Rice Bran Oil Uses and Health Benefits


Pure rice bran oil, exhibits excellent frying performance and contributes a pleasant flavor to the fried food. It possesses good storage stability and fry life without hydrogenation. These properties make it a premium choice for frying upscale products with delicate flavors. Most Japanese restaurants in the USA have now switched to Rice Bran Oil for their Tempura Frying Oil because of its superior performance in this special application. General frying applications, ranging from French fries to chicken, rice bran oil exhibits excellent taste and texture. Since hydrogenation isn't required for stability, it is a natural high-quality liquid frying oil that is also free of trans-fatty acids.

Rice Bran Oil is also a great choice for use in stir-frying. While its delicate, nut-like character complements the natural flavor of stir-fried meats, seafoods and vegetables, it never overpowers them. A further advantage is its natural resistance to smoking at high frying temperatures. Not surprisingly, rice bran oil has quickly become the oil of choice by many high-end Asian-American restaurants.

Salad Dressing
Rice Bran Oil has a light, barely perceptible flavor, making it wonderful to use with gourmet vinegars and spices. The oil emulsifies easily, so dressings don't separate.


Because of rice oil's light flavor, it has found favor in baking applications. Brownies and other baked goods made with rice oil turn out light and delicious. Baking sheets and cake pans coated with rice oil allow the baked goods to come out of the pan or off the cookie sheet with no trouble at all.

Soap Manufacturing
Rice Bran Oil has a long and successful history in Japan as a base for soaps and skin creams. The oil is purported to reverse the effect of aging by slowing the formation of facial wrinkles thanks to rice bran oil's rich concentration of Vitamin E and gamma-oryzanol. In Japan, women who use rice bran oil on their skin are known as 'rice bran beauties'. In the US, rice oil has gained a strong and loyal following with soap manufacturers and artisans.

Supplement for Horses, Dogs and other animals
Rice oil has found favor with performance horses or older horses that have a difficult time keeping weight on. The rice oil is purported to give horse and dog coats a rich, shiny look. Some zoos are even feeding rice oil as a supplement to their tigers and lions!


Gamma Oryzanol
Rice bran oil is rich in gamma-oryzanol, a group of ferulate esters of triterpene alcohols and phytosterols. The high antioxidant property of gamma-oryzanol has been widely recognized. Studies have shown several physiological effects related to gamma-oryzanol and related rice bran oil components. These include its ability to reduce plasma cholesterol, reduce cholesterol absorption and decrease early atherosclerosis, inhibit platelet aggregation, and increase fecal bile acid excretion. Oryzanol has also been used to treat nerve imbalance and disorders of menopause.

Rice bran oil is the only readily available oil, other than palm, that contains significant levels (approximately 500 ppm) of tocotrienols. These occur in at least four known forms and are similar to the tocopherols in chemical structure. They belong to the vitamin E family and are powerful natural antioxidants. The protective benefits of dietary antioxidants in the prevention of cardiovascular disease and some forms of cancer have been widely publicized.

Rice Bran Oil is a healthy oil with uses in cooking, frying, as a salad dressing, baking, soap making, as even a supplement to horses, dogs and other animals.

Why Rice Bran Oil in cooking? For grilling, you need an oil that can take the heat. Specifically, you want an oil with a high smoke point, the point at which oil starts to smoke. When cooking, you don't want your oil to smoke, because it imparts a negative flavor to the foods.

Rice bran oil's smoke point is 490 degrees F, higher than even grapeseed oil (480 degrees) or peanut oil (320 - 450 degrees). This means that even in the hottest of situations, rice bran oil won't smoke or breakdown. Your foods will taste better, and they will be less likely to stick to the grill or griddle.

Pure rice bran oil is a rich source of Vitamin E, an anti-oxidant. Rice bran oil is also a rich in the neutraceutical gamma-oryzanol (see below for health benefits).

Rice Bran Oil has NO cholesteral and NO trans fatty acids. It is naturally low in saturated fat.

Rice Bran Oil is also rich in oleic and linoleic fatty acids.

