Evaluation of pepper spent as an egg yolk colouring agent in the diet of white leghorn layers

Abstract

The egg yolk pigmenting properties of increasing levels (0, 1, 2, 3, 4 and 5%) of pepper spent in the diet of White Leghorn layers was evaluated. Six months old two hundred and forty layers were divided randomly into six groups of 40 layers. Each group was further divided into two replicate groups of 20 layers and assigned to a pen with deep litter. The six treatment diets were assigned to two of the pens at random. Evaluation was based on egg yolk colour intensity measured based on Roche colour fan scores, potassium dichromate grades and consumer preference scores on raw, boiled and fried egg samples. Egg production, feed consumption, feed/dozen eggs, fertility and hatchability of eggs, albumin quality and egg weight were also measured. Significant (p<0.01) differences in Roche colour fan and potassium dichromate scores were obtained. Highest scores for the Roche colour fan (8.63) and potassium dichromate (8.09) grades were attained at the 5% level of pepper spent inclusion, while the lowest values were obtained for the control (0% inclusion). There were also significant (p<0.05) differences in consumer preference scores for boiled eggs. The highest scores (3.51) were given for eggs from birds on the 5% pepper spent diet. No differences (p>0.05) in the preference scores on the raw and fried eggs were observed with all ranging between good and very good. No significant differences (p>0.05) in egg production, feed consumption, feed conversion efficiency, feed cost per dozen eggs, fertility and hatchability of eggs, albumin quality and egg weight were noted. Based on most of the measurements used and maintaining consumer acceptability of the resulting egg products, the closest yolk colour to that of local eggs relished by local consumers was produced by inclusion of 4% pepper spent in the diet. This level of inclusion can, thus, be recommended.


Key words/phrases: Pepper spent, yolk colour, yolk-colouring agent


SINET: Ethiopian Journal of Science Vol.25(1) 2002: 27-34