Where and How Rice is Grown
Table of Contents
As a staple food for more than half of the world’s population – with Asia, Sub-Saharan Africa, and South America being the largest consuming regions – and with an annual global rice yield of approximately 535 million tons, rice is by far one of the most important commercial food crops.
In the rice industry, fifty countries produce rice, with China and India supporting 50% of total global rice production and Southeast Asian countries separately supporting an annual production rate of 9-23 million metric tons, of which they export very little, with over 300 million acres of Asian land used for growing rice.
Not only is rice eaten steamed or boiled – with rice cookers making the cooking process much simpler and near-effortless today – but rice grains can also be dried and ground into rice flour and used to make beer and liquors.
By-products from the growing and processing of rice create many valuable new rice products. Rice husks, rice stubble, rice bran, broken rice, and rice straw are used as common ingredients in different food products, livestock feed, and even industrial, household, and building products.
With rice production and the global rice trade being so lucrative and beneficial to so many around the world, you may be wondering about where rice growers are and how rice farming and rice cultivation work throughout the year. Here is how rice farms grow rice globally.
Where is Rice Grown and How is It Grown?
The earliest rice site may have been in China roughly 10,000 years ago. Some archaeological evidence suggests that China had rice fields as early as 2300 BCE and that places in South East Asia had rice farms at this time as well.
Rice most likely came to Western countries through the traders and voyagers of the Columbian Exchange in the fifteenth and sixteenth centuries. Meanwhile, Africa developed and domesticated its own species of rice called African rice (or Oryza glaberrima), though this variety didn’t gain as much popularity globally.
Rice plants produce a variety of short-grain rice, medium-grain rice, to long-grain rice, as well as aromatic rice like jasmine rice, basmati rice, and glutinous rice or sticky rice. There are three different types of rice: japonica, javanica, and indica.
Japonica rice varieties are high yielding and tend to be resistant to disease. Javanica types of rice fall between japonica and indica varieties in terms of yield, use, and hardiness. Although quite hardy, indica yields less than japonica types and are most often grown in the tropics like Southeast Asia.
Varieties of rice are selected and grown specifically for their end use. For U.S. rice, long-grain rice is typically used for boiling, quick-cook products, and soup, whereas shorter-grain rice is used in breakfast cereals, baby food, and liquors.
Because rice consumption and cultivation are so widespread, there are now four distinct types of rice farms or ecosystems. They are commonly referred to as irrigated, rainfed lowland, upland, and flood-prone agroecological zones. Irrigated rice ecosystems are the primary type found in East Asia providing 75% of most rice produced globally.
Rainfed lowland ecosystems only sustain one crop per growing season and flooded fields reach as much as 19.7 inches during part of the growing season. Rainfed low-land rice is grown in areas of South Asia and Southeast Asia and accounts for 25% of global rice production.
Upland zones are found in Asia, Africa, and Latin America and are the primary type in the rice industry of Latin America and West Africa. Upland rice fields are generally dry and directly seeded. Usually, rice seeds and rice crops are either sown simultaneously with another crop, intermittently with another crop, or the crop is shifted every few years to a new location.
Lastly, flood-prone ecosystems are prevalent in South and Southeast Asia and are characterized by periods of extreme flooding and drought, with yields being low and variable. Flooding occurs during the wet season from June to November, and rice varieties are chosen for their level of tolerance to submersion.
The Rice Production Process
Planting
Farmers begin rice production by soaking the rice seeds prior to planting. Then, depending on the level of mechanization and the size of the planting, seeding occurs in three ways in the rice industry. In many Asian countries that haven’t mechanized their rice farming practices, seeds are sown by hand. After 30-50 days of growth, the seedlings are transplanted in bunches from nursery beds to flooded paddies.
Seeds can also be sown using a machine called a drill that places the seed in the ground. Larger enterprises like the U.S. rice industry sow rice seed by airplane, with low-flying planes distributing rice seed onto already flooded fields.
Harvesting
Once the rice plants have reached full growth, approximately three months after planting, and the grain begins to ripen, the water is drained from the fields. As the fields dry, the grains ripen further and harvesting is commenced.
Depending on the size of the operation and the amount of mechanization, the rice crop is either harvested by hand or machine. By hand, rice plants are cut with sharp knives or
sickles. This practice still occurs for most Asian rice.
The rice plant can also be harvested by a mechanized hand harvester or by a tractor/horse-drawn machine that cuts and stacks the rice stalks. For U.S. rice growers, most operations use large combines to harvest and thresh the stalks. If the rice has been harvested by hand or by a semi-automated process, threshing is completed by flailing the stalks by hand or by using a mechanized thresher.
Once harvested, the rice is commonly named paddy rice. This is the name given to unmilled rice with its protective husk in place.
Drying
Before milling, rice grains must be dried in order to decrease the moisture content. This is done with artificially heated air or, more often, with the help of naturally occurring sunshine. Rice grains are left on racks in fields to dry out naturally. Once dried, the rice grain, now called rough rice, is ready for processing.
Hulling
Hulling can be done by hand by rolling or grinding the rough rice between stones. However, it is more often processed at a mill with the help of automated processes. The rough rice is first cleaned by passing through a number of sieves that sift out the debris, and blown air removes the top matter.
Once clean, the rice is hulled by a machine that mimics the action of the handheld stones. The shelling machine loosens the hulls from the rice by rolling them between two sheets of metal coated with abrasives. 80-90% of the kernel hulls are removed during this process.
From the shelling machine, the grains and hulls are conveyed to a stone reel that aspirates the waste hulls and moves the kernels to a machine that separates the hulled from the unhulled grains. By shaking the kernels, the paddy machine forces the heavier unhulled grains to one side of the machine, while the lighter-weight rice falls to the other end. The unhulled grains are then siphoned to another batch of shelling machines to complete the hulling process. Hulled rice grains are also known as brown rice.
Milling
Since it retains the outer bran layer of the rice grain, brown rice needs no other processing. However, along with added vitamins and minerals, the bran layers also contain oil that makes brown rice take a longer time to cook than white rice that goes through the milling process. That is one of the reasons why brown rice goes through rice mills further to create a more visually appealing white rice.
The brown rice runs through two huller machines that remove the outer bran layers from the grain. With the grains pressed against the inner wall of the huller and a spinning core, the layers are rubbed off. The core and inner wall move closer for the second hulling, ensuring the removal of all bran layers.
The now light-colored grain is cooled and polished by a brush machine. The smooth white rice is conveyed to a brewer’s reel, where over a wire mesh screen broken kernels are sifted out. Oftentimes, the polished rice is then coated with glucose to increase luster.
Enriching
Producing white rice in rice mills also removes much of the vitamins and minerals found primarily in the outer bran layers. Further processing is often done in order to restore the nutrients to the grain. Once complete, the rice is called converted rice.
White rice is converted in one of two ways. Prior to milling, the rice is steeped under pressure in order to transfer all the vitamins and minerals from the bran layers to the kernel itself. Once done, the rice is steamed, dried, and then milled.
Rice that has already been milled can be submersed in a vitamin and mineral bath that coats the grains. Once soaked, they are dried and mixed with unconverted rice.
Final Note
Growing rice has been such an essential part of life for many cultures globally and in the modern age, high-quality rice imports have become possible thanks to so many different countries that share their yields. From short- to long-grain rice and everything in between, this staple food has become an incredibly accessible part of our every day thanks to those that grow the rice we eat.
