The infamous "6 Gallon Batch"

[scoundrel]

Hi all I need a little help. I use Beersmith 2 and tried adding one of Jamil's all-grain recipes. Now Jamil always says he makes 6 gallon batches. If I add his recipe to Beersmith and set the batch size to 6 gallon, it syncs up fine. Now here's the problem. According to Beersmith, a "batch" is the amount of the beer added to the fermenter where my understanding is that Jamil's batch is the post boil volume. Now, if you leave the break material behind, in Jamil's scenario, you will end up with less than 6 gallons in the fermenter. So how much does Jamil add to the fermenter? I swear I heard it in one of the podcasts but I can't remember which one. Any help is appreciated!

[Elbone]

5.5 gal.

[ScootsieDoubleday]

5.5 gal.

+1 to Elbone. But let me say to the OP, it took me a while to wrap my head around it too. 5.5 is the batch size in my software.

[spiderwrangler]

Jamil's batch size --> 6 gallon post boil, leave 0.5gal of gunk behind ---> 5.5 to fermentor, leave 0.5 gal of gunk behind (post fermentation) ---> 5 gallons to the keg.

[scoundrel]

Ok perfect! That's what I thought. My batch sizes in Beersmith are 5.5. It kinda sucks since scaling down from 6 many times creates odd ingredient measurements, but oh well. It doesn't really matter as long as I'm in line with everyone else. Thanks!

[vorlauf]

if your batch size is set to 5.5 in beersmith it shouldnt require much change from the recipe's in the jamil show because the beersmith software refers to volume in the fermentor and the jamil show refers to the final boil volume at fermentation temperature which are pretty much the same for most people. my equipment in beersmith has the final boil volume at 6.4 gal minus 0.4 gal volume loss to cooling shrinkage (default value in beersmith) minus 0.5 gal loss to trub from the brew pot and 5.5 gal. into the fermentor.

[Tygo]

I plan my batch size in beersmith for 6 gallons. In the equipment settings I ignore the amounts left behind in the boil kettle (set to zero). I'm targeting 6 gallons in the kettle after the boil & the chill and I don't concern myself (in the calculations) with how much actually makes it into the fermenter.

I just tested it out in the software and if you account for losses in the kettle due to trub it impacts the OG calculation. And that's not correct IMO.

Think about it this way: You could plan for and achieve a batch size of six gallons post chill. Then transfer 3 gallons to the fermenter and dump out the remaining amount on the ground in homage to the beer gods. The three gallons in the fermenter is going to have the same characteristics (OG, IBU, etc) as the amount on the ground.

[spiderwrangler]

If I'm understanding what you said correctly, when you adjust equipment parameters such as amount lost to trub, it will adjust the initial volume to still give you the same volume out.

In that case it isn't saying that the gravity in the fermentor is different from what's in the kettle, it's saying that the gravity of a boil done with 6 gallons leaving 0 behind is different from a boil done with 6.5 gallons leaving a half gallon behind. In both cases you will have 6 gallons at the end, but all of the sugars will transfer over in A, and some will be left behind in B. In the same volume, that would give B a lower gravity.