Should rice be rinsed before cooking? Scientists clear up the confusion

Rinsing rice helps remove microplastics (by as much as 20-40%) and arsenic, but it also washes away some valuable nutrients. This is according to research conducted at Adelaide University in Australia. Scientists recommend not giving up rinsing rice altogether, but limiting it.

Effects of rinsing rice: less arsenic and microplastics, but also less copper, iron, zinc, and vanadium

Rinsing rice is often discussed in the context of removing arsenic, a harmful heavy metal that plants absorb from the soil. Running water does indeed wash some of this element from the surface of the grains. However, the U.S. Food and Drug Administration (FDA) recommends a different and more effective way to reduce arsenic levels. This involves cooking rice in a large amount of water and then draining it thoroughly. During this process, some of the arsenic transfers into the cooking water, and the FDA estimates that as much as 40-60% can be removed.

Rinsing rice before cooking does more than remove arsenic. Scientists from Adelaide University in Australia indicate that it can also eliminate as much as 20-40% of microplastics. However, they also point out the drawbacks of the process. Rice loses some valuable nutrients, including copper, zinc, iron, and vanadium. Although rice is not a particularly rich source of these minerals, it is still worth trying to preserve them.

Does rinsing rice affect how sticky it becomes?

Rinsing rice removes starch known as amylose from the surface of the grains. This changes their texture. For a long time, it was believed that rinsed rice could not become sticky, such as the sticky rice commonly used in Asian cuisine. Evangeline Mantzioris of Adelaide University in Australia conducted a study showing that stickiness is actually influenced by a different type of starch, amylopectin. This starch is located inside the grains and is therefore not removed during rinsing.

Achieving a sticky texture is possible by choosing the appropriate type of rice. Scientists from Adelaide University in Australia tested this using ten-gram samples of three rice varieties. Each sample was thoroughly rinsed and then cooked. The results showed that Asian short-grain glutinous rice was the stickiest. Medium-grain and jasmine rice were significantly less sticky.

Rinsing rice in the past and today

As Evangeline Mantzioris notes, many societies have traditionally rinsed rice to remove dust, small stones, insects, and husks. However, this is generally unnecessary when rice is purchased from stores. Commercial rice is thoroughly cleaned by machine, dried, and dehusked. Its processing and packaging are subject to strict standards. Drying reduces moisture levels and prevents the growth of microorganisms. Consumers can therefore expect store-bought rice to be safe and not require additional rinsing before cooking.

Should you stop rinsing rice?

The Australian researchers do not encourage consumers to stop rinsing rice completely. However, they recommend doing it in moderation. One of the researchers, Bo Wang, says: “n short, for most consumers, gently rinsing rice once or twice will be sufficient. This approach helps maintain a balance between the benefits and drawbacks. The grains are cleaned, while still retaining valuable nutrients.