2.5 gallon batches

Hi all,

In a previous thread, I was discussing storage space as a major issue for me. I just don't have the space to brew many 5 gallon batches and store all the resulting cases of beer. Also, I just dont drink that much beer that quickly... anymore.

So, as a compromise for both space and to some degree, cost -- I'm thinking of doing 2.5 gal batches. That way, I can experiment to my hearts content (that is what a hobby is for, right?) without generating huge quantities of beer that I may or may not like. If I do make something that I really like, then I will go back and brew a full 5 gallon batch.

There have been several threads on brewing 2.5 gallon batches:
https://www.homebrewtalk.com/f39/2-5-gallon-batches-81047/
https://www.homebrewtalk.com/f36/ag-brewing-2-5-gallon-batches-147585/

But I couldnt find a concrete answer as to whether to make a 2.5 gallon (extract or PM) full-boil batch, would I just half the recipe from a 5 gallon recipe, or is it more complicated than that.

I'm not sure how switching from a partial-boil 5 gal to a full-boil 2.5 gal would effect things. Nor am I savvy enough to know whether simply halving recipe is okay for the hops and their utilization.

Could somebody share their experience on this, or point me to a thread I may have missed with my search query.

Thanks.

In general, yes you can just half the recipe. Since you are going from part-boil to full there is theoretically a hops utilization change, but there are websites where you can play around with the ingredients, boil volumes and hops additions to adjust for this.

http://www.beercalculus.com

Yes, if your stove can handle a full volume boil, then you do it full size. Generally speaking, you start with a pre-boil volume of 3-3.5 gallons to whoch you boil down in the course of an hour to an hour and a half down to the final volume of 2.5 gallons.

If your stove can't handle that, then you would figure out how much you can boil, and top off to your final volume, it doesn't really matter.

Here's some info I have put together before.

I use my normal 5 gallon mash tun for most of them, but I do a lot of Experiments, test recipes, or beers that I know I won't need/want more than a case of.

I sometimes use an unmodified 2 gallon cooler for a lot of my small btaches it holds up to 4 pounds of grain.

I just us a folding steamer in the bottom along with a grain bag. Just break off or unscrew the center post.



One of these, it helps to lift the grain bag above the spigot to keep the drainig from getting stuck.







I posted a lot of info in the mr beer thread that you may find helpful.

I posted some all grain small batchrecipes here, https://www.homebrewtalk.com/785533-post702.html

ANd a bit of a primer on AG with pics here https://www.homebrewtalk.com/738927-post659.html

But I mostly use my regular 5 gallon cooler mash tun which holds 14 pounds of grains...and 14 pounds of grain for a 2.5 gallon batch can be a mighty big beer.....


One of our memebers chubbykid had plans for a minikeg mashtun http://sites.google.com/site/chubbykidhomebrew/Home/equipment/mini-keg-lauter-tun



THe basic brewing radio guys are big fans of tiny batch brewing...3/4 gallon (1 6pack) in a 1 gallon winejug fermenter.

They demo the 6-pack IPA here

[ame]http://en.sevenload.com/shows/Basic-Brewing/episodes/PERGFAJ-01-12-06-Basic-Brewing-Video-A-Six-Pack-of-IPA[/ame]

and they also have done barleywines as well.

I ferment my 2.5 gallon batches in all manner of things, I have a 3 gallon better bottle, I also use 3 gallon water jugs, AND my old Mr Beer keg (it's perfect because you can even lager in your own fridge with it when you are starting out.)

You can even ferment a 2.5 gallon batch in a 5 gallon carboy if you want, though I would say a 6.5 gallon carboy is a little too much headspace for my confort.

Hope this helps....any more questions feel free to ask...

JJL said:

In general, yes you can just half the recipe. Since you are going from part-boil to full there is theoretically a hops utilization change, but there are websites where you can play around with the ingredients, boil volumes and hops additions to adjust for this.

http://www.beercalculus.com

Click to expand...

I've found the need to correct for hop utilization issues actually to be quite negligable, and just cut the hops in half as well. I have found that a digital sclae, that can measure in grams is quite helpful for that.

Revvy said:

I've found the need to correct for hop utilization issues actually to be quite negligable, and just cut the hops in half as well. I have found that a digital sclae, that can measure in grams is quite helpful for that.

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Agreed. In theory, hops utilization changes, but in practice, it's mostly irrelevant. Let's face it, we're talking about 2.5 gals of beer and fractions of an ounce of hops. That addition or subtraction of 1/10th of an ounce of hops to equivalize the IBU's is almost undetectable in the finished product.

JJL said:

Agreed. In theory, hops utilization changes, but in practice, it's mostly irrelevant. Let's face it, we're talking about 2.5 gals of beer and fractions of an ounce of hops. That addition or subtraction of 1/10th of an ounce of hops to equivalize the IBU's is almost undetectable in the finished product.

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Eaxactly!!!! It often comes down to 1 single hop pellet when you calculate it out. Not really worth the agrovation to calculate.