Rice Bran Oil is naturally free of trans fatty acids (TFA's)

From :http://www.honestfoods.com/topgriloil.html

Rice bran and germ oil

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Rice bran oil

Rice bran oil is the oil extracted from the germ and inner husk of rice. It is notable for its very high smoke point of 490°F (254°C) and its mild flavor, making it suitable for high-temperature cooking methods such as stir frying and deep frying.[1] It is popular as a cooking oil in several Asian countries, including Japan and China.[2]

Rice bran oil contains a range of fats, with 47% of its fats monounsaturated, 33% polyunsaturated, and 20% saturated. The fatty acid composition of rice bran oil is:[3]

Fatty acid :

Palmitic 15.0%
Stearic 1.9%
Oleic 42.5%
Linoleic 39.1%
Linolenic 1.1%
Arachidic 0.5%
Behenic 0.2%

Rice bran oil is rich in vitamin E, γ-oryzanol (an antioxidant that may help prevent heart attacks[4]), and phytosterols (compounds believed to help lower cholesterol absorption[5][6]), which may provide associated health benefits.

Rice bran oil was traditionally used in Southern India for cooking. A decline in usage has occurred for the last three decades. This decline is gaining momentum due to the increasing number of restaurants.

From : http://en.wikipedia.org/wiki/Rice_bran_oil

Rice Global history

According to the Encyclopædia Britannica:[16]

The origin of rice culture has been traced to India in about 3000 BC. Rice culture gradually spread westward and was introduced to southern Europe in medieval times. With the exception of the type called upland rice, the plant is grown on submerged land in the coastal plains, tidal deltas, and river basins of tropical, semitropical, and temperate regions. The seeds are sown in prepared beds, and when the seedlings are 25 to 50 days old, they are transplanted to a field, or paddy, that has been enclosed by levees and submerged under 5 to 10 cm (2 to 4 inches) of water, remaining submerged during the growing season.

Wild Oryza rice appeared in the Belan and Ganges valley regions of northern India as early as 4530 BC and 5440 BC respectively. Agricultural activity during the second millennium BC included rice cultivation in the Kashmir and Harrappan regions.[17] Mixed farming was the basis of Indus valley economy. Farmers planted their crops in integrated fields. Rice, grown on the west coast, was cultivated in the Indus valley.[18] Rice, along with barley, meat, dairy products and fish constituted the dietary staple of the ancient Dravidian people.[19]

There is mention of ApUpa, Puro-das and Odana (rice-gruel) in the Rig Veda, terms that refer to rice dishes,[20] The rigvedic commentator Sayana refers to "tandula" when commenting on RV 1.16.2., which means rice.[21] The Rigvedic term dhana (dhanaa, dhanya) means rice.[22] Both Charaka and Sushruta mention rice in detail.[23] The Arthasastra discusses aspects of rice cultivation.[24] The Kashyapiyakrishisukti by Kashyapa is the most detailed ancient Sanskrit text on rice cultivation.[25]

Continental East Asia
Z. Zhao, a Chinese palaeoethnobotanist, hypothesizes that people of the Late Pleistocene began to collect wild Oryza rice. Zhao explains that the collection of wild rice from an early date eventually led to its domestication and then the exclusive use of domesticated rice strains by circa 6400 BC at the latest.[26] Stone tool evidence from the Yunchanyan site in Hunan province suggests the possibility that Early Neolithic groups cultivated rice as early as circa 9000 BC.[27] Crawford and Shen point out that calibrated radiocarbon dates show that direct evidence of the earliest cultivated rice is no older than 7000 BC. Jared Diamond, a biologist and popular science author, summarizes some of the research done by archaeologists and estimates that the earliest attested domestication of rice took place in China by 7500 BC.[28]

Rice farmer in northern CambodiaAn early archaeological site from which rice was excavated is Pengtoushan in the Hupei basin. This archaeological site was dated by AMS radiocarbon techniques to 6400–5800 BC (Zohary and Hopf 2000), but most of the Neolithic sites in China with finds of charred rice and radiocarbon dates are from 5000 BC or later.[29] This evidence leads most archaeologists to say that large-scale dry-land rice farming began between 5000 and 4500 BC in the area of Yangtze Delta (for example Hemudu culture, discovered in 1970s), and the wet-rice cultivation began at approximately 2500 BC in the same area (Liangzhu culture). It is now commonly thought that some areas such as the alluvial plains in Shaoxing and Ningbo in Zhejiang province are the cradle-lands of East Asian rice cultivation.[30] Finally, ancient textual evidence of the cultivation of rice in China dates to 3000 years ago.

