Rice Varieties Characteristics

There are over two thousand varieties of rice grown world-wide.

We will discuss limited varieties used in United States and India/Pakistan regions. The rice is characterized by the size of grain, the color of the bran (skin of the grain), type of starch and aroma.

Size of grain

1. Long grain rice: The grain is about 3 to 5 times longer than it's width. (6mm length)
2. Medium grain rice: The grain is about 2 to 3 times longer than width.(5 mm length)
3. Short grain rice: The grain is just slightly longer than its width. (4 mm long, 2.5 mm wide)

Color of grain

1. Brown Rice: The husk is removed keeping the bran layer and the endosperm.
2. White rice: The rice is polished removing the bran layer resulting in a loss of many minerals and fiber.
3. Red Rice: This has a red bran covering the endosperm instead of brown bran layer for brown rice. The endosperm is translucent with red to pink color.
4. Black Rice: This has a black bran covering the endosperm. The endosperm is translucent with gray to almost black.

Starch

There are two types of starch: Amylose, and Amylopectin. Longer grain rice has 22 percent Amylose and 78 Amylopectin while medium/short grain rice has 18 percent Amylose and 82 percent Amylopectin. Relatively higher the Amylopectin, stickier is the texture. Note corn starch is 100% Amylose. By cooking, this starch structure becomes gelatinized so that human body can digest it. The body converts the gelatinized starch into simple sugar.

Rice oil

Rice bran is about 20 % oil. This causes grain to turn rancid.

Rice Protein

The protein in Rice grain ranges between 5 and 10 percent. In general, lower the protein, better is the taste and texture.

Rice Aging

Rice gets harder with age as if the percentage of Amylose is increasing, but in reality it is not. The rice gets firmer and less sticky. Most of the rice loses its sticky-ness and aroma with age. The exception is Basmati. Basmati rice gets better with age.

Rough Rice

The rice grains are still in the hull. It is also called Paddy.

Brown Rice

The hull is removed. The brown color is caused because of the bran layer on the endosperm.

White Rice

The hull and the bran have been removed. This is also known as milled rice.

Parboiled Rice

This method was originally used in South India to enhance the nutritional value of the grain. It involves four steps: soaking, cooking, drying and then milling. The rough rice is soaked in plain water till its saturated for a few hours. Excess water is drained off and then paddy is cooked at 212º F for time enough to change starch structure to be gelatinized. Now the paddy is sun-dried. Dried paddy then milled. The husk is removed and then the grain may be polished. The parboiled rice gives a fluffy separate gain on cooking.
The actual process varies from variety to variety as well as the millers.

Polishing Rice

After the husk has been removed, Rice is fed in to a drum which is rotated at a very high speed under pressure. The rice grains rub against each other causing the heat from friction to reach over 350º F. Water vapor is introduced to moisten the grain surfaces causing the surface starch to gelatinize. The rice is dried. This process results in loss of bran surface, giving it a shiny appearance.
The actual process varies from variety to variety as well as the millers. Some millers also enrich their product with vitamins and minerals. Unfortunately, many users soak and wash rice before cooking getting rid of the most of the enrichment made to the grain by the miller.

Rice Types and Uses In Cooking

- Short-Grain (brown): Pudding, Desserts, Risotto 
- Short-Grain (white): Pudding, Desserts, Japanese sushi, Idli, Risotto 
- Sticky Rice: Sushi, Sweets, Deserts, Iraqi Pilaf 
- Medium-Grain (brown): Soups 
- Medium Grain (white): Risotto, Idli
- Long-Grain (brown): Pulao, Paella 
- Long-Grain (white): Kheer, Biryani, Pilaf, Pulao, Paella, Plain saffron

Special Rice Varieties

Basmati Rice: Long grain rice from India/Pakistan (USA has tried to produce a variety called "Texamati" with limited success.). Available White as well as Brown.
The Basmati grain contain 0.09 ppm of a the chemical compound (2-acetyl-1-pyrroline), which is about 12 times more concentration than un-scented rice varieties. This gives its fragrance. 
In Hindi, Bas (aroma), Mati (mother), literally means "mother of all aroma".

- Himalayan Red Rice : Long grain, aromatic. This variety is produced in India as well as France.
- Jasmine Rice: Long grain, aromatic, Thailand
- Arborio Rice: Italian White Medium grain Rice. In reality it is a large grain. Typically used to make Risotto. You can also make Idli with it.
- Carnaroli Rice: Italian White Short grain Rice.
- Botan Rice (Sushi Rice): Short Grain, Sticky, Available White as well as Brown. 
- Chinese Black Rice: Short grain Rice, High gluten
- Mochi Rice : Short grain, Glutinous White Rice. Japan
- Sweet or Waxy : Glutinous rice grown in the United States. This is short and chalky white rice primarily used to make frozen desserts and binders.
- Wehani Rice: Long grain, unpolished brown rice, aromatic. Cooks up fluffy and separate. 
- Wild Rice: Technically, it is NOT rice. This a grass seed grown in United States.