Malting and kilning rice

Hey guys, I was thinking of pulling a page out of the sake brewers handbook to make a GF beer. One thing I did notice is that in many methods for homebrew sake, they will malt the rice, then right away add koji-kin (which to me sounds like a mold with some kind of beta-amalayse enzyme).

So, I was figuring that I would change things up a bit form most of the sake stuff but wanted to get your thoughts.

After malting the rice (creating komi-koji), do what a typical maltster would do and kiln it in the oven, but try and get some darker roasts. Maybe try this with different brands and styles of rice (like brown rice) to get some really dark roasts for a stout, then do a mini mash with koji-kin.

I already have a sorghum syrup to work with for the base, so I'm wanting to create more specialty ingredients to round out the flavor and darken it up.

Has anyone else tried this? Bad idea? Good idea? Thoughts?

There was some confusion on my end about "malt-rice". This is not malted rice like we would malt millet, buckwheat, sorghum etc. But rather steamed rice innoculated with koji-kin, which is called komi-koji. I suppose "malt-rice" is some sort of translation.

I've seen a few references to the possibility, not so much the kilning part, but the most interesting bit is that koji enzymes do seem to be the enzymes used to make gluten free brown rice syrup. (Non gluten free would be using barley enzymes). And because we use brown rice syrup already, it seems plausible that you can take a step back and use it directly. Quite possibly use the kome-koji, or the koji-kin directly on a different substrate as well, since they use kome-koji on different starches for the same result.

(For example, try using it on sorghum instead of rice to convert the sorghum. It's likely though, that this is how it's already produced).

http://www.taylor-madeak.org/index.php/2008/02/29/how-to-make-sake-at-home-a-taylor-made-g

I've been waiting until I can get a temperature controlled heatpad, or at least a cooler for humidity and heat before I ventured into any of the sake items.

I think it's a good idea to venture into. Another idea may be roasting the grains first, then steaming and innoculating with koji-kin, if that's a possibility. Or using the kome-koji as the enzyme source (so reguar rice and koji-kin) to different roasted grains to create the alpha and beta enzymes and convert the other grain starch. (http://homebrewsake.com/home/2011/03/13/koji-production-–-what-are-we-trying-to-do/)

Those two sites are generally the most referred to for sake.

Those links are great! Thanks. I was thinking about doing a roast first like you mentioned before steaming and the like. Possibly even doing the same to a brown rice. I have about a month and a half before I need to brew the beer, so plenty of time to study and experiment. Might even brew a sake while I'm at it...

For converting the starches, I was thinking, rather than using a heat pad, get one of those cheap styrofoam coolers, have the rice convert in there, but periodically replace cups of warm water inside. This way you keep the humidity and temperatures fairly constant, given that you might only lose a degree every hour at most.

Welcome, I've been reading them for a while myself since I saw them from here.

The problem is that there's a certain optional portion in regards to the koji kin reproduction of spores that requires a dry heat. Not a moist heat. Or at least that's what's suspected and I haven't seen any comments that say otherwise yet. I rather suspect that it is the case, since that seems to be how the mold that grows on anything else around here works. This wouldn't be necessary for the actual production of the kome-koji of course, but would help to get more spores. http://www.popsci.com/science/article/2011-05/how-fungi-launch-spores-no-longer-mystery

It's this extra step that I wish to do. http://www.taylor-madeak.org/index.php/2008/10/17/growing-koji-for-homebrewing-sake. At the moment, I'm just trying to save up for it. You know how it is, you start saving up for the sake equipment, but you turn around and spend it on another keg, or malting equipment, or faucets, or another wine kit.

Oh, in addition, we of course would use rice flour, instead of regular flour, for the spore spreading process.

I suspect that I'll probably just try making a sake using a less polished rice to try it out, and do the spore production later. Like we do with yeast, buy it, use it, and don't reserve it for the next batch until we finally get around to doing that.

I'll throw this one by you to see if I'm getting this right.

Koji-kin is a mold that will essentially 'infect' rice and provide essential amalayse enzymes for the conversion of starches into sugars.

In order to convert rice, koji (the infected rice) can be 'mashed' with regular steamed rice to convert those starches into sugars.

Knowing that, I am guessing that after conversion (provided yeast wasn't used as part of the process), you can kiln the rice to eventually caramelize the sugars, and either use increased heat or longer low heat kilning time to affect the proteins in the rice, causing them to darken.

I would guess this process would allow you to create what essentially amounts to a dark crystal rice.

As far as I can tell, Koji is pretty much various enzymes. Not much else.

