AG with a 4 gallon boil but a 5 gallon batch size

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Skelator

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I've done a couple PM batches and I'd like to step into AG (so cheap!!) however, i only have one 5gal pot and one 5gal cooler to use as a MLT. The recipe im looking only calls for 10.5 pounds of grain which will fit in the MLT.

My problem comes up when we get to boil size, I can realisitcally only boil 4 gallons then add water to it when i put it in primary.

I've been using hopville.com's recipe calculus where it adjusts for batch and boil size. So i guess my first question is "Has anyone else brewed an AG with a 4gal boil?"

This now begs the questions, "how much water do i use for mash AND sparge since boil size is only 4 gallons?" "Is it wrong to mash with 2.5 gallons and sparge with 2.5? (yes 2.5+2.5=5 but im guesstimating i'll lose about a gallon to grain absorbtion collectively)" "Should i just put the AG on hold and do a partial mash?"

Here is the recipe and numbers via hopville.com..

Batch size: 5.2gal
Boil size: 4.0gal
OG: 1.051
FG: 1.013
IBU: 29
ABV: 5.1%
Eff%: 65%

7# American Two-row Pale
2# Chocolate Wheat Malt
.5# Flaked Oats
.5#Flaked Wheat
.5#Black Patent Malt

.5oz East Kent @ 60
.5oz Northern Brewer @ 60
.5oz East Kent @ 10
.5oz Northern Brewer @ 10

Cheers y'all and thanks! :rockin: :tank: :rockin:
 
Although some folks with flat out say it can't be done, it screws with your efficiency, it makes crappy beer, I do top off ag batches all time. I often do 5 gallon batches dilluting 2.5 gallons of wort with 2.5 gallons of water.

And I've won awards for some of them...

I've been doing quite a lot of them in the winters in the last couple of years.

I do it a lot in the winter when I can't brew outside. I use a pre-boil gravity of 3.5 gallons boiled down to 2.5 and topped off with 2.5 gallons of water, and I've never had an issue with efficiency whatsoever, or hop utilization problems either.

I use beersmith to calculate everything then use their "dillute with water" calculator and hit my numbers all the time. A recipe calculated in a program like beersmith that takes into account for boil size will tell you how much grain you need to achieve whatever your set efficiency is. Basically you are still making a high grav wort, like your extract extract actually is, and then using the calculator dilluting it down.

The only thing I account for is hop efficiency. And I simply up my hopbill by about 18% to overcompensate for poor hop utilization. And I bet you with a better understanding of the formuals and such, you could nail the amount you need to overcompensate more precisely that I do, but 18% more seems to work for me.

I've done everything from IPA's to really light lagers this way and have had some great beers come out of it. My Wit and my Vienna Lager made this way have both placed in comps. And another one, my chocolate mole porter picked up a bronze.

I still do a lot of half sized Ag batches, because there is no extra math involved, but over the last two years I've found that the "you can only do full sized all grain batches, and can't dillute with water," isn't exactly true....it just takes a little finegaling with the maths.

I think the idea that you "can't" is just one of those common wisdom things that folks repeat because they've heard it, and never really give it much thought, or worse yet, just repeat the premise verbatum...

Funny thing is I've discussed this with brewers who own 2 different LHBS's (and have decades more experience than me) and they've been doing the same thing for years. I first thought about it, when I overboiled a 5 gallon batch on my turkey fryer by a gallon, and sat down and played with the dillution ration to top off with water, and it returned to the gravity had I not missed my post boil volume...I started to wonder what if....and it's been fun. Especially finding out that it works for many different styles, from really hoppy to not subtle brews.
 
That's pretty awesome news, I've been wondering the same thing myself...Using DeathBrewer's stovetop partial-mash method but going all the way with grain.... Might be a stress on the nylon paint strainer bags, but then again, maybe not!

Very cool.
 
beersmith beersmith beersmith. Sadly, im at work, i'll have to remember to dl it tomorrow since im working late hours tonight. *sigh* that is unless someone wants to plug my numbers in. :D

I figured you could do AG and not do full boils, its not 'proper' but its not 'wrong'... its just against the grain. (see what i did there? zing!)
 
+1 to what Revvy said. I've done it a bunch of times without any issues too.
 
Revvy stated everything I was going to. I've been doing this all winter. I have a 5 gallon pot and start with 4.5 gallons. I only have to top up with 1.5 gallons at the end. I switched to save on Propane costs mostly.

