Bugeater wrote:SouthernBrewlady wrote:Hate to sound like a dummy, BUT: I've never converted a recipie just from percentages. Usually I have pounds or grams or liters or something. Do I just plug it into beer smith?
I don't think you can just plug in percentages, but then I just use Promash. The way I do it is fairly simple. For a beer of that gravity, you will have a total grain bill of about 10 pounds. Enter each of your grains into your recipe program. For the amount just enter the the amount corresponding to the percentage of 10 pounds. For example, this recipe calls for 84% base malt. That works out to 8.4 pounds. Breaking that down further, 20% of that is Maris Otter. 8.4 X 20% = 1.68 pounds of Maris Otter.
Go on and do this for the rest of the ingredients. When done, take a look at the projected gravity. It will probably be off a bit (maybe quite a bit).
Another method to use is one I do, and I do it specifically because Beer Tools Pro doesn't have the capability (any developers reading here? hint hint). I've got a simple excel spreadsheet set up that I can use to find out exactly what quantity I need for a given grain and if you want to use it you need the following:
- Your
batch size (gallons).
- Your
desired gravity in GU (ex: 1.053 = 53).
- The
percentage of the recipe this grain will cover.
- The grain's original
gravity potential (in BTP it's the "Original Grav. (lb/gal)" found in the grain editor panel).
- And lastly you need to specify your
System Efficiency %.
With all of those parameters just do the following calculation:
Needed Grain Quantity (lbs) =
(((
Batch Size *
Total Gravity *
Grain Percentage) /
Grain Potential Gravity) /
System Efficiency %)
You could also do this with a calculator, but using a spreadsheet makes it dead simple. The nice thing about this method is that even if the potential yield of any given grain I buy changes between purchases it can be accounted for without having to "fiddle with the dials".
Just my 2 cents...
Edit: Formula updated to account for efficiency.
