What is the process of converting the starch in whole corn or whole rice to useable sugar suitable for yeast consumption?
I've experimented with cooking then mashing but there isn't any or little sugar extraction. Do you need to precook or can you use the grain directly into your mash.
Unless your using some enzymatic malt in the mash you won't get sugar. So if you are trying to convert without the use of enzymatic malt you have to go a different direction. You can buy amylase which is usually derived from fungus or you can get some koji which is rice that is colonized by a particular type of fungus that will convert starch to sugar. This is how saki is made.
There are also enzymes in your saliva so you could chew a portion of your grain and spit it into your mash.
Both these last two methods are quite slow. The saki process adds the yeast at the same time so as the fungus conveys the starch the yeast ferment it.