When an Egg Floats on Top of Water, Is it Not Good to Eat?

Fresh Eggs in an Egg Carton Fresh eggs usually don\’t float in water. Image Credit: Eising/Digital Vision/Getty Images

When an egg floats, it's because a small air pocket inside the shell has had enough time to expand sufficiently to make the egg buoyant. Floating can be a sign an egg isn't as fresh as you might want it to be, but it takes closer inspection to determine whether the egg is spoiled. It all depends on time and the eggshell.

Video of the Day

Porous Eggshells

Eggshells look solid, but in reality they're rather porous. After a hen lays an egg, fluid evaporates through microscopic holes in the shell and air seeps in as the egg cools. The air collects in a pocket at one end. As the egg ages and takes in more air, this air pocket expands and eventually gives the egg enough buoyancy to float in water.

Dunking for Freshness

Placing eggs in water to test their freshness is an old technique. Using a spoon, you lower the eggs into a bowl or pan of cold, unsalted water. The freshest eggs will sit on the bottom of the container. Some eggs will tilt upward, indicating they have more air inside and are older. Other eggs will stand up on the point end; these eggs usually are still safe but are better used to make hard-cooked eggs or in baking.

The Nose Knows Rotten Eggs

Eggs that float to the top are often considered spoiled because more air has seeped in through the shell and decomposition may have started. Decomposition, or spoiling, produces sulfur gas, the cause of the "rotten egg" smell. There's only one sure way to tell if an egg that floats is spoiled, and that's to crack it open in a bowl. If it smells bad and looks discolored, throw it out. If it looks and smells fresh, you can use it for cooking or baking.

Take Extra Care with Eggs

Eggs need careful handling and storage because their shells can harbor salmonella bacteria. More than 2,300 different varieties of salmonella can exist on eggshells. Because low temperatures inhibit salmonella growth, the USDA and the American Egg Board both recommend eggs in their cartons be refrigerated at temperatures between 33 and 40 degrees Fahrenheit. This keeps them outside the "danger zone" between 40 and 140 F, where bacteria grow fastest. Eggs left out at room temperature should be discarded after two hours, or after one hour if the room is especially warm.

Related Stories

Discover

Caught in the Middle

Caught in the MiddleHelp for the Sandwich Generation- Twenty million American adults are caring for aging parents at the same time they\'re raising young children. Known as the Sandwich Generation, the

The Importance of Senior Fitness

The Importance of Senior Fitness- According to the National Institutes of Health (NIH), exercise and physical activity are some of the best things older adults can do to stay healthy. Even moderate ex

Grandparent Getaways

Grandparent GetawaysTrips to take with your grandchildren- \"No parents allowed.\" It\'s not a sign on a kid-only clubhouse, it\'s the first rule of travel for memory-making grandparent/grandchild vacatio

Comfortably Aging in Place

Comfortably Aging in PlaceHaving lived in the same ranch house for 55 years, John Heck’s grandparents wanted to make any and all necessary accommodations to allow them to peacefully age in place. Usin

Aging with Vitality, Grace and Confidence

Aging with Vitality, Grace and ConfidenceIt’s one of the great ironies of life: Your reward for surviving the tumultuous teen years, establishing a career and nurturing a family culminates in dry skin

3 Ways Seniors Can Control Prescription Costs

3 Ways Seniors Can Control Prescription CostsFor 55 million Americans enrolled in Medicare, the New Year means any new Medicare Advantage or prescription drug plans, or any changes to your existing pl

Popular Categories