The variables that have an impact on the freshness of an egg include:
- how recently it was laid
- the temperature at which it was held
- the humidity and the handling
Pace Farm eggs reach most supermarkets within a few days of being laid. If the market and buyer handle the eggs properly, they will retain their freshness when they reach the table.
Because of the porous shell, an egg's characteristics will change over time. Air is absorbed and moisture is lost. This process is accelerated if eggs are stored in warm conditions as the pores expand making the transfer of moisture and air more rapid.
Over time the egg will change and the aircell found at the blunt end of the egg will grow larger.
Ideal storage conditions will maintain a constant cool temperature that does not exceed 4ºc and a relative humidity of between 70-80%. Eggs stored under such conditions will have a much longer shelf life.
testing the freshness of your eggs
To easily test the freshness of your eggs place an egg in a bowl of water. Fresh eggs will generally stay at the bottom of the basin as they only contain a small amount of air. Older eggs will stand on one end or float as the air cell has grown in size and is lighter than the surrounding water.
Another way to check is to crack open an egg and examine it - this is called a "break-out" test. Fresh eggs will have a smaller, tighter and more rounded yolk and the egg white will hold together with a thicker gel-like consistency.
On older egg will have a flatter and larger yolk, and the egg white will be thinner and spread further when broken.
Very stale eggs will develop a distinctive odour and flavour.