III.  The Composition of Rice and Various Processed Types

Paddy Rice or Rough Rice
Brown Rice
Milled Rice
Broken Rice
Rice Bran and Stabilized Rice Bran
Organic Rice
Parboiled Rice
Instant Rice
IQF Frozen Rice

Paddy Rice or Rough Rice.  In most of the world and in California, the term paddy rice is used to describe the rice as it comes from the field after harvest. The rice has been threshed and each grain is separate. The grain of rice has a hard husk protecting the kernel inside. The husk (or hull) that covers rice is much thicker and tougher than most cereal grain husks. Paddy rice is also called rough rice. (Primarily in the southern growing area of the U.S.) By weight, the composition of paddy rice is approximately: 22% husk (including about 2% trash), 10% bran, and 68% rice (2% of the rice are very small pieces, brewers rice, and fines). The rice portion can have varying percentages of broken kernels. A typical milling yield in California for medium grain would be described as 54/68. 54% head rice and 68% total. (14% brokens) In the southern growing area, a typical yield for long grain would be 58/68. In Japan where harvest and drying conditions are ideal a typical yield would be 67/70. Paddy rice is not as dense as milled rice and usually weighs about 37 lbs per cubic ft. Brown rice, milled rice, and brokens weigh about 52 lbs per cubic ft.

Most paddy rice is milled in the U.S. Some is exported to countries like Brazil, Mexico, and Turkey for milling. The export of paddy harms the milling industry and eventually the farmer. The U.S. is about the only country in the world that allows the export of paddy rice. It does not make sense from an economic standpoint (the unnecessary freight cost of hulls and bran). It only occurs when the importing country has some sort of duty advantage for paddy rice that allows it to occur.

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Brown Rice.  After the husk is removed the remaining product is called brown rice. Brown rice is more nutritious than white rice, but very little rice is consumed in the brown form. Brown rice contains a bran layer that is about 12% of the brown kernel by weight. The protein in white rice is much more nutritious than most cereal grains but has a low level of the essential amino acid, lysine. The protein level in bran layer of brown rice is higher and has more lysine. The protein in brown rice has one of the most complete essential amino acid profiles of any vegetable crop. (No vegetables alone are complete.) The rice bran layer of brown rice also contains digestible fiber as well as minerals and vitamins not found in milled rice. It was learned that incidences of beriberi were dramatically reduced when diets where switched from white milled rice to brown rice or even parboiled rice which contained more thiamin. The oil content of the rice bran contains several vitamin E components and valuable nutrients. Because minerals and vitamins are lost when the bran is removed, years ago many states passed laws requiring white rice to be fortified with vitamins and minerals. Despite its nutritional value, consumption of brown rice is low because it takes almost one hour to cook and many people do not care for the taste and texture. Unfortunately, once the husk is removed from rice, the bran layer starts going rancid and this contributes to the bitter taste of brown rice.

Very little brown rice is actually consumed in the U.S. or the world for that matter. Some rice is exported in the brown form (primarily to Japan and Europe) for further processing.

Milled Rice.  Milled Rice has had the hulls and bran removed. It is also called white rice or polished rice. Most milled rice sold into the domestic market has been milled very hard and has had the broken content removed to below 4%. Less expensive rice sold to export markets may be milled to a lessor degree and may have higher percentages of broken kernels. State laws require that milled rice sold to U.S. consumers be enriched with vitamins to make its nutritional value similar to brown rice. For this reason, cooking directions mention that the rice should not be washed. (The enrichment is usually a powder and is easily removed with water.) Most ethnic consumers who eat a lot of rice wash the rice to improve taste and texture. Much of the Japonica rice packaged in California is not enriched and is labeled as coated with glucose (allowed by law) for these consumers who do not like the taste of enrichment and who were going to wash it away anyway.

Almost all rice is consumed in the milled form, and most rice exported from the U.S. is exported in the milled form.

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Broken Rice. The kernel of rice can become cracked in the field, during the drying process, or during the milling process. Cracks are usually caused by moisture migrating too quickly within the kernel (drying too fast, or moisture being added back to a dry kernel). Often these cracks cause the kernels to break during milling and so broken rice is generated. The percentage of broken kernels (relative to total milled rice) generated during milling usually ranges from 12% to 24% in the U.S. Most brokens are removed during the milling process to less than 4% in order to give the consumer a high quality rice. Broken rice tends to get mushy during cooking and makes a poor quality table rice. There are different sizes of broken kernels. With long grain rice in the south brokens are often separated into different sizes. From largest to small they are called; second heads, screenings, and brewers. In California, where the kernel is smaller to begin with, the brokens kernels are only separated into second heads and brewers.

In the past most broken rice in the U.S. went to the beer industry. Today, most of the rice going into beer is now whole kernel. The dog food industry uses the majority of the broken rice. They tend to start with the lower quality brewers rice and then move into the more expensive screenings and second heads as needed. The rice flour industry is growing and tends to use the higher quality sorted second heads and screenings. The beer industry still takes some of the higher quality second heads. Some brokens are now being exported to Japan out of California.

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