A valuable food grain and the staple food of many countries. There are many varieties, the most common being triticum aestirum or ‘bread wheat’, which accounts for 90 per cent of the world’s production. This is refined into flour and used in baking or as a thickener. Triticum durum or ‘durum wheat’ is used in the production of dried pasta. A grain of wheat consists of an outer coating (bran), the embryo (wheat germ), and the endosperm, the floury part. During milling, the endosperm is ground into varying–sized particles to produce flour and semolina. Wheat is also made into burghul, puffed wheat (eaten as a breakfast cereal and used in confectionery), couscous and freekeh, used widely in Arabic cookery.