Full mash grain, partial boil

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mrfocus

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Now, I know, before you go calling me crazy (or that this has been asked before, I have searched), let me explain. I cannot brew outside for at least 4 months a year at least. As an example, we've gotten just about 2 feet of snow in the last two weeks, and it's here to stay.

I currently have a 5 gallon brew pot for doing extract and steeping grains.

I would be interested in going to partial mash, but would prefer doing a complete mash (example 10lbs of crushed grain) in a 5 gallon MLT. I would need two 5 gallon pots, one to boil water and one to boil the wort in, right?

Here is what I think the steps would be:
1. Heat the water needed (3.44 gallons is what Beer Smith says) to the right temp (170F).
2. Dough-in with 1 gallon water into the MLT.
3. Add the rest of the water in the cooler MLT for 60 minutes of mashing.
4. Then I can batch sparge with 3x 0.48 gallons and once 0.25 gallons at 168F.
5. Then I would empty it out into the brew pot.
6. Boil as normal.

Now, if this already has been asked before, please forgive me, and thanks for the answers.

mrfocus
 
I'm not sure I understand your process, but your sparge volumes are so low, I wonder what you really will get out of it. I would say to do no more than two sparges and give it a whirl. It seems like the worst that could happen is that you have a small volume of high gravity wort.

If you need to, you could split boil between two pots. I'm not sure if that solves your problem or just adds hassle, though.


TL
 
You could do this, I suppose, but your efficiency will probably be pretty low because your not using enough sparge water. For a 10-lb mash, you'd usually be looking at 5 gal or so of sparge water; you're going to be at about half that. Multiple small batch sparges might help some (I've never tried it), but I have to believe you'll be leaving some sugars behind.

Let's say you hit 60% efficiency (optimistic, I think), and get 3.5 gal out of your partial boil. That's going to give you an OG of about 1.040-1.045 after you dilute to 5 gallons with top-up water. If you're OK with that as a max OG (unless you can figure out how to get more efficiency with that small volume of sparge water), then this will work.

Personally, I'd do PMs, or figure out a way to brew full boils outside.
 
I understand your theory, and I think it will work, but you need to assume that your efficiency will probably be quite a bit lower than normal.

Another option that I've used is to start the boil with most of the wort. Then once the volume has come down from evaporation, start adding the rest of the wort back to the boil. Be careful to add it slowly as it will need to hot break and you don't want to stop the main pot from boiling.
 
Thanks for the quick and great answers.

I just want a clarification, the reason my efficiency would be so low is that I wouldn't have enough sparge water to get all of the sugars out of the grain, right?

What if I did decoction mash. Where I drain part of the mash, boil it and add it back in. I can do this multiple times (2-3). I think that adding back the same wort could possibly get more of the sugars out. Question is, would I use a MLT? If so, I might need a 10 gallon cooler (or I may go for a rectangular one, around 7-8 gallons).
 
Your lowered efficiency would have to do with cutting the sparge short to only about 4 gallons preboil. You'll lose about a gallon to evaporation after 60 minutes for a total of only 3 gallons to put in the fermenter (you could top off with water but that's not the point of all grain brewing). The best option would be to sparge to a full 6.5 gallons and collect it all in a bucket. Then put 4 gallons in your 5 gallon pot and start the boil. If you have another 2-gallon pot, you can boil the residual 1.5 gallons or simply wait until you can fit a little more in the pot as you lose volume.

Simple way of saying it is, in order to brew all grain efficiently, you must collect at least 1.5 gallons more wort than your finished batch size and boil it down to concentrate. You can still do it by putting a ton more grain in, pulling a heavy first runnings (no sparge), boil that, then top up. You'll be wasting about $10 a batch doing that and you might as well buy 3 pounds of extract instead.
 
I'm planning on doing my Berliner Weisse as a "partial boil AG," but I can get away with that, I think (haven't done it yet) because it's such a low gravity beer (1.032). You might be able to get away with doing an ordinary bitter or something like that, otherwise, it'll be tough to pull enough sugars out of the grain for most styles.

Why not do partial mashes? Perfectly good solution for your circumstances. You get to use all the "cool" grains, you get fresher-tasting beer, can brew essentially ANYTHING, and can do partial boils.
 
the_bird said:
Why not do partial mashes? Perfectly good solution for your circumstances. You get to use all the "cool" grains, you get fresher-tasting beer, can brew essentially ANYTHING, and can do partial boils.

I think I may do that.

Anyone have opinions on the decoction (which I don't believe is a very popular method)?

Thanks
 
You won't get much more sugar out. You basically have it all suspended already prior to the first runnings especially if you stir. Elevating the temp and adding it back might pull another 1-2% efficiency but that's probably less than a $1 for your effort.
 
doing a decoction isn't what you want to do. you're just using the wrong term. a decoction mash involves removing a portion of the full mash, grains and all, and boiling it to raise the temperature of the mash. i think what you're talking about, and what might work for you, is to do a reiterated mash. this involves using your first runnings from your mash to do another mash in another grain bed. this just allows you to make really really high gravity beers with out either using insane amounts of grain or boiling a ton of wort for a really long time. in your situation, you'll be able to get a high enough gravity to be able to dilute it with water in the primary so that you'll have the gravity you want and you won't have to boil forever. there in an article in the current issue of Brew Your Own that outlines this technique, might be a good read.

i do AG full boils with a 5 gallon kettle for 3 gallon batches. if you don't mind having a smaller batch this would be a great way to get into AG, figure out your process, etc. my starting boil volume is 4.75 gallons.

i guess it comes down to whether you WANT to do all grain brews or you WANT to brew 5 gallon batches. you can't do both unless you sparge your extra runnings into a bucket and add it as you lose volume.
 
I did a split batch of a partial mash, which let me use 2 different yeasts .. came out better than I expected ..

Allowed me to do a concentrated boil (7 gal) and divide between 2 buckets

I have not done this with AG - it seems like I wld be defeating the purpose of AG to top it off ..
 
and a 5 gallon cooler MLT. I heat about 7 gallons in my pot, and boil another gallon on my stove top to preheat my MLT. Dump my mash water and during the hour mash, heat my lauter water to 175 and transfer to a spare 5 gallon cooler. First mash runnings go into the now empty pot, lauter water from the spare cooler into the MLT & then added to the pot.


Works for me until I get the keggle and 10 gallon MLT. May still use it to brew indoors.
YMMV
 
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