History of Rice
Rice is thought to be the oldest cultivated grain and has been a vital food source to billions of people spanning thousands of years. Its importance can be seen in the various ancient cultures that have relied on it. Chinese mythology states that rice was brought to the starving people by a dog and the grain was prized more than jade or pearls. In Burma and Bali rice was thought to be a gift from the gods. In Japan, the emperor was considered the living embodiment of the rice plant. Additionally, in several Asian languages the word for "rice" was the same word as "food" or "agriculture".
Rice was thought to be cultivated as early as 6000 BC and sealed pots of ancient rice have been found in China that are about 8000 years old. The exact origin of the rice plant is not known, but it is thought to have been originally cultivated in Southeast Asia around modern Thailand and China. Traders were responsible for spreading rice throughout the world. It spread first to the to the Philippines, then to Japan, and later to India. It reached Greece in 300 BC and was traded throughout the Mediterranean. Rice was initially not grown in Western Europe due to the threat of malaria. Rice plants grew best in flooded fields, yet the standing water also increased mosquito populations. The rice plants finally spread throughout Europe in the 1400s. The Spanish and Portuguese introduced rice to Central and South America and they also transported rice to South Carolina in the 1600s, where it spread to New Orleans and later to California.
Today, rice remains a vital source of food. It is a staple for about half of the world’s population and it is cultivated in more than a hundred countries around the world. More than ninety percent of all rice on the planet is grown and consumed in Asia. Trading and breeding has produced more than seven thousand varieties of rice.
Rice Plants
The term "rice" technically refers to the grain produced by the plant called "paddy" (Orzyza). There are over twenty different species of Orzyza, but there are only two main species that are cultivated: O. sativa and O. glaberrima. The former originated in Asia and is the most common while the latter is native to Africa. The plant is a tall grass that grows to be 2 to 18 feet tall. The plant produces a stalk that contains hundreds of tiny flowers that develop into grains. The time from planting to harvesting the rice is about 4 to 6 months, depending on the variety. The grains are threshed by hand or harvested by a combine. These grains are dried, processed, and then stored or sold. Rice can be stored for a very long period of time compared to other grains because it contains less water.
Rice plants are grown under one of two conditions. The first, called "upland" rice, is grown in soil that is not flooded. The original crops of rice are thought to have been grown this way. However, it was soon discovered that the rice plants grew faster and taller and produced a better grain if they were constantly submerged in about 4 to 8 inches of water. The rice plants are first germinated in drier soil and then planted in flooded fields, called paddies, to grow. The water is kept fresh by draining and reflooding or providing a continual influx and outflux of water. The discovery that rice grew better in flooded fields helped the crop spread throughout Asia.
The rice plant actually does not need all the water in the flooded field to survive. The water actually is a method of controlling weeds and insects that would stunt plant growth. The flooding also helps keep the land fertile because it prevents salt accumulation that can be unhealthy to vegetation. Additionally, the flooding creates a false wetland region where birds and other wildlife can live and it helps maintain a steady air temperature in the area.
Uses of Rice
Obviously, rice is mainly sold and consumed in its grain form. However, the grain can also be crushed into rice flour that is used to make bread, noodles, and other baked goods. The rice grain is also fermented to make rice wine (sake) or rice vinegar. Leftover hulls and bran from processing are used as livestock food.
Rice and rice flour are an excellent alternative to wheat and wheat flour for those with food allergies, since rice does not contain any gluten. Rice is full of nutrients such as magnesium, thiamine, niacin, phosphorus, vitamin B6, zinc and copper. Some varieties also contain iron, potassium and folic acid. Rice also contains a decent amount of protein.
jasstrong kindly reminds me about yellow rice, a genetically modified variety of rice that contains vitamin A. Check out the yellow rice node for more info.
Categorizing Rice
Rice comes in three sizes of grain length, long, medium, or short. Long grain rice is four to five times longer than it is wide, medium grain rice is about two to three times longer, and short grain rice (also called pearl or glutinous rice) is almost round. Long grain rice, such as basmati or jasmine rice, contains the lowest level of starch of the three and this keeps the cooked rice grains dry and separate. This kind of rice is commonly used in stir fries, fried rice, and curries. Medium grain rice has a medium amount of starch and is used in soups, stews, paella, and risotto. Short grain rice has the highest amount of starch which makes the cooked rice sticky and moist. This type is preferred in sushi, rice balls, and desserts.
