Eggs

[Robinia]

I hard boiled a supermarket bought free-range egg & found that the yolk was pure white! What's caused this & would it have been ok to eat? Will the men in white space suits come & take it away in a lead box?!! (have also put this in food & drink but thought anyone who keeps chickens might know)

[New Forester]

The yellow of egg-yolk is from carotenes eaten by the bird. Carotenes are pigments in green plants and in orange and yellow fruit and roots, including the eponymous carrot. It's the yellow of grass covered for a while, when the green chlorophyll has gone. Hens vary genetically in how they deal with carotene. Some breeds have carotenes in their skin and beaks, giving them yellow legs, while others don't and have grey or white skin and legs. Most light-feathered breeds have yellow chicks, with carotenes in the chick down. Some have white chicks instead. Yellow-legged hens' legs become paler when they are laying, because the carotenes are going into the eggs instead -- sometimes this even allows you to tell when a pullet is coming into lay. Bought eggs are generally much paler than free-range, as the birds don't get greens, though they feed some maize to improve yolk colour. I've never seen a truly white egg yolk, but I'd guess that either the hen had been given a very poor diet indeed, or that she perhaps had some kind of mutation preventing carotene deposition in the yolk. Such a mutation might make her eggs infertile -- all that carotene must be doing something useful for the chick, and they may not cope without it. (Bought eggs are of course infertile anyway, as the hens are not kept with males). Or perhaps the white chicks come from white egg-yolks? "Free range"... The legal definition in Europe is very loose, and allows what I'd call very intensive systems. Go for the Soil Association approved products -- these require birds to be kept in small sheds in fields, in smallish flocks, where they can get plenty of greens and don't have to fight everyone else all the time. A price worth paying, I'd say. (Or I can sell you some truly free-range eggs...)

[Robinia]

Amazing information - thanks very much New Forester. Yes, I did know that 'free-range' doesn't necessarily mean they live the life of Riley but I thought that they might be better cared for than many. I'd love to buy truly free-range - live in the Derby area?

[Robinia]

Just occured to me that it's probably a very dumb question to ask someone calling themselves New Forester. It's Friday....

[SteveD]

"...they feed some maize to improve yolk colour." I suppose that what they are doing is ALTERING the yolk colour because customers expect and want the yolk to be yellow. Am I correct in thinking that British people prefer brown-shelled eggs while Americans prefer white-shelled eggs (in spite of the fact that the contents of the shells are essentially identical)?

[New Forester]

Sorry, Noddy -- right the second time. I can run to beef too, for anyone local. SteveD -- yes, UK consumers have traditionally favoured brown -- until Saint Delia's "How to Boil Water" series. She featured white eggs, and the sales went through the roof. And yes, the insides are identical, though I think brown eggs are prettier, especially those with spots. Some breeds lay greenish, blue or pink eggs, too.

[Canib]

Free range eggs? Do they leave the eggs outside to run free?