What is the reaction, and why does the yolk of an egg go black when boiled?!


Question: What is the reaction, and why does the yolk of an egg go black when boiled!?
When you boil an egg, sometimes the yolk goes a little black on the inside!. is there a chemical name for this and why does it happen
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Answers:
I am a chemist and a foodie but I had to look this one up!. The heating causes the formation of an iron sulfide, which while harmless, isn't as appealing as a nice bright yellow boiled yolk!.

From whatscookingamerica!.net

Watch the time when cooking the eggs carefully!. Overcooking causes a green layer to form around the yolk!. This layer is caused by a reaction between the iron in the yolk and the sulfur in the white!. Heat speeds up this reaction, so the longer your eggs cook, the greater the chance of discoloration!.Www@FoodAQ@Com

Its because of the sulfer in the eggs!. It reacts with the other minerals and coats the yellow with black!.

If you want beautiful, bright yellow yolks in your hard boiled eggs!. Do this!.

Put cold water in the pot, about 2 tablespoons of salt and tablespoon of white vinegar!. Put the eggs in the pot and make sure the cold water covers the eggs!. Put on high heat and bring to a rolling boil!. Let boil about 30 seconds to one minute!. Then take the pot completely off the heat and cover the pot!. Let the pot sit covered for twenty minutes!. Then rinse the eggs in ice cold water!. Peel immediately!. Those yolks will be bright yellow!.Www@FoodAQ@Com

It comes from not cooling straight away, I think the yolk releases something!.

Even if you if you are going to eat them out of the shell it pays to halt the cooking process by running under cold water for about a minute!.
They will still be warm to eat!.Www@FoodAQ@Com

No it is just over cooked!. Don't boil for as long!.Www@FoodAQ@Com

I never ever had that happen even when i overboiled i would say it is bad na dunno i looked online no infoWww@FoodAQ@Com

I wouldn't eat it if I were youWww@FoodAQ@Com





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