Bruce Smith of the Smithsonian Institution advises caution on the Chinese rice hypothesis.[31] No morphological studies have been done to determine whether the grain was domesticated.[31] According to Smith such a rice would have larger seeds compared to the wild varieties, and would have a strong rachis or spine for holding grain.[31]

Korean peninsula and Japan

Utagawa Hiroshige, Rice field in Oki province, view of O-Yama.In 2003, Korean archaeologists discovered burnt grains (domesticated rice) in Soro-ri, Korea, that predate the oldest grains in China. This find challenges the mainstream explanation that domesticated rice originated in China.[32]

Mainstream archaeological evidence derived from palaeoethnobotanical investigations indicate that dry-land rice was introduced to Korea and Japan some time between 3500 and 1200 BC. The cultivation of rice in Korea and Japan during that time occurred on a small-scale, fields were impermanent plots, and evidence shows that in some cases domesticated and wild grains were planted together. The technological, subsistence, and social impact of rice and grain cultivation is not evident in archaeological data until after 1500 BC. For example, intensive wet-paddy rice agriculture was introduced into Korea shortly before or during the Middle Mumun Pottery Period (c. 850–550 BC) and reached Japan by the Final Jōmon or Initial Yayoi circa 300 BC.[33][34]

Southeast Asia

Using water buffalo to plough rice fields in Java; Indonesia is the world's third largest paddy rice producer and its cultivation has transformed much of the country's landscape.Rice is the staple for all classes in contemporary South East Asia, from Myanmar to Indonesia. In Indonesia, evidence of wild Oryza rice on the island of Sulawesi dates from 3000 BCE. The evidence for the earliest cultivation, however, comes from eighth century stone inscriptions from Java, which show kings levied taxes in rice. Divisions of labor between men, women, and animals that are still in place in Indonesian rice cultivation, can be seen carved into the ninth-century Prambanan temples in Central Java. In the sixteenth century, Europeans visiting the Indonesian islands saw rice as a new prestige food served to the aristocracy during ceremonies and feasts. Rice production in Indonesian history is linked to the development of iron tools and the domestication of water buffalo for cultivation of fields and manure for fertilizer. Once covered in dense forest, much of the Indonesian landscape has been gradually cleared for permanent fields and settlements as rice cultivation developed over the last fifteen hundred years.[35]

In the Philippines, the greatest evidence of rice cultivation since ancient times can be found in the Cordilera Mountain Range of Luzon in the provinces of Apayao, Benguet, Mountain Province and Ifugao. The Banaue Rice Terraces (Tagalog: Hagdan-hagdang Palayan ng Banaue)are 2,000 to 3,000-year old terraces that were carved into the mountains by ancestors of the Batad indigenous people. It is commonly thought that the terraces were built with minimal equipment, largely by hand. The terraces are located approximately 1,500 meters (5000 ft) above sea level and cover 10,360 square kilometers (about 4,000 square miles) of mountainside. They are fed by an ancient irrigation system from the rainforests above the terraces. It is said that if the steps are put end to end it would encircle half the globe. The Rice Terraces (UNESCO World Heritage Site) are commonly referred to by Filipinos as the "Eighth Wonder of the World".

Evidence of wet rice cultivation as early as 2200 BC has been discovered at both Ban Chiang and Ban Prasat in Thailand.

By the 19th Century, encroaching European expansionism in the area increased rice production in much of South East Asia, and Thailand, then known as Siam. British Burma (now Myanmar) became the world's largest exporter of rice, from the turn of the 20th century up till the 1970s, when neighbouring Thailand exceeded Myanmar.


Rice crop in MadagascarAfrican rice has been cultivated for 3500 years. Between 1500 and 800 BC, O. glaberrima propagated from its original centre, the Niger River delta, and extended to Senegal. However, it never developed far from its original region. Its cultivation even declined in favour of the Asian species, possibly brought to the African continent by Arabs coming from the east coast between the 7th and 11th centuries CE.

