[jimrod]

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.

[hopfenundmalz]

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.

Further reading.
http://morebeer.com/brewingtechniques/library/backissues/issue3.5/renner.html

[b-hoppy]

You have to cook the unmalted grains to gelatinize the starch prior to adding it to your mash.  http://byo.com/bock/item/442-cereal-mashing-techniques

edit: oops!  All good~

[morticaixavier]

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.

[klickitat jim]

Beano?

Mort, do you dry hop your saliva beer?

[morticaixavier]

Beano?

Mort, do you dry hop your saliva beer?

Just to be TOTALLY clear:

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.

Or I get really really bored one day 

[denny]

Looks to me like both corn and rice gelatinize at mash temps...

[Jimmy K]

Looks to me like both corn and rice gelatinize at mash temps...

Only short grain rice.
 
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.

[klickitat jim]

Flaked means gelatinized doesn't it? If so why not use flaked rice?

[majorvices]

One point: Corn has a better flavor to me than rice.

I like using flaked maize, even use it in my tripel. Works well and gives a good yield.

[Jimmy K]

Flaked means gelatinized doesn't it? If so why not use flaked rice?

Yes, flaked maize, rice, wheat, etc can be added directly to the mash.

[Joe Sr.]

One point: Corn has a better flavor to me than rice.

I agree.  Though it may be more that the rice addition doesn't add much flavor at all.

It's been years, but I did side by side batches with the only variation being rice or corn.  The corn batch tasted better hands down.

FWIW, I've never done the cereal mash route.  I've always used flaked maize or minute rice.

[majorvices]

I've done cereal mash with grits and I'm not sure if I could tell a difference. Flaked is so darn easy! Just toss in the mash!

[ynotbrusum]

I agree, this is one time that I prefer to be a flakey!