Revvy said:

Yes, if your stove can handle a full volume boil, then you do it full size. Generally speaking, you start with a pre-boil volume of 3-3.5 gallons to whoch you boil down in the course of an hour to an hour and a half down to the final volume of 2.5 gallons.

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Hey Revvy, thanks for the insightful response. Right now, its just extract (and occassionally PM), so two questions for a full boil:

1) would a 5 gallon kettle be big enough to avoid boil-over?
2) do you do a "dummy" run on your kettle to see if 3 or 3.5 gallons of water is needed to boil down to 2.5 in an hour (boiling efficiency/water loss), or just pick one and go for it?

What happens if you boil 3.5gallons down and you have a final volume > 2.5 gallons? Boil longer to reach 2.5 gallons and chill, or chill it all and only transfer the 2.5 gallons?

Boil over is an issue regardless of the size of the kettle. It can happen even in a converted keg. I use Fermcap-s in all my boils. Even on the stove top in my 5 gallon kettle which doesn't really hold 5 gallons. It's 5 gallons if filled to the brim. But with 2-3 drops per gallon, I can fill it up to about 1.5 inces from the brim, get a roiling boil on my stove and take a nap between hop additions.

I did a dummy run with water to calculate boiloff in an hour-hour and a half

I boil down, and rarely is it over the 2.5 gallons. If it's over It's not by much, and I enjoy the fact that I'll have extra beer. If it's too short I'll top it off to 2.5 gallons.

Thanks for the clarification. So, if I'm going to quote you correctly,

1) you dont see a need to adjust my hops to account for differing utilization going from a partial-boil to a full-boil?
2) all the ingredients can be adjusted linearly for the boil size.

Full boil. I scale down the ingredients but use BeerSmith to make sure that everything falls into place correctly. I try to be as specific with the recipe as I can so I can recreate it later.

You guys cut the hops in half?? Here's the data I have on one of my recipes:
5 gallons - 1.50oz - 16.3 IBU (Standard recipe)
2.5 gallons 1.50oz - 18.3 IBU (Everything halved except hops)
2.5 gallons 0.75oz - 9.1 IBU ...which technically makes the recipe too low for the BJCP guidelines...

2.5 gallons 1.35oz - 16.4 IBU (fractions but it brings it back to the original recipe)

I'm not trying to start a war or anything, just some things to consider.

I've always just gut my recipe in half, or quarter or doubled them, hops and all. Never had any issues. I've done everything from light lagers to hop bombs this way, and even picked up some medals for some of these beers.

After listeninning to Palmer basically change his opinion about IBU's from the first edition on this old basic brewing, I come to realize that quibbling with the numbers in terms of hops is really a waste of time anyway.

March 20, 2008 - What Is an IBU . . . Really?
John Palmer, author of How to Brew, shares information from a conference that challenged his concept of what defines an International Bitterness Unit (IBU).

Click to listen, Mp-3

Click to expand...

We really can't distinguish the difference between 16.3 Ibus and 18.3 by taste anyway. It's not like a beer that is supposed to have 8 ibus suddenly turns out to have 40 when cut down to a 2.5 gallon batch.

Teromous said:

Full boil. I scale down the ingredients but use BeerSmith to make sure that everything falls into place correctly. I try to be as specific with the recipe as I can so I can recreate it later.

You guys cut the hops in half?? Here's the data I have on one of my recipes:
5 gallons - 1.50oz - 16.3 IBU (Standard recipe)
2.5 gallons 1.50oz - 18.3 IBU (Everything halved except hops)
2.5 gallons 0.75oz - 9.1 IBU ...which technically makes the recipe too low for the BJCP guidelines...

2.5 gallons 1.35oz - 16.4 IBU (fractions but it brings it back to the original recipe)

I'm not trying to start a war or anything, just some things to consider.

Click to expand...

Really what we're talking about is the theoretical vs. practical differences in hops utilization. I'll assume that your BS calcs are accurate, and the IBU's go from 16 to 9. This would make the 2 beers theoretically different in terms of bitterness. However, given all of the other components that make up the flavor of a beer, the likelihood that you would taste a significant difference in the bitterness of the 2 beers is small. Also, you have to consider that a lot of the calculations that are done by and for homebrewers are a little hazy when it comes to the science behind them. Many are based on averages and generalizations - e.g. 3/4 cup sugar for priming, the formula for calculating wort for krausening, HBU's for equivalizing bitterness across hops varieties. Not sure how BS calculates IBU's, but I wouldn't be surprised if it is a somewhat generalized equation. I usually look at IBU's in terms of ranges as opposed to hard numbers.

Revvy said:

We really can't distinguish the difference between 16.3 Ibus and 18.3 by taste anyway.

Click to expand...

Right, that's what I'm saying though. In this instance it's better not to halve the hops. If a person is sensitive enough to notice a difference in IBU's, it's going to be a difference of 7 (halved) rather than 2 (left as is).

@JJL: I agree that many of the measurements we use are generalizations and averages, but these are the generalizations we all base our measurements on. Look at the US measurement of a 12 inch foot. It's very arbitrary but it's what many people still use, because it's accepted. That is a good point looking at them in terms of ranges though. Another thing to consider is the brewing process. These numbers are based on ideal conditions, and don't account for the mistakes we make as brewers. Just more food for thought.

