BLUE SPRINGS, Mo. – Believe it or not, hard-cooked eggs can spoil faster than fresh eggs, so if your family plans to eat dyed Easter eggs, it’s important to follow food safety principles to prevent illness.

“Eggs are porous and bacteria can penetrate the shell. When they are washed at the plant, a protective coating is added,” said Tammy Roberts, University of Missouri Extension nutrition specialist.

But that protective coating is washed away during boiling. “It again becomes easier for bacteria to enter the shell,” Roberts said. “For this reason, it is important to refrigerate hard-cooked eggs within two hours of cooking. This means you’ll need to work quickly to get them dyed.”

However, if you see a green ring on your egg yolk, don’t be alarmed. “The green ring is a result of sulfur and iron compounds reacting on the surface of the yolk,” she said. “It may not look appetizing, but the eggs are completely safe and the taste is not affected.”

The green ring can occur when eggs are overcooked or when there is a high amount of iron in the cooking water. The American Egg Board has a recommendation for cooking tender eggs with no green ring:

Place the eggs in a single layer in a saucepan. Add enough water to cover the eggs by one inch. Cover and quickly bring just to boiling. Remove from heat, leaving the pan covered. Let sit for 15 minutes for large eggs, 13 minutes for medium eggs and 10 minutes for small eggs. Immediately run cold water over eggs until they are completely cooled.

If you don’t want to worry about the safety of the egg, you can carefully empty the shell and then dye it, Roberts said.

The first step is to wash and dry the egg. Next, prick the egg with a long needle to make a little hole at the small end of the egg and a bigger hole at the large end of the egg. Stick the needle deep into the egg to break the yolk. Then either shake the egg, large end down, over a bowl, or use a baster to pull out the contents. The contents can be used in any thoroughly cooked recipe that calls for mixed yolks and whites.

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