Rice is possibly the grain that has been cultivated for a longer time and more extensively, occupying approximately 9% of the total arable land and is the second cereal in importance for human nutrition, after wheat. It is currently the food base of two-thirds of the world’s population.
Grinding in rice differs completely from that of wheat. Wheat is milled to obtain flour, while rice grinding includes husking, bran removal and finally separation of broken and damaged grains.
Rice from the field is the whole, known worldwide as “paddy” or paddy rice; contains fibrous and inedible outer shell called husk (glumes and glumes). When the peel is removed, but the pericarp (the bran) and the germ are preserved, brown rice is obtained, which after polishing is transformed into white rice. Rice is produced only for human consumption as a feed.
The most important quality criteria for rice are the grinding efficiency, the appearance of the raw grain, the cooking behavior and the texture and aroma of the cooked grain. The milling yield is a measure of the proportion of unbroken whole grains and reflects the variety, conditions of cultivation, harvesting and subsequent management. In the appearance of the raw grain the biometry (dimensions and shape of the grain), the color and characteristics of the pearl (dark areas of the grain, without crystallinity) participate.