Eggs are a major ingredient in many dishes, and may be used whole or separated in yolk and white, to take advantage of their individual qualities.
The majority of eggs sold in Great Britain have brown or white shells, although pale blue, greenish-blue, pink, speckled and other shells are increasingly being seen. The colour has no bearing on either the taste or nutritional value, but is just due to the breed of the hen. Yolks can also vary in colour, from pale yellow to a much deeper shade. Many yolks are dyed a uniform colour by adding colouring to the hens' feed.
Most eggs will keep for up to three weeks, stored in the refrigerator in their box. Very fresh eggs are best for poaching and frying, while for hard-boiling it's better to use eggs 1-2 weeks old.
There are many basic ways to cook eggs. To boil, use eggs at room temperature if possible. Put the egg into a pan of barely simmering water, bring back to a simmer and cook to taste: depending on size allow 3-4 minutes for soft yolks, 5 minutes for medium and 8-10 minutes for hard (quail's eggs take 2-3 minutes less than this; duck eggs will take a minute or so longer and goose eggs 4-5 minutes longer).
To poach, if the eggs are not very fresh, add a few drops of vinegar to a wide pan of simmering water. Crack open the egg and slide it in, then cook for 4-5 minutes.
To fry, crack the egg into a pan containing hot oil or melted butter and cook for 4-6 minutes.
To scramble, lightly beat two or three eggs together with a few spoonfuls of milk or cream and some seasoning, then cook gently in melted butter, stirring to 'scramble', until softly set.