The naysayers can say what they want. Before I tried it, about 90% of the posts on the topic said it wasn't a good idea. This method makes the same quality beer as my non topped up batches did.
 
Honestly it's any typical 5 gallon recipe. Nothing really special in the grain bill. It's all in playing with the numbers in BS.

I can try to explain it off the top of my head, but forgive me if I miss a few details. Though it's not difficult.

1) Basically you create a 5 gallon recipe in beersmith.
2) Make note of the og and ibus.
3) Figure out what 18% more of your ibus are, then using the ibu's tab in beersmith let the software recalculate the hopping amount to account for it, or do it yourself.
4) Change the Batch Size to whatever you want to be able to boil on your stove. If it's 4 make it 4- I tend to do 2.5 with a 3.5 pre-boil volume-make sure you adjust BS to the pre-boil volume to reflect your boil off rate.
5) After you change your batch size your og is now going to be quite a bit higher than it was when it was a 5 gallon. Obviously- a thicker wort is going to have a higher gravity. Make a note of this higher gravity.
6 Click on the dillution ratio calculator in your software, beersmith's looks like this-

dillution_copy.jpg


7) Enter the starting Wort volume (which is your final volume from step 4 above, mine would be 2.5).
8) Enter the specific gravity of the thicker wort.
9) Click on the "dilute with" drop down and select water.
10) Enter the top off amount of water you need to get to your 5 gallons (Volume to add) and you should see that "magically" the calculated "final specific gravity" will be what it would have been if you had done a normal 5 gallon final volume boil. In other words it should match the Og you made note of in step 2.

Now what I do on brew day to take it out of the theory of recipe creation and into the practice of what really happens on brew day is that I mash and sparge into a bucket with graduated measurements so I know exactly what my preboil volume is. Then I take a refractometer reading to see what my real preboil gravity is, then I re run steps 6-10 to see what the real numbers will be.

Or I do it after I cool my wort and before I top it off with water- I just rack my cooled concentrated wort into my bucket or marked carboy to see how much I have post boil, then run steps 6-10.

Then I top off with water, aerate the wort and pitch yeast as normal.

Hope this helps. I think I remembered all the steps.

Now obviously you CAN just wing it. Just take your recipe only mash and sparge enough to get your small batch preboil volume, boil your wort and top off. Whether you actually run the numbers or not really is irrevelant the gravity of the wort is going to be exactly higher by exactly what the missing amount of water would lower to when you dillute it by the right amount. If that makes any sense to you.
 
+1 to the Rev. I actually have been trying lately to set my pre-boil volume so that at flame-out I am just barely under my desired volume. (i.e. for a 5.25 gallon batch I'll try to hit 4.75-5 gallons)

Then measure gravity, use the dilution tool in beersmith to hit desired OG and call it good. Never had an issue.

Also, consider if you're a little under volume it's a lot easier to fix than being over volume!
 
Is there a dilution tool in beersmith to work out the IBU's or just gravity?

I only need to add a small amount of water to the end result so the 18% figure would be way out for me.
 
Is there a dilution tool in beersmith to work out the IBU's or just gravity?

I only need to add a small amount of water to the end result so the 18% figure would be way out for me.

Not really. But the thing to realize if it's only a top off of a gallon or so, the difference is really not going to be that noticeable to the palate. We can't really distingush for example between 10 and 13 ibus. A gap between 10 and 25 1bus would be a different matter however.
 
Well I'm working in litres and each top off would be 1.3g. So just under 4gs post boil and topped up to 5g in total. Might only need to top up my IBU by a few points. I take it when I adjust the boil size down without changing the the scale of the recipe brewsmith takes into account the hop utilisation? IF thats all correct it shouldn't be hard.
 
Ahh got it, should of looked for the gravity into the boil in the brewhouse tab. Still with my planned dilution amount its still few pts short in the OG when diluted.
 
If it matters I do my AG batches by splitting my wort into 2 separate pots. A 4.25 gal pot and a 3.25 gal pot. I time each one separately and divide the additions between the two. It works well... since the small pot always boils first, when I'm done chilling the little one the big one is ready to come off the stove. Beers made this way taste great. I'm considering a larger pot but almost don't care if I get one. The guys at my LHBS clued me in to this little work around. I hadn't thought of trying to make super concentrated wort like you suggest and diluting it.... Maybe if I lose a pot or really want two brews going simultaneously.
 
Its not that concentrated. A Revvy says he basically does a half half mix and I'm only topping up by a quarter.

Think I have it nailed.

