Cooking with rice

Ever wonder how rice become so fluffy after cooking it? It is due to the process involved during rice cooking which is gelatinization. Before going into the details, here’s a brief introduction of starches. Starch consist of two glucose polymer: Amylose and Amylopectin. Amylopectin is a highly branched molecule that makes rice sticky during cooking. Amylose is a long, straight starch molecule that does not gelatinize during cooking.

During cooking, the heat energy causes the bonds between amylose and amylopectin to break and the branches within amylopectin to break. This process makes it easier for water to enter the starch granules. As more water enter, the starch granules expands and it break. As it breaks, the amylose molecules will migrate out of the starch granules into the surrounding water while the amylopectin remains in the starch. At this stage, the starch granules have been gelatinized. The leaching of amylose into the surrounding causes the amylose content to decrease which will increase the glycemic index (GI) of the rice as they are inversely proportion to each other.

It is common to use 1 cup of water to cook 1 cup of white rice, but what about brown rice or unpolished rice? Because of its unrefined outer layer, cooking unpolished rice requires more water to cook than polish rice. How much is too much water? Three different amounts of water are used to cook 1 cup of unpolished rice and red basmati each.

Comparison

Depending on the type of rice texture that you like, the amount of water use is different. The more water used, the rice will be more compact and porridge-like. I would say the right amount of water to produce a chewier texture would be about the same amount used in polished rice – 1:1. However, some elderly may prefer porridge-like texture as it is easier for them to eat. People who are not feeling well or have difficulties swallowing due to several reasons (eg: Dysphagia, sore throat) may want to consider this porridge-like texture for ease of consumption after consultation with a speech therapist.

To make rice palatable and interesting:

  1. Pre-soaking of rice– Soaking of rice before cooking would speed up the cooking duration. During pre-soaking, hydration occurs where water is absorbed. However, this process decreases the amylose content in the granules and thus causing an increase in GI. Therefore, for diabetic patients, it is not recommended to pre-soak rice before cooking.
  2. Use different cooking methods– Try cooking rice by using microwave or steam. The use of different cooking methods may produce different type of texture. The GI of the rice may vary as well – Microwave method may produce a lower GI as compared to regular rice cooker and steaming. However, microwaving may produce a harder and chewier texture as compared to regular rice cooking.
  3. Use a mixture of rice– For those who just started eating brown rice, start off with a mixture of refined rice and unrefined rice and gradually increase the amount of unrefined rice.
  4. Incorporate other types of wholegrains into the dish– Incorporating other grains like barley or legumes, may add texture to the rice.