jopupi.blogg.se

This also makes the rice more resistant to weevils and lessens cooking time. The whole grain is vacuum-dried, then steamed, followed by another vacuum drying and husking. In the 1910s German-British scientist Erich Gustav Huzenlaub (1888–1964) and the British scientist and chemist Francis Heron Rogers invented a form of parboiling which held more of the nutrients in rice, now known as the Huzenlaub Process. The rice was then dried on woven mats, cooled and milled. In older methods, clean paddy rice was soaked in cold water for 36–38 hours to give it a moisture content of 30–35%, after which the rice was put in parboiling equipment with fresh cold water and boiled until it began to split. Minerals such as zinc or iron are added, increasing their potential bio-availability in the diet. In North America parboiled rice is often partially or fully precooked before sale. Parboiled rice takes less time to cook and is firmer and less sticky. However, this also makes the kernels harder and glassier. This increases the formation of type-3, resistant starch which can act as a prebiotic and benefit health in humans. Cooling brings retrogradation whereby amylose molecules re-associate with each other and form a tightly packed structure. The parboiled rice kernels should be translucent when wholly gelatinized. Through gelatinization, amylose molecules leach out of the starch granule network and diffuse into the surrounding aqueous medium outside the granules which, when fully hydrated are at maximum viscosity. The starches in parboiled rice become gelatinized, then retrograded after cooling. Parboiling drives nutrients, especially thiamin, from the bran to the endosperm, hence parboiled white rice is mostly nutritionally similar to brown rice. The treatment is practiced in many parts of the world. These steps make the rice easier to process by hand, while also boosting its nutritional profile, changing its texture, and making it more resistant to weevils. The three basic steps of parboiling are soaking, steaming and drying.

Parboiled rice (also called converted rice and easy-cook rice ) is rice that has been partially boiled in the husk. Partially cooked rice Parboiled rice Woman preparing parboiled rice in Nigeria Prepared parboiled rice