How to Malt at Home: An In-Depth Guide

I found the foundation for my malt kilning drum in the form of two inexpensive 2 quart sauce pans from Family Dollar @ $7 each. About 7.25" OD. My criteria was for something under 8" diameter which is my approximate space. They have that disgusting material on the inside of them.... teflon or "teflon II"........... I just absolutely loath the stuff and use only cast iron or stainless steel, but it shouldn't matter here. I cut the two of them off about 1.5" tall, and will drill a 3/4" diameter hole centered in each one on the lathe. One end will have a 3/4" hub bolted to it. The two will be connected together by 3 threaded rods out near the edge. There will be a center plate that will bolt to the opposite end with a 3/4" hole in it. A 3/4" shaft will span the width, and have a piece of 6MM key stock pressed into a hole in one end, the other end turned down to drop into the rotisserie bracket on the non driven end. To fill it, the plate will be removed, then bolted back on... same to remove it. The entirety will be wrapped with suitable screen, drawn down tightly using double wrap industrial band clamps. You draw them up tight with a special tool (which I have), then bend the cut end over. Very powerful clamps.

I intend to cut an opening in one side of the oven where the control system is, and cover it with a removable aluminum plate. Rather than adding switches, I'll probably wire the roto to run with the convection fan. Eventually I'll probably add an STC 1000 temp controller right on the side.

This spawning all kinds of ideas for a single stand alone machine that will soak, sprout, dry, and kiln...... a "Pico Malt" if you will. Imagine a machine you could program with your smart phone. Using the built in scale, you'd record your initial weight for future dryness reference. The drying and kilning profile would be programmable. you'd have to visually examine the condition of the grain during the soaking and sprouting stage, but after that you could specify the drying and kilning temp, time, and moisture curves to achieve a precise result.


H.W.

 

Yeah you're getting pretty far from any conventional brewing method here, but hey, why not. One thing that I don't understand is what the amylase is going to do in the fermenter. Typically, conversion would have happened before the boil and then the amylase would be denatured by the high temps. But you're changing the order around. So instead of having all the yeast food ready by the time you pitch the yeast, are you thinking the amylase will break down the starches into sugars in the fermenter which will then be immediately gobbled up by the yeasties?

 

Typical Saki and Rice Wine production depends on ongoing conversion during fermentation. It's a simultaneous process. Of course this involves fungal amylase from the aspergillus fungus, rather than amylase produced from sprouting grains. AG 300 is not the typical powdered amylase you buy at the LHBS, rather it is a liquid product produced from aspergillus. Right on the bottle, it recommends adding it to the ferment........ and I quote:

"Works effectively at fermentation temperatures. Add to wort at or near the start of fermentation. Up to 95% of the starch can be converted to fermentable sugars"

H.W.

 

Yesterday I wired up my cheap convection oven. I cut the side open, and disconnected all the controls except the timer. I mounted two toggle switches on the front panel. The lower is for the convection fan, the upper for the rotisserie. I bolted an STC 1000 to the top, and mounted a large open contact relay I had inside on the back. It's wired now so the timer is the on / off switch.... as before. It applies power to the toggle switches, and to the STC 1000. The thermocouple for the STC 1000 extends into the plenum where the convection fan circulates the air from bottom to top in the oven, and controls the relay maintaining what I assume will be a pretty constant temp.
The whole thing is pretty "sanitary", though if I were to do it again, I would remove the temp control and the function selector, and put an aluminum panel there with my switches. I'm also considering installing a switch that allows me to run one or both elements.......... or setting it up for series or parallel. In series the elements would put out far less heat, and this would perhaps be ideal for drying. This would be 25% of the heat output and power consumption........ "low density heating".... low intensity.
I still have to manufacture my perforated aluminum cover plate. It of course is obviously "hacked", with the two toggle switches and the STC 1000 controller. I could have removed the entire face plate and replaced it with a circular burnished aluminum plate with nice rocker switches attractively labeled, but the STC 1000 needed to be on top away from the heat, or fan cooled inside. There is an inside cooling fan but not large enough to make me happy. It's also difficult to make rectangular holes neatly. I'll live with "hacked"

H.W.

 

Low intensity heating is indeed ideal for drying. We usually start kilning around 120 F to remove the bulk of the moisture, then gradually ramp the temp up to the final curing temp for the last couple hours. Curing temp can vary widely between 176-221 F depending on what kind of malt you're making. Then there's roasting temps...

What temps can you hit in your oven? Are you planning to roast in there?

 

I haven't tested to see what temps it'll hit, but it will clearly far exceed those figures. I wired in a DPDT switch today, and had a bit of a train wreck with both motors. While trying to pull off the slide on spade connectors, I managed to break the spades loose from both motors. I had to pull them out and carefully solder to the wires which are smaller than a human hair, and then epoxy things in place....... What a pain!! I probably won't put things back together until Thursday.
I did get the series / parallel working and tested it. There is a HUGE difference between series and parallel. Amps measure out at 25% in series approximately, and my infrared heat gun shows the elements in series only reaching about 300 on each of the 4. In parallel, it jumped up to over 1000 before I switched things off. Clearly with 4 rod elements each radiating heat away from 1200F or so surface temps, it will put heat things pretty hot inside that small space. In series it will be pretty well suited for drying, etc. I think the whole thing should work out pretty well.

