Does anyone know what colour is added to poultry feed now? Back in the 1970 eggs were blamed for reactions by my patients, both keeping their hyperactive children awake at night and aggravating eczema. I learned that tartrazine was used to colour feed. After much fuss by self-help groups and dietitians the dye added to feed was changed to a colour derived from crab shells. Reports of reactions to egg greatly reduced. Those who were allergic to eggs still had reactions.
It has always been known that where chickens have sufficient green grass the yolk colour is strong enough. Isn’t Nature amazing! Before commercial feeds people noticed that yolk colour was lighter at the end of Summer when the grass was dry. Where corn is in the food provided to poultry the yolks will have enough colour. In 2012 I enquired of the Egg Board what was being used. I was told that it was a dye derived from coloured flowers including Marigolds is used. Has anyone got new information on this? One problem is that the poultry feed company can still say it is a natural colour. Even people who have free-range eggs may still add some poultry feed to their feeding program but the amount in eggs would be less.
Tolerance of all suspect foods is dependent on the amount eaten, and tolerance of egg allergy can also be dependant on dose and the amount of cooking. That is why many egg-sensitive people can tolerated eggs in cooking (using allowed tolerated ingredients). To learn more about egg tolerance see The Best Guess guidelines in Tolerating Troublesome Foods which contains information on the risk of reactions of over 300 foods and how to use them while minimising reactions.