In the end I'll end up with

OG into boiler 1056
Post boil in the region of 1062
IBU in boil 24

After dilution of 1.3g per fermenter x2 (2.64g in total)
OG into fermenter 1046
IBU roughly 20

Perfect for my heffe.

Thats after scaling the recipe to full, putting the boil volume down to what it will be. Hop amounts change automatically it seems and at the 24 IBUS listed above.

OG of the boil jumps about 10 points in the process.

Dilution tool used with the water I want to add and it gives me an acceptable OG into fermenter.

Will give it a go and see what the end result is. Thanks guys and if any of the above is off please say so.
 
All of my beers are 4 gallon boils. No problems here. If I could boil 5 or 6 gallons I would, but I can't. But I still get good results.
 
BIAB brewers do this sometimes, in order to brew higher gravity batches than their pot size allows. Believe its referred to as maxi-BIAB. You can read more about it on the BAIBrewer website.
 
****, in theory I could make a Olympic swimming pool size batch with a tea kettle. Imagine the gravity of that concentrated wort. Somewhere between crude oil and cement.
 
I'm not sure I agree. If Revvy is making 5 gallon batches with 2.5 gallon boils, it stands to reason that doubling would have the same result... no?
 
Honestly it's any typical 5 gallon recipe. Nothing really special in the grain bill. It's all in playing with the numbers in BS.

...

Now obviously you CAN just wing it. Just take your recipe only mash and sparge enough to get your small batch preboil volume, boil your wort and top off. Whether you actually run the numbers or not really is irrevelant the gravity of the wort is going to be exactly higher by exactly what the missing amount of water would lower to when you dillute it by the right amount. If that makes any sense to you.

Resurrecting this thread because I just got my first mash tun set up (a 10 gallon Igloo), but don't have my outdoor burner yet so I am still limited to a partial boil on the stove top (~4 gallon pre-boil volume max). I plan to try out this top-off method that Revvy has mentioned.

I just need one clarification. From the above it looks like you do not adjust the grain bill up or down based on any of the calculations, just the hop bill. Am I correct in that assumption? For some reason it seems like if I am using less sparge water I would want either less or more grains to extract the same amount of sugars.
 
Resurrecting this thread because I just got my first mash tun set up (a 10 gallon Igloo), but don't have my outdoor burner yet so I am still limited to a partial boil on the stove top (~4 gallon pre-boil volume max). I plan to try out this top-off method that Revvy has mentioned.

I just need one clarification. From the above it looks like you do not adjust the grain bill up or down based on any of the calculations, just the hop bill. Am I correct in that assumption? For some reason it seems like if I am using less sparge water I would want either less or more grains to extract the same amount of sugars.

No, you are not adjusting the grains, just adjusting the hops due to the difficulty of a more viscous wort to, I don't know how to describe it, "take in" the acidity of the hops.

I don't recall where the 18% came from, I think it was a "rule of thumb" mentioned to me from a friend who owns a homebrewshop telling me that when I was talking through the "why do folks say this can't be done, when it really is the same thing as a maltser making liquid malt extract and a homebrewer doing a stovetop 2.5 gallon boil topped of with water, so I call bs on this one," discussions. And he and another owner said they'd both been doing it for years this way before they got burners for full boils.

But upping the hops 18% seems to work...
 
I've didn't know there was a dilution tool in Beersmith so I've never used it, but if you plug in the 5 gal recipe with the correct top off water and actual boil size it will tell you what the concentrated pre-boil gravity should be (one of the fields you can set to show on the recipe page). It does also adjust the IBU's when you do that - I've always just gone with those calculations. Looking at one of my recipes it looks like it's making about a 20% adjustment so in line with that Revvy noted. One thing I would say about adjusting the grainbill is you may have to adjust for changes in efficiency. When I do my regular 3 gal all grain batches I get about 77-78% efficiency. When doing a really big beer - or in this case a concentrated wort and topping off to 5 gal - I find it's more in the 70-72% range. I've not really tried to chase this much though, for example even though BIAB'ing I don't do any super fine crushes or anything. YRMV.
:mug:
 
I have figured out on my gas stove I can actually boil 5 gallons, but it is not a vigorous "rolling" boil, more like simmering one. This definitely would affect hot break but means I would only need to add a gallon or less after the boil.

I can get 3.5 to 4 gallons at a pretty good boil, so given evaporation can add 2 - 3 gallons top off to make a 5 gallon batch.

