Egg yolk pigmenting properties of lucerne leaf protein concentrate and paprika in a maize based diet

Diets containing varying amounts of lucerne leaf protein concentrate (LPC) and paprika were given to 450 laying chickens for a two-week period. Egg yolk colour was evaluated visually (and using colorimetric analysis) with the Roche yolk colour fan as a standard. The egg yolk colour score changed from 9-11.5 to 13-15 with the addition of lucerne LPC and paprika to the diet. As the level of pigment sources in the diet increased, the dominant wavelength increased and luminosity decreased. Diets containing LPC and paprika can be used to attain egg yolk colours in the desired colour range (visual score 12-14).