Rice is often cooked by simple boiling, but a new cooking method developed by scientists reduces calories from the cereal grain by half. This process could help reduce obesity rates in Asia and other areas where the food is a staple part of a normal diet.
Obesity levels are rising around the world as serving sizes increase, and people, on average, lead increasingly sedentary lifestyles. Along with fatty foods in areas where traditional diets are largely plant-based, carbohydrates and starches are also being consumed in larger quantities.
Rice contains both digestible and indigestible starches, and digestible starches are broken down into sugars in the small intestines, before these molecules pass into the bloodstream.
Some of the sugars left over from this process are stored in the liver and muscles in the form of glycogen, a type of carbohydrate. This polysaccharide can then be converted by the body back into chemical fuel when needed. However, leftover sugars are stored as fat, which can lead to obesity.
Rice prepared by traditional methods contains around 240 calories per cup. Increasing the concentration of nondigestible starches could be one way of reducing the number of calories taken in by the body from rice, researchers theorized.
"Because obesity is a growing health problem, especially in many developing countries, we wanted to find food-based solutions. We discovered that increasing rice resistant starch (RS) concentrations was a novel way to approach the problem," Sudhair James of the College of Chemical Sciences, Colombo, Western, Sri Lanka said.
The new cooking method consists of adding a teaspoon of coconut oil to boiling water before adding half a cup of uncooked rice. This is then simmered for 40 minutes, although boiling for 20 to 25 minutes would also be suitable for the method. After cooking, the rice is refrigerated for 12 hours.
This cooking method results in coconut oil absorbing into the rice, altering starch molecules so that digestive enzymes have a reduced effect on the chain-like molecules. Cooling forms hydrogen bonds between molecules of amylose, the digestible component of starch, increasing the resistance of the molecules to the actions of enzymes. Reheating did not add calories back to the rice, researchers determined.
Further research will examine whether oils other than coconut will have the same effect. Human trials could also reveal the effect of the new cooking method on real-world weight loss.
Rice has been cultivated by humans for between 8,200 and 13,500 years, and the food currently supplies 20 percent of all the calories consumed worldwide.
Development of the new method of cooking rice was announced at the 249th National Meeting & Exposition of the American Chemical Society (ACS), held in Denver, Colo., from March 22 to 26.
Photo: Alexis Breaux | Flickr
