Not sure if your eggs are fresh? Try these foolproof tests before whisking up your next omelette.

There's no question that the best egg is a fresh egg - anything less won't respond well to cooking. Yet, when it comes to identifying a fresh egg, so many of us are at a loss

The easiest way to tell if you've got a good egg is to float it in a cup of water. A fresh egg will sink in water; a stale one will float. The reason a stale egg will float is that a considerable amount of its contents have evaporated. This enlarges the air sac at the blunt end of the egg, giving it buoyancy.

Once you've cracked your eggs, compare the size of the yolk to the size of the white. Stale eggs have thin, watery whites and large flat yolks, compared to the compact yolk of a fresh egg (see diagram below). Also, the rope-like protein strands holding the yolk in place should be firmly attached, not floating around in the white. If you break the egg into a transparent bowl, then hold it at eye level, you'll see two very distinct layers of white. That's a fresh egg!




Stale eggs have a watery eggwhite and large, flat yolk.
Fresh eggs have a compact yolk and thick eggwhite.
Another telltale sign that an egg is stale is if the yolk breaks in the pan. It's surprising the number of people who think the poor fried or poached eggs they've produced are the result of their bad cooking, when in fact the egg is stale.

Don't worry about the yolk colour - despite popular belief, the colour of the yolk has no bearing on the egg's quality. Pale yolks are just as nutritious as dark yolks. Colour is influenced by what hens eat. Hens on diets containing maize and lucerne lay eggs with dark yolks, while hens on wheat-based diets will lay large eggs with pale yolks.

Another misconception is that stale eggs and rotten eggs are the same thing. They're not. The difference is, rotten eggs have been affected by bacteria and/or fungi. Eating a stale egg won't harm you but eating a rotten egg can give you food poisoning. However, thanks to quality-assurance schemes, only very rarely does a rotten egg find its way into the marketplace. Stale eggs, on the other hand, are a persistent problem and while they won't make you sick, they will prove difficult to cook. Besides knowing the difference between a fresh and stale egg, it's important to know how to handle your eggs once you get them home.

At home, put eggs in the refrigerator straight away. If you leave them out for any longer than 24 hours their chemistry will change permanently and for the worse. In fact, to keep them at their best, eggs should be refrigerated from the time they're laid until you're ready to cook them.


Cooking tips

- Boiled eggs
Before cooking, wash eggs in warm water to bring them to room temperature. Boil in lightly salted water for 3 minutes for soft yolks or 5 minutes for firm yolks.
- Scrambled eggs
For extra-fluffy scrambled eggs, add a little water when you're beating them.
- Poached eggs
Transfer eggs to a non-stick pan containing about 10cm of simmering, lightly salted water. Stir water with a spoon, then drop egg in centre. Cook for 3-4 minutes. To reheat, slip egg onto a slotted spoon and hold in simmering water for 1 minute.