In parts of Africa under Islam, rice was chiefly grown in southern Morocco. During the tenth century rice was also brought to east Africa by Muslim traders. Although, the diffusion of rice in much sub-Saharan Africa remains uncertain, Muslims brought it to the region stretching from Lake Chad to the White Nile.[36]

The actual and hypothesized cultivation of rice (areas shown in green) in the Old World (both Muslim and non-Muslim regions) during Islamic times (700-1500). Cultivation of rice during pre-Islamic times have been shown in orange.[36]
[edit] Middle East
According to Zohary and Hopf (2000, p. 91), O. sativa was introduced to the Middle East in Hellenistic times, and was familiar to both Greek and Roman writers. They report that a large sample of rice grains was recovered from a grave at Susa in Iran (dated to the first century AD) at one end of the ancient world, while at the same time rice was grown in the Po valley in Italy. However, Pliny the Elder writes that rice (oryza) is grown only in "Egypt, Syria, Cilicia, Asia Minor and Greece" (N.H. 18.19).[citation needed]

After the rise of Islam, rice was grown anywhere there was enough water to irrigate it. Thus, desert oases, river valleys, and swamp lands were all important sources of rice during the Muslim Agricultural Revolution.[36]

In Iraq rice was grown in some areas of southern Iraq. With the rise of Islam it moved north to Nisibin, the southern shores of the Caspian Sea and then beyond the Muslim world into the valley of Volga. In Israel, rice came to be grown in the Jordan valley. Rice is also grown in Yemen.[36]

The Muslims (later known as Moors) brought Asiatic rice to the Iberian Peninsula in the tenth century. Records indicate it was grown in Valencia and Majorca. In the case of Majorca, the rice cultivation stopped after the Christian conquest, although historians aren't certain.[36]

Muslims also brought rice to Sicily, where it was an important crop.[36]

After the middle of the 15th century, rice spread throughout Italy and then France, later propagating to all the continents during the age of European exploration.

United States

South Carolina rice plantation (Mansfield Plantation, Georgetown.)In 1694, rice arrived in South Carolina, probably originating from Madagascar. The Spanish brought rice to South America at the beginning of the 17th century.

In the United States, colonial South Carolina and Georgia grew and amassed great wealth from the slave labor obtained from the Senegambia area of West Africa and from coastal Sierra Leone. At the port of Charleston, through which 40% of all American slave imports passed, slaves from this region of Africa brought the highest prices, in recognition of their prior knowledge of rice culture, which was put to use on the many rice plantations around Georgetown, Charleston, and Savannah. From the slaves, plantation owners learned how to dyke the marshes and periodically flood the fields. At first the rice was milled by hand with wooden paddles, then winnowed in sweetgrass baskets (the making of which was another skill brought by the slaves). The invention of the rice mill increased profitability of the crop, and the addition of water power for the mills in 1787 by millwright Jonathan Lucas was another step forward. Rice culture in the southeastern U.S. became less profitable with the loss of slave labor after the American Civil War, and it finally died out just after the turn of the 20th century. Today, people can visit the only remaining rice plantation in South Carolina that still has the original winnowing barn and rice mill from the mid-1800's at the historic Mansfield Plantation in Georgetown, SC. The predominant strain of rice in the Carolinas was from Africa and was known as "Carolina Gold." The cultivar has been preserved and there are current attempts to reintroduce it as a commercially grown crop.[37]

American long-grain riceIn the southern United States, rice has been grown in southern Arkansas, Louisana, and east Texas since the mid 1800s. Many Cajun farmers grew rice in wet marshes and low lying prairies. In recent years rice production has risen in North America, especially in the Mississippi River Delta areas in the states of Arkansas and Mississippi.

Rice cultivation began in California during the California Gold Rush, when an estimated 40,000 Chinese laborers immigrated to the state and grew small amounts of the grain for their own consumption. However, commercial production began only in 1912 in the town of Richvale in Butte County.[38] By 2006, California produced the second largest rice crop in the United States,[39] after Arkansas, with production concentrated in six counties north of Sacramento.[40] Unlike the Mississippi Delta region, California's production is dominated by short- and medium-grain japonica varieties, including cultivars developed for the local climate such as Calrose, which makes up as much as eighty five percent of the state's crop.[41]

References to wild rice in the Americas are to the unrelated Zizania palustris

More than 100 varieties of rice are commercially produced primarily in six states (Arkansas, Texas, Louisiana, Mississippi, Missouri, and California) in the U.S.[42] According to estimates for the 2006 crop year, rice production in the U.S. is valued at $1.88 billion, approximately half of which is expected to be exported. The U.S. provides about 12% of world rice trade.[43] The majority of domestic utilization of U.S. rice is direct food use (58%), while 16 percent is used in processed foods and beer respectively. The remaining 10 percent is found in pet food.[44]

Although attempts to grow rice in the well-watered north of Australia have been made for many years, they have consistently failed because of inherent iron and manganese toxicities in the soils and destruction by pests.

