Greenish or dark eggs. This is not a sign of spoilage. It’s often due to the hen’s diet or the presence of a rare pigment called oocyanin. The eggs are safe to eat.
A ring around the yolk after hard-boiling. This happens when eggs are overcooked. The greenish-gray ring is a chemical reaction between the iron in the yolk and the sulfur in the egg white. It’s harmless but not very attractive.
What About Parasites in Eggs?
This is a common fear, and it’s understandable. The idea of eating something that might contain a parasite is genuinely unsettling.
Here’s the good news: eggs are remarkably safe.
The USDA and the FDA strictly regulate commercial eggs in the United States. All commercial eggs are washed, graded, and inspected. Parasites in eggs are extremely rare.
In the extremely unlikely event that a parasite were present, it would be killed by cooking. Eggs should always be cooked until both the white and the yolk are firm—not runny. This kills any potential bacteria and parasites.
