Influencing emulsifying properties of egg yolk by enzymatic modification by phospholipase D from Streptomyces chromofuscus Part 1: technological properties of incubated egg yolk.

Impact of a direct incubation of egg yolk with phospholipase D (PLD) from Streptomyces chromofuscus was investigated with respect to its effect on rheological and emulsifying properties. Egg yolk has been shown to be a suitable substrate for incubation with PLD after a slight dilution with water (70/30, w/w). A considerable increase of egg yolk viscosity during incubation was observed correlating with formation of phosphatidic acid due to enzymatic activity.

Influencing emulsifying properties of egg yolk by enzymatic modification with phospholipase D. Part 2: structural changes of egg yolk due to incubation.

The effects of a direct incubation of egg yolk (EY) by phospholipase D (PLD) with respect to EY structure and interface properties of oil-in-water (o/w)-emulsions prepared with this EY were investigated. PLD incubation of EY mainly converts phosphatidylcholine into phosphatidic acid (PA). EY structures were characterised using circular dichroism and scanning electron microscopy.