A Study of Selected Characteristics of Hens’ Egg Yolk.

Abstract

The purpose of this investigation was to test the influence of increasing amounts of albumen and selected additives on selected characteristics of liquid egg yolk. Yolks were blended with albumen at levels of 0, 5, 10, 15, 20 and 25% and tested for emulsifying capacity, viscosity, pH and solids content. The emulsifying properties decreased significantly with increased amounts of albumen. At 20% albumen, emulsifying power of yolk was reduced by 50%. Viscosity of liquid egg yolk decreased nearly 80% when diluted with only 10% albumen. There was only a slight increase in pH with addition of up to 25% albumen. The percent solids decreased linearly from 53.2% to 42.4%, as the albumen level increased from 0 to 25%. Since 20% albumen dilution reduces egg yolk emulsifying capacity by nearly 50%, it is suggested that for commercial operations, where emulsifying properties are important, that every effort be made to limit the level of albumen contamination to below 20% and, preferably, to 15%. Addition of sodium stearoyl-2-lactylate at 0.05% significantly (P < 0.01) increased the emulsifying capacity of yolk; however, lecithin at 0.05% significantly reduced emulsifying ability.