[piratebrewer]

I have a recipe for a 5-gallon recipe and I'm planning to make a 10-gallon batch.  I've heard recipes do not scale linearly but since I'm only going from 5 to 10 gallons is this close to do a linear scale?  If not, any tips for the grains or hops?  The fermentation will remain constant because I'll use two separate carboys as I always have used in the past.

[denny]

I scale all my grains linearly.  I know there are those who only scale the base malt, but I want to retain the proportions that the original had.  One thing to take into account is that your efficiency _may_ be lower for a larger batch.  OTOH, it may not....

[tschmidlin]

Like Denny, I just double the grains when I do 10 instead of 5 gallons.  If your gravity is low in the kettle, you can always add a little DME to make up the difference.

[chezteth]

I agree with the others.  When I do a 10 gallon batch I simply double the ingredients.

Happy Brewing,
Brandon

[vista]

I have gotten into the habit of looking at recipes in percentages myself.

[tom]

2 things change with batch size. Hops bittering utilization increases with size, but not until you are up to pro size. 5 to 10 gallons is no problem.

The other is that your boil-off will be about the same volume, not % if using the same kettle and burner.  So if you are used to boiling a 1.080 up to 1.100, with a 10 gallon batch you will only get to 1.090 unless you double the boil time.

[piratebrewer]

Great tips!  Thanks for the feedback and advice.  I had not thought of the boil off difference and that makes sense; I'm sure I would have gone with percentage rather than volume.

[micsager]

Great tips!  Thanks for the feedback and advice.  I had not thought of the boil off difference and that makes sense; I'm sure I would have gone with percentage rather than volume.

I only brew ten gallon batches, and as most recipes are written for five, I simply double everything.  However, The local brew-pub did like one of my recipes, and to scale it up to the four bbl ssytem did take some tweaking.  Considering efficiency differences and such.  Beersmith made fairly easy though.  change the % efficiency, then start tweaking grains and hops to get back to your iriginal IBU, and OG targets. 

He went through the eight kegs pretty quick.

I'm gonna have my black IPA on tap there this fall. 

[denny]

Great tips!  Thanks for the feedback and advice.  I had not thought of the boil off difference and that makes sense; I'm sure I would have gone with percentage rather than volume.

AFAIAC, you should ALWAYS look at boiloff as gal./hr., not %.  Even though Promash defaults to %, Jeff Donovan advises you to change it to gal./hr.  Beersmith only does %.  Until that gets changed, I consider it a limitation that makes it difficult for me to use Beersmith.

[tygo]

Beersmith only does %.  Until that gets changed, I consider it a limitation that makes it difficult for me to use Beersmith.

I just plug the % so it reflects the right gallons per hour.  Granted it's a slight pain but I generally only do one batch size so once it's set up I don't have to mess with it for awhile.

[denny]

Good idea....I'll play around with that.  But I hope they'll change it, anyway!

[wingnut]

Your recipe will not scale perfectly linear, however, if you know a few data points, you can make the correct changes to keep the recipe tasting the same.

• Know your final gravity and make sure that your yeast will hit the same terminal gravity.
• Know your IBUs and using the brewing software, adjust your additions to keep the same IBUs
• Keep your hop additions after 30 minutes to the correct ratio (scale those up or down based on recipe size) and make any bitterness corrections to your 60 minute addition.  That way you keep the "hop flavor" correct and can account for any increase/decrease in efficiency
• Know your different kettles evaporation rate, and different mash tun efficiency rates.  Calculate your grains accordingly (I usually keep the same ratio and just bump up or down the grain bill to compensate for efficiency.  Keep in mind the goal is the same final gravity, but if you are splitting the 10 gal batch into fermentation vessles simlar to what you use for 5 gallons and pitch the correct yeast strain/qty... the OG should work too)

So while for the most part you can go linearly in your recipe, just check these few items to be sure you do not need to "fudge" the recipe a bit to account for non-linnear conditions, usually associated with changing equipment or boil size.  


In the end, even if you do not consider these few items, the beer will turn out great! So as with most things in homebrew, you can sweat as many or as few of the details as you like!

[bluesman]

I scale my recipes in an effort to achieve the same end product.  By that I mean the same OG,  FG,  IBU's,  ABV,  color ,  etc...

For the grain bill I adjust the weight while keeping the same percentages.  Hops are scaled by keeping the IBU's the same.  Yeast is adjusted by unit volume and OG as per mrmalty.

Water is adjusted in accordance with the final volume desired. 

Starting volume = final volume + grain absorption + evaporation (boil-off)

[Hokerer]

I scale my recipes in an effort to achieve the same end product.  By that I mean the same OG,  FG,  IBU's,  ABV,  color ,  etc...

Boy, did I read that wrong at first glance.  I took it that you scale all your recipes (ie. APA, Stout, Pils, etc.) so that they all end up with the same OG, FG, etc.   

[micsager]

I scale my recipes in an effort to achieve the same end product.  By that I mean the same OG,  FG,  IBU's,  ABV,  color ,  etc...

For the grain bill I adjust the weight while keeping the same percentages.  Hops are scaled by keeping the IBU's the same.  Yeast is adjusted by unit volume and OG as per mrmalty.

Water is adjusted in accordance with the final volume desired. 

Starting volume = final volume + grain absorption + evaporation (boil-off)

Thanks dude.  You explained what I was trying to say much better than I did.