Why does a green ring appear around hard-boiled eggs?

 

The Science Behind the Green Egg Yolk

That greenish-gray ring around your hard-boiled egg yolk is a simple chemical reaction. It's completely safe to eat and is caused by overcooking.

The Cause:
When eggs are heated for too long or at too high a temperature, the sulfur in the egg white and the iron in the yolk react to form a new compound called ferrous sulfide—which is the greenish ring you see.

How to Prevent It:

1. Don't Overcook: After bringing your water to a boil, reduce it to a gentle simmer. Cook for 9-12 minutes for large eggs.

2. Cool Immediately: As soon as the eggs are done, plunge them into an ice water bath. This stops the cooking process and prevents the reaction.

While it might not look as appetizing, the green ring has no effect on the egg's taste or safety. It's just a sign to adjust your cooking time next time!