed for TAG oil mayonnaise prepared with nontreated egg yolk (TAG‐M). 31 P NMR and quantitative analyses of phospholipids suggested that the phospholipids of egg yolk lipoprotein were dissolved in DAG‐M oil droplets, which might result in the coalescence and fracture of the DAG‐M. Phospholipids were not dissolved in TAG‐M oil droplets. No crack formation was observed for DAG oil mayonnaise prepared with PLA2‐treated egg yolk (DAG‐PLM) after storage for more than 4 wk at 40°C. 31 P NMR spectroscopy and quantitative analyses of phospholipids indicated that the dissolution of phospholipid molecules into the oil droplets was almost prevented in DAG‐PLM. The stability of DAG‐PLM is improved probably because the PLA2 treatment changes the molecular polarity of egg yolk phospholipids and prevents them from dissolution into the DAG oil droplets from oil/water interface.