In the 1920s it was seen as a possible irrigation crop on soils within the Murray-Darling Basin that were too heavy for the cultivation of fruit and too infertile for wheat.[45]

Because irrigation water, despite the extremely low runoff of temperate Australia, was (and remains) very cheap, the growing of rice was taken up by agricultural groups over the following decades. Californian varieties of rice were found suitable for the climate in the Riverina, and the first mill opened at Leeton in 1951.

Even before this Australia's rice production greatly exceeded local needs,[46] and rice exports to Japan have become a major source of foreign currency. Above-average rainfall from the 1950s to the middle 1990s[47] encouraged the expansion of the Riverina rice industry, but its prodigious water use in a practically waterless region began to attract the attention of environmental scientists. These became severely concerned with declining flow in the Snowy River and the lower Murray River.

Although rice growing in Australia is exceedingly efficient and highly profitable due to the cheapness of land, several recent years of severe drought have led many to call for its elimination because of its effects on extremely fragile aquatic ecosystems. Politicians, however, have not made any plan to reduce rice growing in southern Australia.

From :http://en.wikipedia.org/wiki/Rice

Rice Production history

Genetic history

All or part of this article may be confusing or unclear.

Two species of rice were domesticated, Asian rice (O. sativa) and African rice (O. glaberrima). According to Londo and Chiang, O. sativa appears to have been domesticated from wild (Asian) Oryza rice, Oryza rufipogon around the foothills of the Himalayas, with O. sativa var. indica on the Indian side and O. sativa var. japonica on the Chinese and Japanese side.[13] The different histories have led to different ecological niches for the two main types of rice. Indica are mainly lowland rices, grown mostly submerged, throughout tropical Asia, while japonica are usually cultivated in dry fields, in temperate East Asia, upland areas of Southeast Asia and high elevations in South Asia. (Oka 1988)

Japanese short-grain riceCurrent genetic analysis suggests that O. sativa would be best divided into five groups, labeled indica, aus, aromatic, temperate japonica and tropical japonica. The same analysis suggests that indica and aus are closely related, as are tropical japonica, temperate japonica, and aromatic.[14] Further analysis of the genetic material of various types of rice indicates that japonica was the first cultivar to emerge, followed by the indica, aus, and aromatic groups, whose genome did show significant differences in age. Within the japonica group, there is some genetic evidence that temperate japonica is derived from tropical japonica.[15]

Other studies have suggested that there are three groups of Oryza sativa cultivars: the short-grained "japonica" or "sinica" varieties, exemplified by Japanese rice; the long-grained "indica" varieties, exemplified by Basmati rice; and the broad-grained "javonica" varieties, which thrive under tropical conditions (Zohary and Hopf, 2000). The earliest find site for the japonica variety, dated to the 5th millennium BCE, was in the earliest phases of the Hemudu culture on the south side of Hangzhou Bay in China, but was found along with japonica types.[citation needed]

From :http://en.wikipedia.org/wiki/Rice

Rice Cooking

There are many varieties of rice; for many purposes the main distinction is between long- and short-grain rice. The grains of long-grain rice tend to remain intact after cooking; short-grain rice becomes more sticky. Short-grain rice is used for sweet dishes, and for risotto and many Spanish dishes.

Rice is cooked by boiling or steaming, and absorbs water during cooking. It can be cooked in just as much water as it absorbs (the absorption method), or in a large quantity of water which is drained before serving (the rapid-boil method). Electric rice cookers, popular in Asia and Latin America, simplify the process of cooking rice. Rice is often heated in oil before boiling, or oil is added to the water; this is thought to make the cooked rice less sticky.

In Arab cuisine rice is an ingredient of many soups and dishes with fish, poultry and meat. It is also used to stuff vegetables or is wrapped in grape leaves. When combined with milk, sugar and honey, it is used to make desserts. In some regions, such as Tabaristan, bread is made using rice flour. Medieval Islamic texts spoke of medical uses for the plant.[11]

Also extremely popular are combination cooking methods; for example fried rice is boiled or steamed rice stir-fried in oil.