I'll throw this little tidbit out there just to round out the discussion. Also because I so rarely get to use anything I learned in college in beer discussions. There is a principle of perception called Weber's Law. It basically says that there has to be a specific amount of change in a stimulus for a person to recognize a difference in the stimulus. (It's called Just Noticeable Difference for those who might care to know.) For taste, this threshold is 20%. So, for you to perceive a difference in bitterness when you taste a beer, there must be a minimum of a 20% change in the actual bitterness of the beer. Otherwise, the beers will be perceived as equally bitter.

20% missing from 100 IBUs is going to be much more noticeable than 20% from 10.

Teromous: spot on.
I know this post is long dead but I recently found it while google-searching on the topic of 2.5 to 5 gallons.
Naturally no one's wrong in this topic, but for those of us who are very detail oriented about rebrewing old recipes and sharing recipes with friends, it makes a big difference.

Some brewers like to claim that IBUs are overrated and the math is all relative but I've found time and again that if you are consistent and well documented with your own brewing, you'll know that's not the case.

Cheers!

Old thread but does anyone brew 2.5 gal batches in a small condo? I just brewed 1.5 gal batch of Cottage House Saison and I was thinking that it's just too much work for 1 gal when the recipe gets to be more complex.

What I want to know is what equipment you're using, especially if you're using some type of gas burner. Our place has a glass top stove that can barely keep 1.5 gallons at a boil so I need something that'll get hot enough but also not take up tons of space. I have hardly any storage space and it's too cold to brew outside. I'm thinking some sort of camping stove burner? I do not have space for 5 gal equipment nor am I able to store and drink that much beer. Thoughts?

jpoppinmoneyunit said:

Old thread but does anyone brew 2.5 gal batches in a small condo? I just brewed 1.5 gal batch of Cottage House Saison and I was thinking that it's just too much work for 1 gal when the recipe gets to be more complex.

What I want to know is what equipment you're using, especially if you're using some type of gas burner. Our place has a glass top stove that can barely keep 1.5 gallons at a boil so I need something that'll get hot enough but also not take up tons of space. I have hardly any storage space and it's too cold to brew outside. I'm thinking some sort of camping stove burner? I do not have space for 5 gal equipment nor am I able to store and drink that much beer. Thoughts?

Click to expand...

You might want to consider an induction cooker. You'll have to have plenty of ventilation using a camp stove which could be a pain in the middle of winter.

What about a heat stick to augment the stove? I want to say Brewers Hardware sells them??

hmm. I'm not sure a heat stick would be enough. I can barely boil 1.5 gallons with the lid cracked :/ .

Induction is a good idea though. I know they make single burner ones but i'm not sure how much they are.

jpoppinmoneyunit said:

hmm. I'm not sure a heat stick would be enough. I can barely boil 1.5 gallons with the lid cracked :/ .

Induction is a good idea though. I know they make single burner ones but i'm not sure how much they are.

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I saw one at Walmart recently for $70.

Induction only works on magnetic pots though. Try sticking a magnet to the bottom of your pot so you know if you need a new one or not. If you are shopping for a pot, take a magnet with you.

jpoppinmoneyunit said:

hmm. I'm not sure a heat stick would be enough. I can barely boil 1.5 gallons with the lid cracked :/ .

Induction is a good idea though. I know they make single burner ones but i'm not sure how much they are.

Click to expand...

Are you using the stick alone, or with the stick and stove?

If you own the condo, use this as an excuse to upgrade your range/stove.

Otherwise, speak with your landlord and ask him what the deal is.

Or... Induction. Same argument as above: drop in a line.

I do 6 gallon batches on my gas stove... Just barely able get to a boil with the kettle over 2 burners... Adding a cheap-ass heat stick from Amazon (https://www.amazon.com/dp/B00PFZFK78/?tag=skimlinks_replacement-20 ) in addition to the stove gets me to a vigorous boil...

I'd bet it would work for you.

jtratcliff said:

I do 6 gallon batches on my gas stove... Just barely able get to a boil with the kettle over 2 burners... Adding a cheap-ass heat stick from Amazon (https://www.amazon.com/dp/B00PFZFK78/?tag=skimlinks_replacement-20 ) in addition to the stove gets me to a vigorous boil...

I'd bet it would work for you.

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That heat stick works for you? Just plug right into the GFI on the countertop?

Chesterbelloc said:

That heat stick works for you? Just plug right into the GFI on the countertop?

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Yup...

Works a treat!

I couldn't boil with the stick alone (only 1000W) but as a supplement to my stove, I get to mash temps quicker and from there to a boil faster, too. Plus a very vigorous boil. I sometimes turn off the stick until the boil-off lowers the level in the kettle, to prevent splashing.

It is aluminum, so you have to be OK with that vs stainless. I use an Al kettle, so not a problem for me. You just have to remember to boil (and discard) some water first to build the passive oxide layer on the element. Then all is good!

If I were to buy a stainless one, I'd probably go with the from @Bobby_M ... That sucker looks nice!