How to Tell if Eggs Are Still Okay to Eat Without Cracking the Shell
- 1). Fill a bowl or pan with cold water. Add a small amount of salt and then stir to dissolve the salt. Submerge one or more eggs in the salted water and watch for the results. For quicker testing, do only a few at a time.
- 2). Observe what happens as you place each egg in the water. A small air pocket is located in the large end of an egg. This pocket is extremely thin and only about as large as a dime in fresh eggs. Older eggs lose moisture and carbon dioxide as they age, increasing the size of the air space. This air space determines the buoyancy of the egg.
- 3). Watch to see if the submerged egg sinks to the bottom and lies flat on its side. If this occurs, the egg is fresh. Eggs that are at least a week old will sink to the bottom too, but will bob slightly in the water. Eggs older than three weeks will sink, but will balance on the small end with the larger end pointing up. Bad eggs will only float.
- 4). Check for freshness of eggs by holding them up to a light if you are still unsure after the floating test. Dealers often use this method. Use a flashlight or other small light in a darkened room to look for the presence of dark spots inside the egg. These spots occur when the air space between the shell and the lining membrane fills up. Fresh eggs are translucent while older eggs are not. Older eggs will tend to adhere to the shell on one side. Fresh eggs weigh more than older ones, because they have less air space.
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