Eggs

Eggs are one of the most versatile and valuable of foods; rich in vitamins and minerals, they can be served as a main dish or used to thicken sauces, raise meringues and souffl�s, glaze sauces or set custards and batters.

Colour

The shells of chicken eggs may vary in colour depending on the breed of the hen; although many people think that that brown eggs are somehow better than white, there is no difference in quality or nutritional value of the egg contents.

Sizes

Hen's eggs are graded according to their size; the common sizes and their best uses are shown in the table below. It's worth bearing in mind that whenever a recipe simply calls for an egg, it is assumed that a medium sized variety will be used.

Size	Weight	Uses
Small (S)	Less than 53g	Glazing, thickening sauces, binding and stuffing.
Medium (M)	53-63g	Use for most recipes.
Large (L)	63-73g	Boiling, frying, poaching, scrambling, omelettes.
Very Large (XL)	Over 73g	Boiling, frying, poaching, scrambling, omelettes.

Freshness

The best egg, white or brown, small or large, is one that has been freshly laid by a free-range hen, so always check the date on the box.

As eggs begin to age, their membranes weaken and the flavour changes. The yolk of a fresh egg is tight and round when the egg is cracked into a pan, becoming flatter and more fragile as it ages. Egg white is thick when fresh and runnier and thinner when it is less so. The air space in the rounded end of the egg becomes increasingly large as the egg gets older and loses moisture; one way to test an egg's freshness is to immerse it horizontally in cold water:

If it sinks to a horizontal position, it is very fresh
If it tilts up, it could be up to a week old
If it floats into a vertical position, then it is stale

Safety

Research has shown that there is some risk of food poisoning by salmonella bacteria from eating raw or lightly cooked eggs (especially the yolks). It is therefore recommended that the elderly, pregnant women, infants and those with compromised immune systems avoid raw or partially cooked eggs.

Other Types of Eggs

Although the majority of the eggs we eat come from hens, there are also a variety of other types of eggs available for food preparation.

Duck Eggs

Duck eggs are larger than chicken eggs, with somewhat gelatinous whites and an extremely rich flavour. They are good to eat on their own, but are best when used in custards, mousses and other puddings. As they are larger than hen's eggs they need to be cooked for longer; for example, for boiled eggs, boil for at least 15 minutes to ensure they are cooked right through.

Goose Eggs

Goose eggs are also rich and make excellent omelettes, custards and mousses.

Ostrich Eggs

Although not readily available these days, ostrich eggs are said to be very tasty. One ostrich egg is equal to two dozen hen's eggs. An ostrich egg can make omelettes for ten people, and takes forty-five minutes of boiling to cook through.

Quail Eggs

Quail's eggs are much smaller than chicken eggs, and come in an attractive deep blue and brown speckled shell. They have a high proportion of egg yolk to white, and are particularly good when hard-boiled, fried or poached and served on toast or added to salads.