You can use it, but it has to be mashed. It will boost the gravity w/o adding flavor or color. Not much different than just adding sugar really, except for being a little less fermentable depending on mash temp. Also, you do have to cook it in order to get the starches to become available. Kind of a pain for what it gives you. If you really needed rice for a recipe then the flaked or instant would work better since the starches are pre-gelatinized.