Flour

Flour (also called bur) is powder obtained by grinding the seeds of grains such as wheat, maize, rice, and millet, or other crops such as sorghum, beans, and cassava. It is the basic ingredient in bread, injera, pasta, biscuits, and many cooked or baked foods.

The most widely used flour in the world is made from wheat. This is because wheat contains a particular protein that, when mixed with water, forms a network called gluten. This network traps gas produced by yeast during fermentation, which is why wheat bread rises.

Production method

The seeds are first cleaned to remove dirt, small stones, and other material. They are then lightly crushed to make it easier for the outer layer (bran) to separate. Grinding is done using stone millstones (the traditional method) or rotating metal rollers (the modern industrial method). After grinding, the flour is sifted to separate the components: the outer bran, the endosperm (the starch-rich part), and the small germ.

Types

White flour is made by removing the bran and germ, and has a long shelf life. Wholemeal flour contains all the components, so it has more fiber and fat, but can go rancid more quickly. There are also gluten-free flours made from rice, maize, sorghum, or cassava, used by those who cannot tolerate gluten.

Nutrition and fortification

Flour is primarily composed of carbohydrates (starch), but also contains protein, fiber, and minerals. Many countries legally require that flour be fortified with minerals and vitamins such as iron, folic acid, and B vitamins, to prevent malnutrition-related diseases. This practice is called fortification.

Economics and use

Wheat flour is a global commodity traded extensively; its price depends on world wheat market prices and transport costs. In Somalia and many other East African countries, a large proportion of flour consumed is imported, and is used to make bread, injera, sabayad, and soup.