Small brewpot/small MLT concerns

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STAD

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Stupid question:

I'm currently doing extract with steeped grains, boiling my wort in a stock pot. I think that produces about two gallons of "concentrated" wort which is combined with three gallons of water to create five gallons of wort that I then pitch and ferment.

If I were to go all-grain and end up with a five gallon batch, would I create 11 gallons of "malted water" which then needs to be boiled down to 5 gallons of wort and doesn't require any further water addition?

I am confused about this as well. I have a 7.5 gallon brew pot and realized that I can't really do anything with over 8.5 lbs of grain (if I have done the math correctly). Even with a small grain bill of 8.5 lbs, I calculated that you need 6.91 gallons of water. What use is a 5 gallon mash tun for batch sparging? I planned on buying a 10 gallon, but it seems worthless given that I only have a 7.5 gallon brew pot. Am I going to need more?
 
I am confused about this as well. I have a 7.5 gallon brew pot and realized that I can't really do anything with over 8.5 lbs of grain (if I have done the math correctly). Even with a small grain bill of 8.5 lbs, I calculated that you need 6.91 gallons of water. What use is a 5 gallon mash tun for batch sparging? I planned on buying a 10 gallon, but it seems worthless given that I only have a 7.5 gallon brew pot. Am I going to need more?

No. What some of us do is "give up" a little efficiency to make our volume. What I mean is this- say I have a 10 pound grain bill. I mash with 1.25 quarts of water per pound, so that's 12.5 quarts (3 gallons m/l). The grain will absorb about .1 gallon/pound so the first runnings will be 2 gallons. Since my boil volume is 6 gallons, I only sparge with what I need to bring me up to 6 gallons, or 4 gallons more. I split that sparge into two additions, so two batch sparges of 2 gallons each. Now, I will get a lower efficiency by doing that. But that's ok with me. I could sparge with 5 gallons (.5 gallons per pound) and boil down that extra gallon for greater efficiency. But, I also have a small brewpot and I don't really want to boil an extra hour (my boil off is less than 1 gallon per hour) just to have greater efficiency.

So, unless you have a really large grain bill, the 1.25 quarts per pound mash and up to .5 gallons per pound sparge will work.

If you want to know in advance how big of a beer you can mash in a 5 gallon cooler, check out this mash calculator (about 1/2 way down the page) called "Can I mash it?": Green Bay Rackers--Mash Calculators
 
Good post, Yooper.

Just as a rule of thumb, I know that 12 lb of grain at 1.25 qt/lb mash thickness is about all I can mash in my 5 gallon cooler. At my usual 75% or so efficiency, that ill make beer in the 1.060 OG range.
 
But my question is more regarding the brew pot. It looks like I'm going to have to go bigger if I wanna do anything over over 12 lbs, right?
 
But my question is more regarding the brew pot. It looks like I'm going to have to go bigger if I wanna do anything over over 12 lbs, right?

As far as I'm concerned, your kettle can't be TOO big. Well, not really.
I use a converted Sanke keg that holds 15+ gallons when full. I brewed a batch yesterday with 12 lb of grain and 8 gallons pre-boil. Here's what it looked like after the boil:
brewday_032.jpg

See the hop leaves all the way up the sides? I nearly boiled it over.
You can use a smaller kettle, but you have to watch it carefully. A spray bottle full of water helps knock down foam, and by using Fermcap drops, you can virtually eliminate foaming in the kettle.
 
But my question is more regarding the brew pot. It looks like I'm going to have to go bigger if I wanna do anything over over 12 lbs, right?

No, I thought that was the question I answered! I guess I'm too "rambling". You can make a smaller boil volume. However, you're giving up more efficiency that way. I never boil over 6.5 gallons- my brewpot is too small. You will short yourself on a sparge, so you won't get the best efficiency. But it can be done. You're more limited by a 5 gallon MLT than the size of the boilpot.
 
No, I thought that was the question I answered! I guess I'm too "rambling". You can make a smaller boil volume. However, you're giving up more efficiency that way. I never boil over 6.5 gallons- my brewpot is too small. You will short yourself on a sparge, so you won't get the best efficiency. But it can be done. You're more limited by a 5 gallon MLT than the size of the boilpot.

You may have very well answered the question. It's been a long day at work and I've been crunching numbers for hours so they are kind of all blending together. I was confused with that "Can I mash it?" They are giving me different calculations than what I am calculating.

Let me try to get specific (I'm pretty much an idiot right now so bare with me).

Lets say I want to do a brew with a 14.5 lb. grain bill. I have a 10 gallon mash tun, but a 7.5 gallon brew kettle.

Using 1.25 quarts per pound, I get a little more than 4.5 gal. of water needed to mash. So I would then put the grain and hot water in the mash tun (beverage cooler) for the required time.

