General Recipe Clarification

[Bottoms_Up]

Many recipes usually provide the ingredients and directions for a specified volume, usually 5 US Gallons or 19 liters. However, when you brew it, you generally aim for, let's say, 5.25 - 5.5 gallons (after boil), to account for the trub that you must remove before fermentation.

My question is: do you proportionately increase the ingredients in the recipe to match the larger 5.25-5.5 gallon volume, so that the remaining 5 gallons will be true to recipe, or has the recipe generally already accounted for the additional 0.25-.5 gallons?

Thank you.

 

[Hammy71]

Most recipes (unless stated) are for 5 gallons going into the fermenter. So, if your want 5.25 going into the fermenter or you want to leave .25 in your kettle, you'll have to up the recipe to accommodate that. You do have to be careful though, Jamil's recipes from Brewing Classic Styles are 6 gallon recipes. He does this to accommodate for what I mentioned above.

 

[mvcorliss]

My understanding is that Classic Style recipes are 5.5 gal. recipes. On page 35 of my copy it says 6 gal at the end of the boil and 5.5 gal into the fermenter.
That said, to the OP, yes, you must scale up or down to match whatever volume the recipe is for. Also, you want to check the efficiency the recipe is written for and adjust to your efficiency.

 

[Bottoms_Up]

Thanks for the replies! You're right, I forgot about checking Jamil's book - I just checked pages 34-35 of "Brewing Classic Styles" and it states: "However, the ingredient quantities and hopping schedules are still based on a 7 gallon boil (26.5L), with 6 gallons (23L) at the end of the boil, 5.5 gallons (21L) going into the fermenter, and 5 gallons (19 L) going into the bottles or keg."

So I therefore assume that most recipes likely do account for the 2 gallon loss through boiling and trub matter. That explains why my specific gravity always seems a little too high (in the past, I adjusted recipes upwards to account for the loss).

 

[Hammy71]

Boiling yes, trub no. They are based on what you have in the kettle after boiling is complete. So, your starting volume pre boil, has nothing to do with the recipe scale. The amount you want at the end of the boil does.

 

[Bottoms_Up]

Hello Hammy71,

Thanks. Perhaps that does apply to most of the recipes, but it seems clear in Jamil's book that his ingredients do not have to be adjusted to account for the additional volume at the end of the boil. He has already adjusted the ingredients so that, by the time you are down to 5 gallons after fermentation and filling the keg (or bottles), the gravity, IBU's, etc. are just right. So perhaps his recipes differ from recipes posted elsewhere in terms of adjusting for the extra volume at the end of the boil.

 

[Yooper]

So perhaps his recipes differ from recipes posted elsewhere in terms of adjusting for the extra volume at the end of the boil.

Yes, he's the only one I know that does that. Most "5 gallon recipes" have 5 gallons at the end of the boil, and what you put in the fermenter is up to you. If you want to have 5.5 gallons at the end, so you can leave .5 gallon behind in the boil kettle, the recipes should be scaled up.

 

[SpeedYellow]

There's really no answer to this, and it's academic anyway. All you can do is run the numbers on the recipe and see if, given your typical efficiency, you can hit their OG and volume. If not, then just make 4.x gallons or use more grains. (Of course I'm talking all-grain here). We all get different brew house efficiencies, so I'd never expect to be able to use someone else's recipe without adjusting for my system.

 

[Bottoms_Up]

Thanks, Yooper and SpeedYellow. Knowing that there's no consistency to the approach to providing recipes is very helpful. I wasn't sure whether or not they were standardized. You are right to suggest that the numbers should be run to see if it then hits the right OG and volume, given the estimated efficiency of one's system.