Rice may also be made into rice porridge (also called congee or rice gruel) by adding more water than usual, so that the cooked rice is saturated with water to the point that it becomes very soft, expanded, and fluffy. Rice porridge is commonly eaten as a breakfast food, and is also a traditional food for the sick.

Rice may be soaked prior to cooking, which decreases cooking time. For some varieties, soaking improves the texture of the cooked rice by increasing expansion of the grains.

In some countries parboiled rice, also known as Minute rice or easy-cook rice, is popular. Parboiled rice is subjected to a steaming or parboiling process while still a brown rice. This causes nutrients from the outer husk to move into the grain itself. The parboil process causes a gelatinisation of the starch in the grains. The grains become less brittle, and the color of the milled grain changes from white to yellow. The rice is then dried, and can then be milled as usual or used as brown rice. Milled parboiled rice is nutritionally superior to standard milled rice. Parboiled rice has an additional benefit in that it does not stick to the pan during cooking as happens when cooking regular white rice.

A nutritionally superior method of preparing brown rice known as GABA Rice or GBR (Germinated Brown Rice)[12] may be used. This involves soaking washed brown rice for 20 hours in warm water (38°C or 100°F) prior to cooking it. This process stimulates germination, which activates various enzymes in the rice. By this method, a result of research carried out for the United Nations Year of Rice, it is possible to obtain a more complete amino acid profile, including GABA.

Cooked rice can contain Bacillus cereus spores which produce an emetic toxin when left at 4–60°C [8]. When storing cooked rice for use the next day, rapid cooling is advised to reduce the risk of contamination.

From : http://en.wikipedia.org/wiki/Rice

Rice Preparation as food

The seeds of the rice plant are first milled using a rice huller to remove the chaff (the outer husks of the grain). At this point in the process, the product is called brown rice. The milling may be continued, removing the 'bran' (i.e. the rest of the husk and the germ), thereby creating white rice. White rice, which keeps longer and is preferred by most, lacks some important nutrients; in a limited diet which does not supplement the rice, brown rice helps to prevent the deficiency disease beriberi.

White rice may be also buffed with glucose or talc powder (often called polished rice, though this term may also refer to white rice in general), parboiled, or processed into flour. White rice may also be enriched by adding nutrients, especially those lost during the milling process. While the cheapest method of enriching involves adding a powdered blend of nutrients that will easily wash off (in the United States, rice which has been so treated requires a label warning against rinsing), more sophisticated methods apply nutrients directly to the grain, coating the grain with a water insoluble substance which is resistant to washing.

Despite the hypothetical health risks of talc (such as stomach cancer),[9] talc-coated rice remains the norm in some countries due to its attractive shiny appearance, but it has been banned in some and is no longer widely used in others such as the United States. Even where talc is not used, glucose, starch, or other coatings may be used to improve the appearance of the grains; for this reason, many rice lovers still recommend washing all rice in order to create a better-tasting rice with a better consistency, despite the recommendation of suppliers. Much of the rice produced today is water polished.[citation needed]

Rice bran, called nuka in Japan, is a valuable commodity in Asia and is used for many daily needs. It is a moist, oily inner layer which is heated to produce an oil. It is also used as a pickling bed in making rice bran pickles and Takuan.

Raw rice may be ground into flour for many uses, including making many kinds of beverages such as amazake, horchata, rice milk, and sake. Rice flour does not contain gluten and is suitable for people on a gluten-free diet. Rice may also be made into various types of noodles. Raw wild or brown rice may also be consumed by raw-foodist or fruitarians if soaked and sprouted (usually 1 week to 30 days).

Processed rice seeds must be boiled or steamed before eating. Cooked rice may be further fried in oil or butter, or beaten in a tub to make mochi.

Rice is a good source of protein and a staple food in many parts of the world, but it is not a complete protein: it does not contain all of the essential amino acids in sufficient amounts for good health, and should be combined with other sources of protein, such as nuts, seeds, beans or meat.[10]

Rice, like other cereal grains, can be puffed (or popped). This process takes advantage of the grains' water content and typically involves heating grains in a special chamber. Further puffing is sometimes accomplished by processing pre-puffed pellets in a low-pressure chamber. The ideal gas law means that either lowering the local pressure or raising the water temperature results in an increase in volume prior to water evaporation, resulting in a puffy texture. Bulk raw rice density is about 0.9 g/cm³. It decreases more than tenfold when puffed.

From : http://en.wikipedia.org/wiki/Rice