So that leads me to the decision point. If you had the choice between an almost full boil albeit a gentle one versus this top-off method with vigorous boil what option would you choose? There are obvious trade-offs either way.
 
Rdwhahb.... Try both methods...or I would suggest the larger boil partially covered.

Even a piece of aluminum foil covering a third of the kettle top will bring a mor vigorous boil.

I think I would go with the larger less intense boil, if need be boil longer and time late hops with flame out.

Doesn't make much difference with the bittering addition if boiled for 60 or 75 minutes.

The top up is also an option to assist chilling, a gallon or two of frozen spring water can help get you the last 20-30 degrees pronto. Freeze the water, then cut the jug off with a razor knife.

Either way has plus minus....cheers!
 
I have put a lid on top kick the boil up, then taken it off after a minute or two...and done it every little while..but usually if you do it once the boil kicks up and is more vigorous after.
 
Although some folks with flat out say it can't be done, it screws with your efficiency, it makes crappy beer, I do top off ag batches all time. I often do 5 gallon batches dilluting 2.5 gallons of wort with 2.5 gallons of water.

And I've won awards for some of them...

I've been doing quite a lot of them in the winters in the last couple of years.

I do it a lot in the winter when I can't brew outside. I use a pre-boil gravity of 3.5 gallons boiled down to 2.5 and topped off with 2.5 gallons of water, and I've never had an issue with efficiency whatsoever, or hop utilization problems either.

I use beersmith to calculate everything then use their "dillute with water" calculator and hit my numbers all the time. A recipe calculated in a program like beersmith that takes into account for boil size will tell you how much grain you need to achieve whatever your set efficiency is. Basically you are still making a high grav wort, like your extract extract actually is, and then using the calculator dilluting it down.

The only thing I account for is hop efficiency. And I simply up my hopbill by about 18% to overcompensate for poor hop utilization. And I bet you with a better understanding of the formuals and such, you could nail the amount you need to overcompensate more precisely that I do, but 18% more seems to work for me.

I've done everything from IPA's to really light lagers this way and have had some great beers come out of it. My Wit and my Vienna Lager made this way have both placed in comps. And another one, my chocolate mole porter picked up a bronze.

I still do a lot of half sized Ag batches, because there is no extra math involved, but over the last two years I've found that the "you can only do full sized all grain batches, and can't dillute with water," isn't exactly true....it just takes a little finegaling with the maths.

I think the idea that you "can't" is just one of those common wisdom things that folks repeat because they've heard it, and never really give it much thought, or worse yet, just repeat the premise verbatum...

Funny thing is I've discussed this with brewers who own 2 different LHBS's (and have decades more experience than me) and they've been doing the same thing for years. I first thought about it, when I overboiled a 5 gallon batch on my turkey fryer by a gallon, and sat down and played with the dillution ration to top off with water, and it returned to the gravity had I not missed my post boil volume...I started to wonder what if....and it's been fun. Especially finding out that it works for many different styles, from really hoppy to not subtle brews.

do you have to up your grain bill any or just your hop bill?
 
Yes you typically will need more grain as efficiency will be lower when brewing a concentrated wort and topping off. With a little math, you can measure your post boil gravity and top up to make your intended gravity rather than topping up blindly. You may not get 5 gallons but hopefully close.

If you don't up your grain bill, I'd guess you'll yield 4-4 1/2 gallons. Not bad :)
 
do you have to up your grain bill any or just your hop bill?

Only the hop bill. I've never come into a situation of doing this where I've changed the grain bill to accomodate any of the "efficiency issues" that people "swear" (usually those who have never tried it) that will occur.

Now having said that I build my recipes with beersmith, with a set efficiency in the software settings based on my system... so POSSIBLY the software is calculating that for me, but like I said I've never seen changes that warranted it.

I mean, that if I grab any other recipe of mine, and brew it, I'm STILL hitting all the requisite numbers in terms of gravity.

So in my opinion, any of these supposed issues of changing the grain bill may be so miniscule that I've NEVER had any issues, or had to use more grain to make a beer this way.

YMMV though *Shrug*

(And with all respect to my brother brewer Wilser, who where this is concerned, is prolly the only time we've disagreed on something.) :mug:
 
Thanks Revvy,
Please notice I used the word "typically" and I consider your brewing skill far superior to typical :)

I would expect a higher gravity with a 5 gallon mash and sparge compared to a 2.5 gallon mash and sparge with a 2,5 gallon water top up, with the same recipe....

If you hit your intended result or close that's all that really matters. Cheers buddy
 
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