Rice is the staple food of more than 60 per cent of the world’s population. About 90 per cent of all rice grown in the world is produced and consumed in the Asian region (southeastern Asia). The protein content of milled rice is usually 6 to 7 per cent. Rice grain also contains as much Vitamin B as contained in wheat. Milled rice looses valuable proteins, Vitamins and minerals in the milling process, during which the embryo and aleurone layer are removed. Much of the loss of nutrients can be avoided through parboiling process, in which paddy is soaked in hot water and then dried in sun light for keeping moisture up to 14 per cent and milled. Steam paddy is known as parboiling.

The by-products of rice milling are used for a variety of purposes. Rice bran is used as cattle and poultry feed. Rice hulls can be used in manufacture of insulation materials, cement, and cardboard and are also used as litter in poultry keeping. Rice straw can be used as cattle feed as well as litter during winter, manufacturing of mat rope and for covering the thatched houses.

Hull: The lemma and palea together are known as hull. The grain is tightly enclosed by the lemma and palea.