Then when it comes to sparging, I would just sparge with enough water to reach 6 gallons? Is that going to be enough? I guess I just want to know what I'm limited to if I get a 10 gallon mash tun, and keep my 7.5 gallon brew kettle.

**Also, if I'm way wrong, it's because I have never done AG and am still trying to teach myself.
 
Lets say I want to do a brew with a 14.5 lb. grain bill. I have a 10 gallon mash tun, but a 7.5 gallon brew kettle.

Using 1.25 quarts per pound, I get a little more than 4.5 gal. of water needed to mash. So I would then put the grain and hot water in the mash tun (beverage cooler) for the required time.

Then when it comes to sparging, I would just sparge with enough water to reach 6 gallons? Is that going to be enough? I guess I just want to know what I'm limited to if I get a 10 gallon mash tun, and keep my 7.5 gallon brew kettle.

**Also, if I'm way wrong, it's because I have never done AG and am still trying to teach myself.

Well, yes- but you CAN'T fit 4.5 gallons of water + 14 pounds of grain in your cooler. So, you're more limited by the amount of grain you can mash. (If you look at the "can I mash it" calculator, that would take up 5.5 gallons of space). So, even if you could do it, you'd drain off 3 gallons or so of wort, and then just sparge with 3 gallons to get to your volume. Your efficiency numbers wouldn't be great, but it's doable IF you can mash that much grain.

(I'm breaking this into a new thread- we took this way too far OT and it'll get lost at the bottom of this long thread.)
 
A spray bottle full of water helps knock down foam, and by using Fermcap drops, you can virtually eliminate foaming in the kettle.

I use 5-Star Kettle Defoamer 105, four drops in 6.5 gallons into my 7 gallon pot.:cool:

It seems to carry through its foam-killing ability into the fermenter; the kraeusen ring only climbs up about an inch up the bucket, and I still get great head.
 
...
Lets say I want to do a brew with a 14.5 lb. grain bill. I have a 10 gallon mash tun, but a 7.5 gallon brew kettle.

Using 1.25 quarts per pound, I get a little more than 4.5 gal. of water needed to mash. So I would then put the grain and hot water in the mash tun (beverage cooler) for the required time.

Then when it comes to sparging, I would just sparge with enough water to reach 6 gallons? Is that going to be enough? I guess I just want to know what I'm limited to if I get a 10 gallon mash tun, and keep my 7.5 gallon brew kettle.
...

Sure, you could do it that way. What you'll probably find is that your efficiency is lower than expected -- meaning you may not hit the target OG. Since you're not able to rinse as much sugar out of the grainbed, you'll leave more of it behind, resulting in less sugar in the kettle.

I don't necessarily see that as a problem. I think a lot of people strive for really high efficiency, and that's cool, but I think it's more important to hit your target gravity. If you get your process dialed in and repeatable at 60% efficiency, you can tweak any recipe to match your process and give you a final product that is what you intend.

I did my first full-boil extract batch and my first AG batch in a 7.5 gallon enamelware pot. It worked, I made beer, and it was pretty damn good beer. I've since moved up to a keggle, and it works better.

Honestly, there's so much variation in equipment and processes that anybody's first few batches will require some adjusting and refining of technique. I say, jump in, brew a batch with what you've got, and see how it works for you. Even if you make something a bit different than what you were aiming for, you'll still have good beer to drink while you think about the next batch.
 
I can say from experience you can do at least a 13.5 lb grain bill in a 7.5 gallon brew pot. I was low on efficiency and had to carefully watch the boil(it boiled over several times) but the beer was good and to me thats what matters.
 
If efficiency is important and you use a 7.5g brewpot, then you could collect more wort than your kettle can handle and boil the excess on a separate burner, adding it to the main kettle as it boils off. To me this could be a PITA but could be necessary if you aren't getting great efficiency to begin with.
 
I use 5-Star Kettle Defoamer 105, four drops in 6.5 gallons into my 7 gallon pot.:cool:

It seems to carry through its foam-killing ability into the fermenter; the kraeusen ring only climbs up about an inch up the bucket, and I still get great head.

Does this leave any off flavors? That description makes me worry... Sounds gross, and possibly harmful.
 
Let's take it from another angle. Start with your desired volume into the fermenter.

If you want 5.25 gallons in the fermenter, now decide how long your boil is going to be. Pils malt? 90 minutes. No pils malt? 60 minutes. Now you have to guess what your boil off rate is going to be. It should be somewhere between 1-1.75 gallons per 60 minute boil. Let's be conservative and assume you don't have any pils malt in your grain bill. Figure a 60 minute boil with a boil off of 1.25 gallons. So, a little simple math says that 5.25 + 1.25 is 6.5 gallons. You must sparge until you have 6.5 or you'll come up short in the fermenter.

It's still going to be hard to boil with vigor with only a gallon of headspace. I'd boil 5.5 in that pot and do the other gallon in another pot until you have room.
 
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