A fresh egg placed in a bowl of water will sink to the bottom, while an egg that is no longer fresh will remain on the surface. This is due to the evaporation of moisture and the increase of air in the egg’s air chamber as it ages. However, an egg that floats can still be consumed. The same is true for eggs that have passed their best before date.
This date indicates how long an egg retains its Grade A quality. Though an egg eaten after this date is less fresh, it has not lost its nutritional qualities. Use these eggs for recipes instead.