The developments in commercial rice milling technology has had strong contributions from the private sector. Recent developments have virtually replaced the old stone disk huller; vertical cone polishers with rubber brakes known as rubber roll huskers; the abrasive emery coated-cylinder and friction type whitener-polisher; the German Schule patented whitening machines; and the dry or wet mist polishers. Other mill components are standard with innovations added by each manufacturer. New plants are increasingly becoming automated to minimize operator judgement. There are well known manufacturers whose machines are found in Asia such as Satake, Nippon Sharyo, Iseki, and Kyowa of Japan; Schule and Miag of Germany; Rice Engineering of Thailand. It is also possible to find rice milling machines from Italy, France, and the UK although we are unfamiliar with them. There are also local manufacturers in most Asian countries.
The big variables in the performance of rice mills are quality of paddy, maintenance of the machines, and operator skill. Dwayne Sutter (Texas A & M) says that mixing varieties with different sizes does not allow for proper machine settings. He further observed that many mill owners do not supervise and train their operators. They do not recognize that higher yields could be obtained if the rice mill was properly operated.
The single pass, cylindrical ribbed iron rotor with an adjustable hulling blade and lower screen concave is a rice mill noted for its robustness and poor head rice yield. The first models found in Asia were the Engleberg models from the US and the Lewis C Grant model from the UK. Now most of the countries in Asia produce rice mills. The performance of these mills is covered in further detail in the section on milling losses.