What Causes the Green Ring?
The greenish-gray discoloration around the yolk occurs due to a chemical reaction between sulfur in the egg white and iron in the yolk. When eggs are overcooked or boiled at too high a temperature:
- Sulfur compounds in the egg white break down and release hydrogen sulfide gas.
- This gas reacts with iron in the yolk to form ferrous sulfide , which creates the greenish ring.
