Putting aside the obvious question, Why?, rice has to go through a starch conversion process and the resulting sugars in solution are boiled down into a syrup. If you are all-grain brewing you can simply add ground rice via a cereal mash to your grist and make beer. Making rice syrup without having all-grain capabilities would require cooking the rice then subjecting it to a commercial enzyme product and then somehow drawing off the converted sugars and cooking down the liquid into the previously mentioned syrup. So again, why not just use rice (flaked rice is even easier) or just buy rice syrup or the rice syrup solids?
Long story short. Rice syrup expensive and trendy,(low glycemic index) No recipes online. Wondering if an opportunity here to justify fiddleyness.
Yes enzymes come from addition of malt. No idea how much.
So no this not for brewing.
