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.
The gelatinization temperatures for corn and rice are higher than mash temperatures. Those grains need to be cooked so that the starch will go from hard granules to a form that can be converted to sugar. The enzymes from the malt in the mash will do the conversion, just as the enzymes convert the starch in barley or wheat malt to sugar. The corn and rice are milled before cooking.
I do CAPs using corn meal and a cereal mash to gelatinize. Then the cereal mash is added back to the main mash. One uses malts high in Diastatic Power so that there are plenty of enzymes - 6 row or NA 2 row will be good for this.
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.
I have NEVER made saliva beer. I will make saliva beer only when all other sources of amylase are unavailable and the apocalypse has made it impossible to get beer in ANY OTHER WAY. INCLUDING BMC.
And even if it gelatinizes at mash temp, it may take a while depending on size/type, right? For instance, whole brown rice needs 45 minutes to cook though. So those starches wouldn’t be available until the very end of a mash.