Most of the researches on rice whitener con-ducted so far dealt mainly with the japonica or short-grained rice varieties. Matsuda8) studied the whitening characteristics and the opera-tional conditions involved in using a horizontal rice whitener. Kawamura5) conducted a basic study on the elastic behavior of whitening rice grain and the whitening pressure developed in a horizontal rice whitener.
By using the advanced rice-processing technology, a new type of rice whitening set with low operation pressure and light temperature increase was developed to provide a optimum solution for the rice processing in South China. The key techniques involved in the design include the set layout featured with the combination of light abrasive pearling, light friction pearling and light polishing and the innovative design of the fiction whitener. In the whitener design, a roller with a big ratio of length to radius and an olive geometry, which matches with the screen to form two special frustum chambers, was applied so that the functions of whitening, polishing and brushing were integrated. The new set has some advantages such as low broken rate, high rice yield, low power consumption and high quality rice surface.
Modern and traditional premilling, milling, and postmilling processing of different rice
types is comprehensively reviewed. The implication of industrial rice processing methods, especially rice destoner, as well as techniques for nutrient extraction, transfer, and enhancement, such as rice parboiling, sprouting, and fortification, for the degrees of macro- and micronutrient content, stability, and retention, and consumer preferences, are documented. Socioeconomic constraints facing various aspects of rice processing are also discussed.