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Rice Science

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Potato Basmati Rice Casserole

Potato Basmati Rice Casserole

Linda Larsen
How many times have you put a pot of rice on to simmer, and come back to it 20 minutes later to find a sticky, gluey mass of rice? Learn about the different types of rice, and what happens inside the grains during different cooking methods.

There are many different varieties of rice. They differ in amounts of nutrition and, more importantly, the type of starch. There are two types of starch in rice: amylose and amylopectin. Amylose is a long, straight starch molecule that does not gelatinize during cooking (think of making gelatin), so rice which contains more of this starch tends to cook fluffy, with separate grains. Long grain white rice has the most amylose and the least amylopectin, so it tends to be the fluffiest and least sticky. Amylose also hardens more when cool, joining tightly together and forming crystals that melt when the rice is reheated. Rice that is high in amylose has a lower Glycemic Index number.

Amylopectin is a highly branched molecule that makes the rice sticky when it's released from the grain during cooking. Medium grain rice has more amylopectin, making it a good candidate for risottos, salads and rice pudding, which are served cold. And short grain rice has even more amylopectin and little to no amylose, so it's used most often for Asian cooking, when you want grains to be sticky so they are easier to eat with chopsticks. Then there's glutinous rice, which is very sticky when cooked, with the highest amount of amylopectin and no amylose.

White rice has the hull and bran removed, diminishing its nutritional content. But in the U.S., rice is generally enriched, with nutrients like calcium, riboflavin, iron, and niacin added. Brown rice has just the hull removed, so it has more fiber and nutrition. Converted rice is boiled or steamed before it is processed, which forces some vitamins and minerals into the kernel from the bran. Converted rice is higher in nutrients than plain white rice. And wild rice is not a grain, but a seed of a grass native to North America.

When rice cooks, the heat and liquid start permeating the surface of the rice. The starch molecules inside the rice grains start breaking down and absorb water to form a gel. The type of starch in the rice determines whether it will be fluffy or sticky.

Rice Types

  • Long Grain White Rice
    Cooks up fluffy and separate. Less fiber, but usually enriched with nutrients, vitamins and minerals.
  • Medium Grain Rice
    More amylopectin in the grains and a softer outer layer, so it releases starch during cooking and cooks up creamy.
  • Short Grain Rice
    More amylopectin in the grains; releases lots of starch during cooking; sticky and creamy when cooked.
  • Brown Rice
    Only the hull is removed during processing; the bran is retained, resulting in more fiber and nutrients. Takes longer to cook than white rice because the outer layer is harder.
  • Basmati Rice
    Long grain rice, aromatic (smells like popcorn when cooking), cooks up fluffy and separate.
  • Wehani Rice
    Long grain, unpolished brown rice, with a very sweet flavor. Cooks up fluffy and separate.
  • Jasmine Rice
    Long grain and aromatic, but with more amylopectin than regular long grain rice, so it cooks up creamier than long grain.
  • Arborio Rice
    Short grain rice usually used for risotto. It releases lots of amylopectin during cooking, so the finished dish is creamy and has a great soft mouth-feel.
  • Wild Rice
    The seed of a native grass, this 'rice' takes longer to cook than brown rice and has a nutty flavor and chewy texture. It cooks up fluffy and separate, unless you cook it until it 'pops', or the outer covering disintegrates. Then the rice is softer and less separate.
  • Converted Rice
    This is rice that has been partially precooked, then dried, so it cooks more quickly. It's a good choice if you aren't picky about your rice quality; you are also guaranteed consistent results. Instant Rice is even more processed; you just rehydrate it by adding it to hot water and letting it stand, covered, until tender.

Go to the next page to learn how to cook rice.

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