So i've done 5 recipes with the BIAB method an I wanted to know if i can make two beer out of one grain bill? And if so does anyone have a video/tutorial on how (I'm a visual learner).

you would need to do some kind of sparge to do this (called partigyle by the way) but I don't see why not. I would just do the biab and get the first wort done with no sparge, then sparge to get the 2nd wort. I would get a super fine crush to get good efficiency so you don't need all the sugars to get the first wort up to OG.

I had contemplated this too. your 1st beer would have to be pretty big in order to get a decent 2nd beer. something like an imperial IPA (with a target OG of 1.075-1.080) with the 2nd beer being an american mild/light pale ale (OG in the 1.035-1.040 range).

or make the 2nd running a smaller batch by boiling longer to evaporate more water and condense the sugars....could probably bump the OG of the 2nd beer into the mid 1.040s, but obviously lowering your yield in the process.

speaking of process, I would just do the normal BIAB for beer one, but then move the grain sack right into the pot for beer 2 (without mashing out for the 1st beer), and letting that steep for like a half hour or so at like 151°, then raise up to 170 and mash out for 10, drain the sack and boil away!

I guess I thought differently about the question. After the mash, split into 2 kettles with different hops, different yeast, etc. Or simpler, after boil split to 2 fermenters with different yeasts, dry hops, etc. Not twice the beer from one grain bill, but 2 different beers.

I see no problem with that. I have split post boil to try different yeasts.

yeah, a 10 gallon BIAB of a pretty generic grain bill of 2 row and a medium crystal... split into two five gallon batches... one boiled with english hops and fermented with S-04 would produce a nice english pale. the other five gallons boiled with a healthy hop boil of american "citrus" hops and fermented with US-05 would give a nice IPA. kind of similar, but kind of different at the same time.

Thanks for the advice, bu I was thinking more of how when people collect the "second" runnings of wort and use that as a possible table beer or small beer. That is what my goal is, or is this not possible with BIAB at all?

Meh... Unless you have a way to drain the wort runnings through a valve on your brew pot... Probably won't work with just lifting the bag to another pot... Since the mash is so loose in BIAB, you might not get enough sugars to carry over.

Nah, you can totally do it with BiaB. Cards and Natty are both on the right track.

The question is do you want a strong and small beer or 2 normal strength beers?

With a large grain bill you can make (first) one strong beer and (second) a weaker beer, or (if you have a way to reserve the wort) you could combine the efforts of a large grain bill for either a larger batch or two smaller batches (perhaps slightly different).

patigyle has a lot to do with volume... it uses a ton of grain to get a high OG wort from the first running (like natty said)... with only two or three smaller volume runnings combined to get a lower gravity second beer... we're all in agreement on that.

but, here's where my thoughts differ (and these are just my thoughts... take it for what you think they're worth)... if you do a full volume BIAB mash, then there's not much to go around for another wort since you're getting all the "volume" that the gravity points can fill out of the way in one go... if that makes any sense.

if OP does a large grain bill in the first BIAB then yes, it *might* work... similar to what natty and CF suggested. but i'd bet if it's just a regular old full volume BIAB, then put the grain bag in a second pot with a full volume of strike/mash/sparge water, there wouldn't be a lot of sugars left to get a good gravity in a new pot of water. it's a good idea... i feel like there's left over sugars i'm getting when i do BIAB, too. but unless you "sparge" in the second pot and add some DME to hit a high enough gravity... i don't think it'd work. but like i said, that's just my thought.

I totally agree.

However if you are NOT full volume your second go around would be like a sparge of the grain for a weaker wort. Combine the two and there you have it.

Thank you for all of the help, it sounds like this is maybe but I am definetly going to give this a try saturday morning and see what happens. Professor I am shooting for a Big Beer and then a Small Beer effect. The BIAB method is pretty easy and its great on space as I live in a condo. PSUChunk, I definetly understand what you are saying, but now another question has come has arose. Could I use fruit or something to "cheat" along with the DME/LME to get more sugars? I ask about the fruit since it's going to be a small beer I might as well make it for my wife...

A lower OG beer would be thinned out by the simple sugars that a fruit addition would bring to the mix. I would keep some DME on hand to get the gravity up in case the second wort isn't as big as you're hoping for... Then do a drug addition once the OG was high enough to support a simple sugar addition.

What about overshooting the volume on the "first runnings", then blending some of that with the weaker sparge water?
Example (these numbers are totally made up and not realistic!):
Make 3 gallons of 1.070 wort. Sparge 1 gallon and get maybe 1.010. Take 1 gallon of the 1.070 and add to the sparged gallon and get 2 gallons of 1.030.
Just a thought.

Here's a thread that may give you some info:
"Saturday I did 2 batches, attempting to get a higher gravity (brandy wine) and a mild. I was shooting for 10 gallons total, but wanted a milder brew at around 3-4% that I could drink in a 2-3 weeks, and a heavier beer to age for several months like a brandywine."
BIAB Parti-gyle

nice...I had been looking at like a dozen similar threads "over there" as well! seems like a decent idea, and I'm gonna try it later on this year (got 7.5 gal conditioning, slew of single bottles, and a combined 3 gal at least in my kegerator, along with ingredients for 5 more gallons just sitting here waiting! hmmm...MBFans party at my house?) when I've got the time/brew room to do so!

It appears this method does not work

Nah, it definitely works...your small beer had a gravity of something like 1.032, right?

Because that's definitely in the realm of what people are looking for when they go partigyle.

Well I tried it and now I'm just relaxing and not worrying about what's in the closet, i'll try it in two weeks...

Good plan :-)

what did you end up trying?

I did a blonde ale from brewing classic styles