Understanding the blue ring in boiled eggs: Causes and safety

The unsightly, likely doubt-inducing bluish ring around the cooked yolk is not dangerous. It simply means that we boiled the eggs incorrectly.

Have you ever noticed an unattractive, bluish ring around the cooked yolk? The reason for its appearance is simple and results from boiling the eggs for too long. Beyond 10 minutes, a chemical process occurs, during which two elements precipitate from the yolk: sulfur and iron. These two elements combine to form a chemical compound called iron sulfide, which is responsible for the unattractive, bluish color.

However, you don't need to worry - an egg with a bluish ring is completely safe to eat. The color change is only an aesthetic defect that might affect the visual experience but has no impact on the egg's taste or its safety for health.

It is worth noting that boiling for too long, besides the unwanted change in yolk color, has another negative effect - it leads to the loss of valuable nutrients contained in the eggs. However, if you do not like soft or semi-soft eggs, there is no reason not to continue your current method of preparation. Hard-boiled eggs should be cooked for about 7-8 minutes from the moment the water starts boiling. This ensures that the yolk retains its beautiful, sunny color. After boiling, pour cold water over the eggs to stop the cooking process.

To the pot in which you boil the eggs, you can add 2-3 tablespoons of salt or a few slices of lemon. This simple trick will make peeling the shell easier later on. Similarly, adding baking soda to the water works. After boiling, gently tap the eggs against the edge of the pot or kitchen counter so that the shell cracks slightly. Once the eggs cool down, you can start peeling.