How to double an All Grain Recipe?

[davepeds]

I swear I tried a ton of different search words to figure this out - but haven't.

Many, or most, of the recipes in the database are for 6 gallon batches. Well, if I spend the time to mash and boil, I'd rather use the full capacity of my keggle to make a 10 gallon batch. Then, split it into two carboys and cope with slightly different beers that my little yeasties make - as mentioned in many previous posts.

However, does one simply double the 6 gallon recipes? What do you do about the hops? Double those, too? I feel like there has to be some tricky-ass science to this, and. I.. has... confused..!?

 

[passedpawn]

Just * 2

No tricks

 

[dbreienrk1]

Do you have a calculator? Just cross multiply. C*B/A=D

A = original batch size volume (6 gal)
B = grain in lbs for original volume (x lbs)
C = new batch size (10 lbs)
D = calculated grain weight

Just do it for each type of grain and hop. Or calculate the percentage of grain bill for each grain and do the total weight. Then apply the percentage to the total weight...clear as mud?

 

[two_one_seven]

just * 2

no tricks

*2......

 

[dbreienrk1]

Just * 2

No tricks

Well, it's not quite as simple as *2 because 6*2 doesn't equal 10...

 

[two_one_seven]

Well, it's not quite as simple as *2 because 6*2 doesn't equal 10...

Agreed.....lol. Although most recipes are for 5 gal batches. Perhaps the OP has confused starting volume with post boil volume?

 

[TyTanium]

Agreed.....lol. Although most recipes are for 5 gal batches. Perhaps the OP has confused starting volume with post boil volume?

I think the OP was responding to the thread title "How to double a recipe"

The important thing is that recipes are scalable.

 

[davepeds]

OK - I think I can follow that. Not too tricky. However, are the hops just doubled, no tricks? Same for bitter, flavoring, and finishing hops?

 

[Yooper]

OK - I think I can follow that. Not too tricky. However, are the hops just doubled, no tricks? Same for bitter, flavoring, and finishing hops?

Yes. The hops utilization will change a bit, but not significantly so you just x2 everything.

 

[davepeds]

Thanks, Yooper. And where do you winter in Texas? Are you of the Harlingen ilk? Or keeping it classy in Corpus? Is somebody smuggling brew supplies across from El Otro Lado?

 

[Yooper]

Thanks, Yooper. And where do you winter in Texas? Are you of the Harlingen ilk? Or keeping it classy in Corpus? Is somebody smuggling brew supplies across from El Otro Lado?

I'm north of Corpus, on the coast (Rockport area). No brew supplies, but I did bring three kegs with me and have a kegerator in our kitchen so I'm not too hard up!

 

[beerman0001]

Just remember you are going to boil off the same amount of liquid for the double batch as you would for the single. So if I was doing a 5 gal batch I start with 6.5 gal. If I am doing a 10 gal batch I start with 11.5 gal.

 

[davepeds]

Do you have a calculator? Just cross multiply. C*B/A=D

A = original batch size volume (6 gal)
B = grain in lbs for original volume (x lbs)
C = new batch size (10 lbs)
D = calculated grain weight

but, wait? Is that "C" supposed to new batch size (gallons)? Because (10 lbs) doesn't make a lot of sense to me. of course, it doesn't change anything - just for clarity.

is it.... 10gal * lbs of original grain bill / original vol = weight of new grain bill

 

[davepeds]

Do you have a calculator? Just cross multiply. C*B/A=D

A = original batch size volume (6 gal)
B = grain in lbs for original volume (x lbs)
C = new batch size (10 lbs) <---typo, should be "gal"
D = calculated grain weight

Just do it for each type of grain and hop. Or calculate the percentage of grain bill for each grain and do the total weight. Then apply the percentage to the total weight...clear as mud?

Correction
If you have a 5 gal batch that calls for 10 lbs, the corresponding 10 gal batch would have 20. If you have a 3 gal batch that calls for 6.75 lbs, the corresponding 10 gal batch would be 22.5.