Flour from wheat is the most versatile and there are many different types. although there are flours made from other cereal grains, such as spelt and maize.
Plain flour has had almost all of the bran and wheatgerm removed. It is a good all-rounder and can be used for making cakes and biscuits, batter and as a thickener in sauces and stews. It is usually sifted with a raising agent like baking powder or bicarbonate of soda when baking cakes.
Self-raising flour is plain flour mixed with baking powder. It has a more limited shelf life than other flours because the baking powder absorbs moisture and in time, will lose its raising power. It can be substituted by mixing plain flour and baking powder together (add 4 teaspoons of baking powder to every 250g plain flour).
Strong flour is used for making bread and is made from 'hard' wheat varieties that are rich in gluten. Gluten gives bread dough its elasticity, allowing it to stretch and rise, resulting in a light loaf.
Italian 00 flour is now more in demand in the UK with keen cooks turning their hand to making pasta at home. It is extremely finely milled flour with varying levels of gluten, used for making pasta and pizza or baking cakes and biscuits.
Wholemeal flour is more nutritious than white flour because the bran and germ are not removed during milling. It is usually used in combination with strong flour when baking bread to help keep the loaf light.
Store in a cool dry place, preferably in an airtight container and use any opened packets within one year.