................... A touch of spring madness maybe ;-) Who but me buys a new convection oven and immediately butchers it up? I'm pretty pleased with the STC 1000 and contactor setup. I haven't yet had to buy anything except the oven itself...... all the rest was from my personal collection of "junk", including the STC 1000.

40 years of not throwing anything away ;-)

H.W.

 

A tad behind schedule, I finally got both the damaged parts working, the fan motor and the rotisserie motor. Both presented very difficult soldering jobs, and one took 3 tries. They are altogether to delicate!

Everything functions as it should......... completely under my control. I have switches for the rotisserie, and fan, and a high / low switch for the element that shifts from parallel to series. The STC 1000 probe is in the plenum, and operates the contactor properly. I don't have an oven thermometer to verify internal temps. It's next on my list.

I will do some lathe work today at a friend's shop so I can assemble the screened drum. I have the two ends, cut from dollar store sauce pans, the shaft and hub have to be machined, and a template to drill matching holes for the threaded rods (which I have), and a removable end must be built. And of course the screen attached.

H.W.

 

I've completed my kilning setup. The countertop convection oven has been modified to operate the way I want it with control of the fan and rotisserie as well as an STC 1000 temp controller driving a contactor, and my series / parallel element switching. I have my rotating screen built, which turned out to be a bit of a project. I bought two sauce pans at the dollar store for the ends, made a drive hub from a pulley drilled everything, and set up spacers made from 7/16 threaded rod, wrapped the works with aluminum screen, glued in place with epoxy, and then screwed through the epoxy saturated areas screen, with screws about 1.5" apart. Stitched and JB weld sealed the ends of the screen...... about 3 wraps. One end has a removable cover held on by 3 screws.


My conclusions after this build, which was intended for my own very small scale brewing....... about 2 gallons a week, are perhaps worth relating here.

Screened drum for kilning...... a waste of time, as is the oven itself.

I envision a completely different device for larger scale...........


H.W.

 

Yeah, kilning drums are tough to pull off on a small scale. I've been happy with a stationary grain bed during kilning - makes things a lot simpler.

 

I would agree with that......... This one is capable of 5 pounds of grain and works quite well. The liability is that you cannot examine the grain easily. It needs an access door I can reach without removing the drum....... The next project.

I also intend to install a fan and heating element to blow back to front through the oven with sufficient volume for drying so I can crack the door and flip the dryer system on.

The system is a bit too small to be practical, but I'm learning from it, and that's worth something........


H.W.

 

My first full scale (10 lbs) malting project failed......... This AM, I intended to move the grain onto the drying screen...... and drum. The sprouting was successful and at about the right stage. Unfortunately the ends of many of the grains had started to mold. I believe that the problem was too much moisture. The bottom of the plastic tote most of the time had a thin film of liquid when I stirred the grain. Next batch I will approach a bit differently. The problem now is how to kill any residual mold spores in the tote.

I knew I had too much moisture, and should have taken a sponge to it...... Oh well, live and learn. 10 pounds of barley wasted ;-(


H.W.

 

Hey it's 10 pounds of barley that won't become beer, but not 10 pounds wasted. Now if you made the exact same mistakes again, that would be a bit of a waste.

You get mold if you don't have proper climate control. It's partly a function of moisture, but the germinating grain should be kept moist, so you can't totally change that variable. Most likely your germinating temps were too high. What was the ambient temp in your germination space? And were you taking the temp of the grain bed? The respiring grain is putting off quite a bit of heat, so it can get quite hot at the center of the grain.

 

Thanks for starting this thread. I'm just getting into the malting thing but have been homebrewing for many years. Finally have the time to try some of this stuff. My goal is to have an estate grown beer which means everything comes from my property. I'm located in western Washington and hops and barley grow well here. I've got space to grow a couple hundred pounds of barley but not sure I want to do that much. Hops were planted years ago.

I planted about 32 sqft in a raised bed to Conlon barley from johnnys seeds and they are growing. I plan to prepare a bed to grow maybe 100lbs for next year.

I have a climate controlled garage I can keep at 60f all summer but plan on doing most of this in cool weather so the humidity levels are high.

I'm pretty handy with most things but do not want to build a kiln from scratch. I'll probably just get a nice dehydrator.

I picked up a few lbs of red winter wheat at the store and malting it now. Surprisingly easy do far. But I really want to do some barley. While WA state grows a lot of barley it's mostly grown 4-5 hours away near Idaho. Does anyone know if there is a source of unmalted barley in western washington?

Thanks and keep up the good work!

 

I live in MN so I don't know barley farmers out in western WA, but I can tell you that there's a craft malthouse near you called Skagit Valley Malting. You could ask them where they get their barley.

Love the estate beer plan! Sounds like you're on the right track.

 

I found a feed store in the Skagit Valley that sells barley at $10 for 50lbs. I'm going to give that a shot until I can get my estate barley field up and running. I don't want to screw up the barley I grow!

 

There was a very extensive home malting post here at HBT front page recently if you haven't seen it. http://www.homebrewtalk.com/adventures-home-malting.html

 

Starting this today with 1.85 pounds of rye and 2.37 pounds of barley for a micro (1 gallon batch). Wish me luck!

 

I'm waiting for things to cool off a bit before I try malting again. I have 40lbs of wheat I'm going to try.