From what I can tell, though I have no experience, I think that the entire conversion process is a mash, similar to a grain mash for beer. This would be before yeast is added. And in this process, rice doesn't have a lot of structure to it, so it pretty much liquifies and becomes a goo. (Page 7, first few steps of the taylor made guide)
First is the initial mash of the koji and plain rice, and on the next step he adds the yeast because throughout the next week, it's a continuous bulking of the mash, and if the yeast wasn't there, something else would likely take hold.

If we didn't use the yeast but did something similar, we'd still end up with a pile of sugary goo, which is what I think they wind up using for the brown rice syrup. I'm not definate on that since there's not much info about how they do it, but I expect something similar.

It that week-long step where I would actually expect that we could add additional unmalted grains of a different type for conversion. Instead of adding rice, we could use roasted sorghum or roasted buckwheat.

Not that they don't grow the koji on other things like soybeans to make soy sauce or miso, or some other things that I can't look up because my computer needs a reboot. So we could grow the koji on sorghum, and then add buckwheat, or something like that.

I'm honestly thinking that we would have better luck malting sorghum and buckwheat, making a crystal malt from that, and mashing it with the weeklong koji process. Hard to say though.

Our best thing to do right now, is to make a batch of sake and see how it looks

For sure. I think I'll probably brew sake anyways. I have sorghum syrup to work with, and I was thinking of other ways to get darker grains and try to give a GF beer a more roasty flavor. I'll have to take a look at some other stuff.

In the mean time, I did pick up koji and sake #9 yeast, so I should start planning my sake brewing. I'm thinking of trying to polish some rice first.

You'll have to tell us how you're polishing it. I know that theres a place selling milled sake rice https://www.fhsteinbart.com/products/index.php but I haven't seen home polishing yet. FHseinbart buys it from SakeOne/Momokawa (Verified by Greg Lorenz

I hear it is tricky but possible. You can use something like a rotating drum to do it, like you might with rock polishing, but because rice grains aren't really heavy enough to polish each other, you need to do it with speed to force the grains to collide.

That's what I had seen in the various sake threads since you had mentioned it and I dug around. I didn't see much about polishing methods other than using large machinery, even for the "home" rice mills. And that it requires a high speed.

One possibility that I had considered, but don't know if it's plausible, is to use a cyclonic system or fluid air bed system. If the cyclone is right, then the grains of rice should swirl around the outside abrasive surface (rather than a smooth surface), and the grains would stay in the cyclone cylinder and the finings/dust should either be caught into a filter, or exhausted from the sytem.

In other words: take a *clean/new* Dyson vacuum, put some fine metal screening around the cylinder (or even not) and toss some rice in and see what happens. If you have even a less powerful bagless, and you don't empty the canister too often, you see things becoming a powder eventually as it cycles around and around.
Alternatively, compressed air driven into an aluminum duct could potentially work the same way.

I've actually considered doing a similar system for derooting grains, but I have to work on malting before I want to try that.
Also thought of building a system so I can roast more than 3 oz of coffee. They all have a similar airflow design, it's just that the coffee relies more on heat, and the others rely more on air velocity.

The main issue would be that it's still going to be a rather large device (any of those three), and likely won't be able to handle much capacity.

I'm just going to use plain Koshuko rose rice for my first few, then get the online, and I suppose if it ever goes further, I can look into that. Honestly, my first one build will be the coffee roaster. My money has been going to beer though, so it's been postponed for a while.

I seemed to have trouble with temperature regulation on my first batch of koji, so I'm trying it again to see if feels like it's coming out right. I haven't tossed the first batch and I'm letting it continue in a different container to prevent any unwanted cross contamination.
I'm starting up another batch. This one I'm going to keep outside in a cooler (in the shade) since the temperature is around the target of 96ish, rather than inside where I keep it at 78-80. This way the temperature drop should be less.
It does appear that it could be possible to kiln the koji if wished. It seems dry enough. So the slurry that I've looked at has to do with the actual mash (like any ordinary grain mash.) The enzymatic properties and temperatures would still apply.

Thanks for the update. I still have to get around to doing something with my koji and Sake #9 yeast. Best of luck with your stuff though.

Update #2. Tossed the first batch. It was definately not smelling right. Second batch overshot the mark and I think it's about to start sporing. (Yellow/green from the koji, so it can't be used for any enzymatic conversions)

So yeah.. while it's not necessary to get a temperature controller involved, it's going to be much easier with one in order to keep both the temperature in the 5 degree range necessary for growth, plus to maintain the humidity needed. Plus I'm going to make sure the second 24 hours is on a day off, so I can check more often on it. I might have enough time to try fitting it in on Saturday, otherwise I'm going to wait to get a temperature controller and a heat pad.