The Incredible Expanding Rice

• Rice is a grain that's very rich in starch. While soaking rice in room-temperature water won't do anything to it, when the water is heated, the starch molecules within the rice are disrupted so that they expand and absorb the water around them. Each 1 part of rice will fully absorb 2 parts of water by volume before the rice grains stop absorbing liquid. This means that 1 cup of raw rice will absorb 2 cups of water when heated, resulting in 3 cups of cooked rice. By absorbing all this liquid, the rice will double in weight, so that 1 pound of uncooked rice will result in 2 pounds of cooked rice.

All Types of Rice Are Not Created Equal

• While most types of rice need 2 parts of water to cook 1 part of rice, both short- and medium-grain white rice require only 1 1/2 parts water to 1 part rice. Arborio rice calls for the most water, requiring 4 1/2 parts water to cook 1 part rice. When cooked, all types of rice triple in volume but instant rice only doubles in volume. Instant rice, unlike other types of rice, is actually precooked in water and then dehydrated. The precooking greatly reduces the cooking time to only around five minutes. Because it's already cooked, the rice only requires an equal part water to prepare.

Timing Is Everything

• Most types of rice will cook within 20 to 30 minutes when simmered on the stove, although brown long-grain or wild rice may take between 40 and 50 minutes to cook. After the rice is fully cooked, it may begin to burn and harden if you've left it on the burner. Rice that's cooked in more liquid than it will absorb and left to simmer for longer than its recommended cooking time becomes mushy. To prevent problems with over- or undercooking your rice, you can use a rice cooker, which senses when the liquid in the pot has evaporated and switches to a warming setting that won't dry out the rice when it's done.

Keeping It All Fresh

• Not only does rice change in size and weight when cooked, but the way that you store it changes as well. Uncooked rice stored in a pantry can last from five to 30 years in an airtight container, although brown rice only lasts for up to eight months. Once any rice is cooked, though, it can quickly spoil and you must refrigerate it at 40 degrees Fahrenheit or below. Cooked rice has a shelf life of around one week in the refrigerator when stored in an airtight container. When reheating your rice, add a small amount of water to it and cover it to keep it moist.