More than two thousand varieties of rice are grown throughout
the world. The International Rice Research Institute (IRRI) in the Philippines
holds more than 83,000 varieties in its gene bank. The differences are
related to morphology of the plants and grains, resistance to falling,
precocity, ramification, productivity, as well as resistance and tolerance
of biotic factors (weeds, diseases and insects) and non-biotic factors
(cold, drought, soil acidity, lack of mineral components, etc).
Any irregularity (yellow or chalky kernels and foreign matter) reduces the rice quality grade.
- Long grain rice kernels are 3 times longer than they are
wide (more than 6 mm). When cooked, this grain is light and separates
easily. There are also glutinous long grain rices in Laos and Thailand.
Brown rice (husked rice)
Paddy from which only the external and non-edible husk has been removed. The bran layer remains, making it more nutritive than white rice. In Europe, this type of rice is often called "cargo rice" because of the way it is transported by sea. Frequently green kernels are found with the brown rice as grain maturation is not homogeneous. In addition, more than one variety may be planted in the same field. Separating the grains before or after harvesting is difficult and expensive. There are also green grains in the white rice, but they are less visible because of the more intensive husking process.
Milled and polished kernel which loses many of its nutrients when the outer layer (the husk and bran layer) is removed. It contains much less niacin, thiamin, magnesium, zinc, iron and fiber than the brown rice. In some countries, including the United States, white rice may be enriched with iron, niacine and thiamine so that it can reclaim part of its original nutritive value. White rice may be covered with magnesium silicate or with a mixture consisting of talc and glucose (also known as "talc-coated rice").
Red rice has a red bran covering the kernel (Himalayan,
Bhoutanais or Thai).
Arborio rice is a white and round grain, considered
one of the finest rices because it can absorb a high quantity of liquid
while cooking, without becoming soggy.
For detailed information on rice´s