Direct heat step mash - info for first-timer.

Since I am moving by a buddy who also brews, and has a nice keggle, I thought we could probably use my 8 gal brew pot as a mash tun. This would allow us to do a step mash fairly easily, I think (we each have a burner). Is there anything more to it than just heating and stirring gently until I get to the target temp, then turning the burner off when the temp is right, waiting, and heating to the next step? Should I still use about half the water in the mash and the other half as sparge water? What styles would benefit from this? My guess is that this would be most beneficial for a lager or a wheat beer. Does anyone have any tips for brewing this way? I have previously just done the denny-tun method of brewing.

Stir the whole time!  Scorched grains don’t taste good (ask me how I know)–unless you really like “Quesadilla” Beer.  Also, it is possible that your SRM’s may bump up a little higher (especially if you’re doing a light colored beer).  I just brewed a wheat beer this way that should have been around 5.5 SRM, but ended up around 7.5-8.0 SRM.

Have fun brewing with your buddy–it is much more fun to brew in groups.

My converted kegs have false bottoms.  The grain is not in contact with the bottom,  You should recirculate when the fire is on, to distribute the heat, and if any small grains bits get through they don’t get scorched.  A pump is really a good thing to have for hte recirculation.

+1 stir when the heat is on.
Be gentle with the heat too.
Mash in fairly thin too

All this will help you.

We’re doing one Thursday with this method

I’ve found that it’s a good idea to turn the heat off when you are still a few degrees below your target temperature. Otherwise, it is very easy to overshoot (at least that has been my experience).

Yes, it certainly is

Easy to put heat to it again if need be

I mash everything over a direct fired kettle/tun. I’ve used mine enough to know if I set the flame very low and barely kissing the bottom of the tun and stir diligently as soon as the temp I need is reached I need to turn off the flame immediately, but still stir for another couple of minutes. The suggestion to stop a few degrees early the first time out is sound, once you know how your setup behaves you can tweak your procedures.

As far as water, go with at least 1.5 qts/lb to make stirring easier, or if you batch, you could do the half thing. I drain my first runnings and then fly the remainder, but you can do it any way you please.

Unless you want an exhausting upper body workout, make a mix-masher, use a heavy duty drill with a paint mixer, or recirculate with a pump. I’ve done all three and the mix-masher is the easiest.

http://schmidling.com/mix.htm

I think what method you use depends on whether you have a false bottom in the pot or not.

If you do have a false bottom, keeping the heat on low and recirculating is a very even way of heating.  It’s sort of like a manual RIMS except the heat is applied to the mash tun rather than the recirculating loop, but the effect is pretty much the same. You still have to stir to get the even heating, and it helps to have a more liquid mash. The downside is that stirring the mash can make it harder to recirculate, so be careful about disturbing the grain bed too close to the false bottom.

If you don’t have a false bottom, you’re essentially doing a decoction. So you definitely have to stir, and you will likely get some color development. A thinner mash is better, since it will keep it from scorching. Use a metal spoon so you can feel the bottom of the kettle for any build-up, which can scorch. A scorched mash tastes like an old ashtray.

German mashes tend to be thinner than English mashes since they often pump them around. It might just be easier for you to start thick and just use boiling water infusions.

If you are going to step mash in one pot without a false bottom and with direct heat, I’d use a relatively thin mash, maybe add some rice hulls, add the heat slowly, and stir constantly. It’s important to get the heat evenly distributed, so you’ll have to be stirring in a way that mixes the layers (think about making the grain on the top coming into contact with the bottom of the pot). Try to avoid whipping excessive air into it while you’re doing this. Keep stirring after you kill the heat; the bottom will still be hotter, and the temperature will continue to rise (like carry-over cooking with meat).

I direct-fire my mash tun (started last year).  A pump is handy so you can recirculate AND stir.  I started by using a 1-gallon pitcher, but found that I needed to recirculate more than I initially expected and needed to be really patient.  My first batch I was not pulling the liquid off fast enough and supe-heated the wort under the grain bed…nothing scorched, but I wound up with a less fermentable wort than desired.

I still have found that patience and low heat are critical to not over-heating the mash.  Over the course of the last year I’ve upgraded my mash tun and now use a pump connected to an AutoSparge for my recirculation.  I am pretty happy with that set-up as it worked out on my last batch.

This would be my recommendation.  In my opinion, it is easier to hit your temperatures using infusions.  The only direct heating I do is for mashout.

I disagree entirely with you wit…I can hit my temp each and every time exactly regardless of whether I am mashing a 5 gallon batch or a 10 gallon batch a low gravity or a high gravity. I could NEVER get it that exact with infusions…YMMV

Go ahead disagree.  To me it is still easier to add the infusion and stir for a short bit than to sit over the mash tun, stir and or circulating, watching the thermometer.  I have my system well calibrated and know what my end temperature for each mash step is so I can calculate the exact amount of water to add.  People have been very surprised how accurately I hit my temps.  Like you said YMMV.

I did, see above  ;)

Perhaps someone of experience can do it, but far too often I see posts like this
http://www.homebrewersassociation.org/forum/index.php?topic=3303.0
and the subject of this thread is “info for first-timer”…

MMDV…My mileage does vary!  I can hit really exact temps with careful infusions of boiling water.

I have found it very perilous to hit various steps with infusions. It often ends up using way more water than I had planned on, and is very time-consuming. Now, I rarely ever use anything but a single infusion, so the problem is generally moot, but I thought direct heat would be worth a try since, by combining our supplies, my friend and I can accomplish it fairly easily.

I do not have a false bottom, but I have a kettle screen (like a bazooka) on my kettle (which, in this case, would be the mash tun). So I guess I will have to mash super-thin, and use a lb or so of rice hulls. I suppose I will go for a wheat beer or a lager when I brew this one, since I can’t really think of what else would particularly benefit from steps (maybe an altbier? a dubbel?). I mostly brew American and British styles, so I just do single infusons (I don’t even bother with a mashout).

+1 - in fact I am usually spot on and never varying more than a degree or two. I would also ask myself whether or not a step mash is going to be really necessary. For most beers a single infusion is perfectly adequate. I single infuse my alt and dubbel with great results.

Well, that’s not entirely true, I add a portion of boiling water to the alt to raise the temp to 158 for 20 minutes.

I’m building a RIMS system and all of the research that I’ve done indicates keeping the grain off the bottom of the pot using a false bottom and recirculating the wort is the most practical and consistent means of mashing if using direct fire. YMMV.

I have been a batch sparger for many years using a single infusion in a cooler and will continue to use it as needed,  I really like the simplicity of batch sparging but I want to automate my process so I am using a RIMS.  I am in the process of finishing my Brutus stand.

If you can possibly buy a false bottom for your pot, I would do it right away.

Well, which is it? Spot on or varying a few degrees, sounds like the latter which is certainly not spot on. I can hit it dead on every single time and probably could get it to a half degree if I cared to. In reality it really doesn’t matter that much, most brewing came from places using Celcium and a single degree Celcius is a couple of degrees Fahrenheit, but I hate it when someone speaks of being precise when in reality they are not.  :wink: