Old Eggs Float Or Sink

Whether old eggs float or sink is a common kitchen question with a simple answer: old eggs float, while fresh eggs sink. This phenomenon is due to the changes that occur inside an egg as it ages.

When an egg is laid, it is filled with a thick, viscous substance called albumen (egg white) that surrounds the yolk. The yolk is held in place by a thin membrane called the chalazae. As the egg ages, the albumen gradually breaks down and becomes thinner and less viscous. This causes the yolk to become less dense and more buoyant, and eventually, it will float to the top of the egg.

In addition to the changes in the albumen, the air cell inside the egg also plays a role in its buoyancy. As the egg ages, the air cell gradually increases in size. This is because the evaporation of water from the egg causes the air cell to expand. The larger air cell makes the egg more buoyant, which also contributes to its ability to float.

So, if you have an egg that you're not sure about, you can simply drop it into a glass of water. If it sinks, the egg is fresh. If it floats, the egg is old and should be discarded.

Other Factors that Affect Egg Buoyancy

The age of an egg is not the only factor that affects its buoyancy. Other factors include:

Egg size: Larger eggs tend to float more easily than smaller eggs because they have a larger air cell.
Egg temperature: Warm eggs float more easily than cold eggs because the air cell expands when the egg is heated.
Water temperature: Cold water is denser than warm water, so eggs float more easily in cold water.
Salt concentration: The addition of salt to water increases its density, which makes it more difficult for eggs to float.

How to Use the Egg Float Test

The egg float test is a simple way to determine the freshness of an egg. To perform the test, simply follow these steps:

1. Fill a glass or bowl with cold water. 2. Carefully drop the egg into the water. 3. Observe whether the egg sinks or floats.

If the egg sinks, it is fresh and can be eaten. If the egg floats, it is old and should be discarded.

Safety Precautions

It is important to note that the egg float test is not a foolproof method for determining the safety of an egg. Even if an egg sinks in water, it may still be unsafe to eat if it has been contaminated with bacteria. Therefore, it is always important to cook eggs thoroughly before eating them.