Rice fortification – what are the methods to fortify?

Rice fortification has been an under-utilized opportunity. Technologies that have been used cost-effectively for nearly a century in wheat and maize milling could not be adapted to rice milling. Rice fortification is complex.

Here we highlight the main technologies available to fortify rice:

Hot extrusion passes dough made of rice flour, vitamin/mineral mix, and water through a single or twin screw extruder and cuts it into grain-like structures that resemble rice grains. This process involves relatively high temperatures (70-110°C) obtained by preconditioning and/or heat transfer through steam heated barrel jackets. It results in fully or partially pre-cooked simulated rice-like grains that have similar appearance (sheen and transparency) as regular rice kernels. The rice-premix thus developed is blended with natural polished rice at about 1:200 ratio to produce fortified rice.

Cold extrusion, also produces rice-shaped simulated grains by passing a dough made of rice flour, vitamin/mineral mix, and water through a simple pasta press. This technology does not utilize any additional thermal energy input other than the heat generated during the process itself, thus is primarily a low temperature (below 70°C), forming process resulting in grains that are uncooked, opaque, and easier to differentiate from regular rice kernels. The rice-premix thus developed is blended with natural polished rice at about 1:200 ratio to produce fortified rice.

Coating combines the vitamin/mineral mix with ingredients such as waxes and gums. The mixture is sprayed to the rice on the surface of grains in several layers to form the rice-premix and then is blended with polished rice. Manufacturers in Costa Rica, the Philippines and the United States use this process. The rice-premix thus developed is blended with natural polished rice at about 1:200 ratio to produce fortified rice.

Dusting, observed only in the U.S., involves dusting the polished rice grains with the powder form of the vitamin/mineral premix. The vitamin/mineral mix sticks to the grain surface because of electrostatic forces. Nutrients are removed through washing and therefore a remark on packages is required by law: ‘Do not rinse before or drain after cooking’.

Read the latest rice fortification toolkit from GAIN and Path here

Want to know more about rice fortification? Please review this document with the most common frequently asked questions.

Read a report: Introducting Fortified Rice in Cambodia and Vietnam

Want to understand more about rice fortification? View rice fortification in pictures on the GAIN Guardian platform here.