Rice is a staple food for at least 2/3 of the world's population. However, there are so many different types of rice that it could get a bit confusing.
Here’s a bit of an overview.
Rice is a member of the grass family. The plant is native to tropical and subtropical southern Asia and Southeastern Africa.
There are different types of rice, categorized based on processing, size and variety.
Brown rice undergoes the least amount of processing. The first step in milling of the rice plant is the removal of the outer husk and the product after this step is brown rice. The bran stays intact therefore brown rice contains more nutrients and 4 times the fibre found in white rice.
The Glycemic Index (GI) is a scale that ranks foods by how much they raise blood glucose compared to a standard food. A glycemic index off 55 or below is considered low and 70 or above is high. Brown rice falls in between with a GI of ~66.
Converted or Parboiled rice has been soaked and then steamed under pressure before milling. This actually forces some of the nutrients into the remaining portion of the grain so that some are retained during processing. As a result, this rice falls between brown and white rice in terms of nutrient content but actually has the lowest GI with a GI of 48.
Enriched rice has had the B vitamins (thiamin, niacin) and iron added after milling to replace some of the nutrients lost when the bran layer is removed.
Instant white rice has been milled and polished, fully cooked and then dehydrated. It is usually enriched but does not have the superior taste and texture of regular rice.
Long-grain rice is four to five times longer than it is wide. When cooked the grains are fluffy and dry and stay separated. It’s ideal for salads. Long-grain rice (unconverted) has a medium GI of ~57.
Medium-grain rice is about twice as long as it is wide and cooks up moister and more tender than long-grain. It is popular in some Asian and Latin American cultures, and is the type of rice most commonly processed to make cold cereals.
Short-grain rice is oval or round in shape. Of the three types of rice, it has the most starch that makes it sticky, or clump together, when cooked. It is ideal for dishes such as sushi. Short grain rice has a high GI of >70.
Arborio: A starchy white rice, almost round in shape. Traditionally used for cooking Italian risotto. It also works well for paella and rice pudding. Arborio absorbs up to five times its weight in liquid that results in grains of a creamy consistency. This type of rice has a high GI of ~70.
Aromatic rice: Primarily long-grain varieties that have a toasty, nutty fragrance
Basmati: The most famous aromatic rice is grown in India and Pakistan. The grains elongate much more than they plump as they cook. Can be substituted for regular white rice in any recipe. You can also purchase brown basmati rice. Basmati rice is a long-grain variety. Basmati rice has a medium GI of 58.
Glutinous, sticky or sweet rice: Long-grain rice with a very high starch content. Suitable for Chinese dishes of shaped rice, such as rice balls or sticky rice cakes. This type of rice has a very high GI of ~98.
Jasmine, perfumed or Thai fragrant: A traditional long-grain white rice grown in Thailand. It has a soft texture and is similar in flavour to basmati rice. It is also grown in the United States where it is available in both white and brown forms. Jasmine rice has a very high GI of ~109.
Foster-Powell, K; Holt, S; Brand-Miller, JC. International table of glycemic index and glycemic load values. American Journal of Clinical Nutrition. 76(1) 2002. http://www.diabetes.ca/files/Diabetes_GL_FINAL2_CPG03.pdf