Eggs

Eggs are a staple in most kitchens. We reach for them when there's nothing else in the fridge or when an unexpected guest drops by at dinner time and we need to add an extra dish to the planned meal.

Types: when we think of eggs, we automatically think of those from chickens, but all birds lay eggs. Insects, fish and most reptiles also produce eggs but we'll stick to the chicken variety for this column.

What to look for: for flavour, fresh is best. When broken into a pan, fresh eggs stay more compact - the white is thicker and the yolk stays round, rather than flattening out. The air sac (at the large end of the egg) is smaller in fresher eggs. You can test for freshness by shaking the egg (the sloshing you feel inside should be minimal) or by standing the egg in a bowl of water: it should sink to the bottom and lie on its side; if it stands on its round end, or even worse, if it floats, it's not fresh. Examine eggs for any cracks in the shells, which can let in bacteria and germs.

Size: eggs come in small, medium, large and extra-large, which means they range in weight from about 500 grams a dozen (for small) to approximately 775 grams a dozen (for extra large). The size doesn't matter much for savoury preparations, but it can make a difference in patisserie. Most pastry recipes call for large eggs, but substituting extra large for large (or vice versa) doesn't affect results that much.

Colour: the most common are brown or white, although certain breeds of chickens lay beautifully coloured or speckled eggs. Brown eggs are thought to be more flavourful than white but that isn't necessarily true. Flavour is determined by what the chickens were fed and the freshness of the egg.

What else? Ostriches lay the largest eggs of all birds - more than 1.5kg.