Have you ever boiled eggs, cut them open, and noticed a grayish-green ring around the yolk? Many people think it means the egg is spoiled — but it’s actually completely normal and harmless.
Why It Happens
The green ring forms when eggs are boiled for too long or at too high a temperature.
Here’s the simple science:
- The egg white contains sulfur
- The yolk contains iron
- When overheated, the sulfur and iron react and create a harmless green-gray layer
It doesn’t affect the taste or safety — it’s just a sign of overcooking.
How to Prevent It
You can easily stop the green ring by cooking eggs gently:
- Place eggs in a pot and cover with cold water.
- Bring to a boil.
- As soon as it boils, turn off the heat.
- Cover and let the eggs sit for 10–12 minutes.
- Move them into cold water immediately.
This method gives you bright yellow yolks every time.
Good to Know
The eggs are still perfectly safe to eat.
The color change is natural — not a sign of spoilage.