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General Category => Going Pro => Topic started by: phillamb168 on November 14, 2011, 10:30:30 AM

Title: Scaling recipes
Post by: phillamb168 on November 14, 2011, 10:30:30 AM
Any guidelines on scaling homebrew recipes up to several barrels? Is it a linear scale or does something weird happen to the chemistry beyond X gallons?
Title: Re: Scaling recipes
Post by: a10t2 on November 14, 2011, 03:40:55 PM
There aren't any chemical effects IME. You just need to make adjustments to fit the equipment, like changing to any other brew system, regardless of scale. Your boil-off will probably be proportionally less, for example.
Title: Re: Scaling recipes
Post by: Gribble on November 15, 2011, 12:09:14 AM
Also in an example of scaling up, there are some things that will require less of, spices for example, what was fine at 10 gallons may be too much in a 3 bbl system.
Title: Re: Scaling recipes
Post by: tschmidlin on November 15, 2011, 12:20:26 AM
Keep in mind that chilling may take a lot longer, so anything you add late (like spices as mentioned, or late hops) will be in the hot liquid for that much longer than on some homebrew setups. 
Title: Re: Scaling recipes
Post by: narvin on November 15, 2011, 01:02:53 AM
I've heard that you get more extraction from hops in big batches, but I have no experience to say if this is true or not.

From ProMash help:

Kettle Size Hop Utilization Scale Factor

When scaling a home brew size recipe to micro-brew size, the micro-brewer may need to set a value here to reflect the increased hop utilization common to large batches and professional kettle geometry. Entering a value above 1.000 will result in higher IBU predictions in the stand-alone IBU Calculator as well as the IBU calculators imbedded in the  "recipe" and "brewing sessions" formulation screens.  Entering a value that is less than 1.000 will result in the converse being true.

As an example, the author has found that a value of 3.4 is appropriate in his brewery when scaling a 10 gallon recipe to  a batch of 17 barrels. However, this may be completely different on your system, and we urge you experiment with a known recipe and "tweak" this number until the IBU values reflect accurate, known values.

Additionally, if you are trying to compare the IBU values generated in ProMash to another IBU calculator, keep in mind that very few (if any) take the "Kettle Size" factor into account,  and the numbers will never match if the "Kettle Size Factor" is set to anything other than 1.0. The reason for the "Kettle Size Factor" is that most of the IBU formulas (with the exception of Tinseth) are curve fits and were based on small batches that home brewers use (Rager's formula is the perfect example of this), and really big, well designed kettles can simply utilize hop acids far beyond what is possible with small scale kettles.
Title: Re: Scaling recipes
Post by: EHall on November 15, 2011, 02:38:31 AM
I usually do 5gal batches but a few years ago I built a 1gal system to do test batches on. I can tell you that linear scaling doesn't always work. 1/5# of victory tastes different in a 1gal batch than 1# of it does in 5gal batch. There's other specialty grains that I have run into this with too. All I can tell you is think it through a bit when you're scaling as to what grains/hops/spices you're using and maybe dial it down a notch...
Title: Re: Scaling recipes
Post by: Gribble on November 15, 2011, 07:10:28 AM
Your base grain will usually stay about the same, but your specialties, especially some of the bolder flavors (black malt, aromatic, special B), will usually get scaled back a bit.
Title: Re: Scaling recipes
Post by: phillamb168 on November 15, 2011, 09:50:19 AM
Your base grain will usually stay about the same, but your specialties, especially some of the bolder flavors (black malt, aromatic, special B), will usually get scaled back a bit.

Are there any books/PDFs/etc on best practices for this? I haven't checked my copy of Designing Great Beers but perhaps there's something in there?
Title: Re: Scaling recipes
Post by: tygo on November 15, 2011, 11:38:32 AM
I haven't listened to this one yet but it looks like Jamil Z has recently covered this topic:  http://thebrewingnetwork.com/shows/808