Emulsifying properties of low-fat, low-cholesterol egg yolk prepared by supercritical CO2 extraction

Comparisons were made with native egg yolk, dried egg yolk and a commercial yolk substitute (soy lecithin). Aqueous emulsions were prepared by sonicating water containing 0-5% NaCl, 20% peanut oil, HCl or NaOH as needed for pH adjustment, and 1-3% emulsifier expressed as the total of phospholipids, glycolipids and proteins contributed by yolk ingredients or soy lecithin. The median diameters of fat particles in the emulsions with and without dispersing fat droplet flocs using Triton X-100, were evaluated by laser light diffraction. The emulsifying properties of low-fat, low-cholesterol egg yolk were similar to or better than those of native yolk and dried egg yolk. Soy lecithin had less effective emulsifying properties than yolk ingredients with respect to coalescence of fat droplets during storage and separation during 70 degrees C treatment.