Rice is also categorized as either brown or white rice depending on how the rice is milled. The rice grain is composed of the white endosperm surrounded by bran and germ and encased in an outer hull. Brown rice has this inedible hull removed during milling but the bran is left on, giving it the brown color. It is more nutritious than white rice and contains high levels of insoluble fiber and vitamins B and E. The bran gives brown rice a pleasant nutty flavor and a chewy texture. Brown rice takes about twice as long to cook as white rice and it has a shorter shelf life due to the oils in the bran that can turn rancid. It is best to keep brown rice in the refrigerator to increase its life span.
White rice has the bran, germ, and hull of the rice removed during the milling process. This removes the brown color and most of the nutrients found in brown rice. However, white rice often has these nutrients added back, making the rice "enriched." Enriched white rice actually contains more thiamine and iron than brown rice. It also has a longer shelf life. Both white and brown rice come in long, medium, or short grain varieties.
On top of that, rice may also be sold in its normal form, parboiled form, or instant form. Parboiled rice has been soaked and cooked before it was processed, which draws some of the nutrients from the bran into the endosperm of the rice. This makes parboiled white rice slightly more nutritious than regular white rice. The process also helps keep the rice grains separate when cooked. Instant rice has been fully cooked and then dehydrated after the milling process. It requires a much shorter time to cook compared to regular rice.
How to Cook Rice
Rice is commonly cooked by adding a certain amount of water and slowly heating it over low temperature until the grains absorb all the water. The rice is cooked over a heat source such as a fire, stovetop, or rice cooker. The node How to cook rice has many more comprehensive writeups concerning cooking rice so I won't go into more detail here.
Common Types of Rice
- Jasmine rice - This is an aromatic rice that is grown in Thailand. When cooked it is moist and has a delicate floral flavor and aroma. Jasmine rice is predominantly used in Asian dishes and can be found in both white and brown forms. It can serve as a substitute for basmati rice, however the flavor and aroma will be slightly different.
- Basmati rice - This rice is another aromatic rice and has been grown in India for thousands of years. Basmati has a nutty aroma and flavor that develops because it is often matured up to a year after harvesting. It is a long grain rice that stays fluffy and separate when cooked. It is mainly used in various Middle Eastern and Indian dishes such as curries and can be found in white and brown forms. Hybrid forms of basmati rice can also be purchased. Texmati is a type of basmati rice hybrid grown in Texas. It is fluffier and has a milder flavor than imported basmati. Pecan rice is another type of basmati grown in Louisiana. It has a nutty flavor and supposedly smells like popcorn.
- Black or red rice - These kinds of rice have a black or red bran instead of brown while the center of the rice is still white. The black form of rice is mainly grown in Southeast Asia while the red form is grown both in India and in the Carmargue region in France (thanks to BlueDragon for the info). Thai black rice actually chances color to a deep purple when it is cooked, making it an interesting visual choice for dishes such as rice pudding.
- Arborio rice - This is a short grain rice grown in Italy. The rice has a high amount of starch, which gives it a creamy consistency when cooked. The rice is also able to absorb a large amount of water without getting mushy. For these reasons arborio is the main type of rice used in risotto. When cooking this rice it is important not to rinse it before cooking. Rinsing will remove some of the starch, making the finished risotto less creamy. Arborio rice can be found in both white and brown forms.
- Glutinous rice - Also called sticky, sweet, pearl, or sushi rice. The names of the rice are misleading as it actually does not contain gluten and is not sweet. It is a very short grain rice that is chalky white in the center and is commonly used in sushi and Asian desserts. The rice is very sticky when cooked.
- Valencia rice - This medium grain rice also known as Spanish rice or paella rice is from Spain. It is mainly used in the traditional Spanish dish paella.
- Wild rice - The name is deceiving, as wild rice is not really rice but a seed of the water grass plant Zizania aquatica that is native to North America. It is cooked and used in the same way as rice. Check out anthropod's node for a detailed description of wild rice.
http://www.mycustompak.com/healthNotes/Food_Guide/Rice.htm
http://web.foodnetwork.com/food/web/encyclopedia/termdetail/0,7770,2760,00.html
http://www.wholehealthmd.com/refshelf/foods_view/1,1523,75,00.html
http://www.cgiar.org/research/res_rice.html
http://usda-ars-beaumont.tamu.edu/tidbit1.html
http://www.hort.purdue.edu/newcrop/Crops/Rice.html