Enrichment of chicken table eggs with lycopene and astaxanthin

Abstract

Ensuring an attractive commercial appearance of egg yolks involves the introduction to the feed of laying hens of the dyes of various origins. Recently, egg producers have preferred natural dyes, which include carotenoids: lycopene and astaxanthin, which can be deposited in chicken egg yolks. The aim of this study was to determine the quality of egg yolks, colour intensity and carotenoid composition of yolks when oil extracts of lycopene (20, 40 and 60 mg/kg feed) or astaxanthin (10, 20 and 30 mg/kg feed) are included in the chickens’ diet. 45 High Line W36 chickens at the age of 24 weeks were used for the experiment. Feeding laying hens with supplements of lycopene oil extracts at doses of 30, 40 and 60 mg/kg and astaxanthin at doses of 10, 20 and 30 mg/kg of feed for 30 days in increasing concentrations did not affect egg weight, albumen height, Haugh unit, strength and the thickness of the shell. The addition of lycopene to the diet of chickens at doses of 20 mg/kg of feed increased the content of lycopene, unidentified carotenoids and the total content of carotenoids in the yolks, but did not change the intensity of their colour. Increasing the dose of lycopene in the diet of chickens to 40 and 60 mg/kg of feed increased the content of lycopene in yolks and the intensity of their colour to 7.4 and 8.0 points against 5.6–6.1 points in the control, but did not affect the content of β-carotene and total carotenoids in the yolks. The addition of astaxanthin oil extract at doses of 10, 20 and 30 mg/kg of feed increased the content of astaxanthin, β-carotene and total carotenoids in chicken egg yolks and increased the intensity of their colour to 12.8, 14.8 and 14.4 points on a 16-point colour scale YolkFanTM. To obtain chicken table eggs with a given colour of the yolks, it is advisable to use the addition of astaxanthin oil extract in doses from 10 to 20 mg/kg of feed for 30 days. The results of the research can be used to develop a technology for the production of functional table eggs enriched with carotenoids of natural origin with an attractive colour for consumers.

Keywords

• yolk colour; carotenoids; quality of eggs; colour scale.