I just want to get some things straight

[FedoraDave]

I do a lot of 2.5 gallon AG recipes, and I do them BIAB, because I don't feel like schlepping out the mash tun and doing all that extra washing.

I know BIAB is supposed to be a full-volume, one-pot process, but here's what I've been doing:

I calculate my strike volume the same as I would if I was using a mash tun, i.e. 1.25 quarts per pound of grain. Usually I have about 4-5 pounds for a 2.5 gallon batch. I heat the strike water to about 5-10 degrees higher than I want my mash temp, and then stir in the grains. After mashing in, I make sure my temperature is where I want it, put the lid on the pot, and then wrap it in three towels for insulation and let it sit for an hour.

I then drain the bag, and I squeeze the heck out of it, even using the pot lid to coax as much of the first runnings out as possible. I know from experience that I'm going to get about half the original volume back.

Then I do a sparge in another pot with the amount that will make up my pre-boil volume. This is a 15-minute sparge, and I squeeze the snot out of this, as well, to get as much of the wort out of the grains as possible. Then I combine the two pots and go ahead and brew.

I've been getting good beer doing this, and maybe I'm making a little more work for myself (although not as much as a full-volume 5-gallon mash). So I'm thinking this may just be a case of Brewer's Choice. I do like the idea of a sparge, though. I feel as if I'm drawing off more fermentable sugars by doing this.

Another question for me would be, were I to change to a single, full-volume BIAB, exactly what my strike volume would be. I've gotten comfortable with the numbers I've been working with by using this technique, and I'm not eager to re-learn volumes just to fit in with the recommended technique.

[mashani]

I see no harm in what your doing, it should work fine. There are lots of ways to do it.

To do BIAB as the Aussies intended (full volume/no sparge), you want to use as much strike water as is needed so that when you pull the bag your entire boil volume is what is left behind in the pot. You simply mash and then boil. The easiest way to figure that out is to use an online BIAB calculator (Beersmith probably has one built in too?) that figures in the amount of water absorption per # of grain. You can get 70% efficiency doing that if you stir the grains from time to time.

But this implies you have a pot that is big enough to hold all the grain and all the water necessary to do this. Which I do not.

So I do it in the middle between what you do and traditional - not full volume, but with more water to grain then I'd do in a traditional mash. And then make up the water difference in the sparge which I do by repeatedly "dunking" the bag in the sparge water like a t-bag, which I then add to my pot. IE I mash in 16Q pot, sparge in 12Q pot, and add it all back to 16Q pot. My pot is big enough to hold full volume for 2.5 gallon boil - but not the grain AND that much water. And I will top up with water as needed too, I don't bother trying to make it work out perfectly, I just make sure I'm not going to go over - it's not worth the bother, it makes beer regardless.

[FedoraDave]

Thanks. I wound up with this technique because, while I have an 8-gallon pot, which I use for 5-gallon batches, I'd prefer not to use it for 2.5 gallon batches (again, I'm fairly lazy and don't want to haul that heavy pot around). But my 5-gallon pot, while good for the boil, won't handle a full-volume BIAB mash + grains. But with only about 1.5 gallons of strike water, my 3-gallon pot works just fine for the mash, and the 5-gallon pot works best for the sparge. This seems counter-intuitive, but since the grains are soaking up half the water in the mash, and none of the water in the sparge, it actually works out quite well.

I'm still working on understanding all the ins and outs of BIAB, even though I'm doing at least half my pipeline this way. But, as you pointed out, there are lots of ways to do it.

I still like to sparge.

[John Sand]

Dave, I do about the same as you. I use the same method for 5 gallon BIAB. I don't think it wastes any time, as I am heating my first runnings to a boil as I'm sparging.

[The_Professor]

I have a fairly new Darkstar burner and a 30 quart pot.

Previous to this I step mashed my 3ish gallon batches in (I think) a 15 quart pot then sparged using a mesh lined 6.5 gallon bottling bucket.
So far I have stuck with my 3 gallon batches but done a single infusion mash in an insulation covered 6.5 gallon fermentation bucket (no spigot) and then done the usual sparge in the mesh lined bottling bucket. I'm sure I can kick the volume up to 5 gallons using this method. So, yeah, no cooler conversion to make a mash tun.

But it occurred to me that I could do a 3 gallon BIAB using my new equipment. I simply used the same amount of water that I usually used by the other method (5gallons) except I used it all at once in the 30 quart pot. I heated the water to "strike" temp, stuck the bag in the pot, added my grain, stirred well and covered it. I stirred a few times and I mashed for 90 minutes as I had read this was best. The only sparge was allowing the grain bag to drain well. Post boil I hit my OG really well, but it turned out my volume was a bit low so the efficiency was not quite as good as it seemed.

So long as your mash is good and you are getting the sugar from the grain in your wort you're gonna get good beer. Just a question of being realistic of your efficiency in making your recipes. Just rambling, maybe adds to what you're asking...

[Crazy Climber]

I do something similar to you, Dave, but I do it in an effort to keep the water:grain ratio from getting too water-heavy. (I can fit a full-volume mash, but choose not to.)

I know that full volume BIAB mashing obviously works, but I've also read that thinner mashes can be less efficient and/or produce less-fermentable sugars resulting in a higher FG (too tired/lazy to look it up now, sorry).

One of these brew days soon, I'm going to mash a full volume, but thus far I've hedged my bets by holding back and dunk-sparging, to maintain a thicker mash.

Many ways to skin the BIAB cat.

[ScrewyBrewer]

I've been working backwards in figuring out my water volumes. I first figure out how much beer I plan to package. Then I add to that the amount of wort loss to grain absorption and hop absorption. To that volume next I add in how much wort will be boiled off and finally the amount of kettle trub that'll never go into my fermentor(s). I use a BIAB calculator to help me figure out the numbers here.

I always have a pot of 170F sparge water handy at the end of the mash to pour through the grain bag and into the kettle before starting the boil. I also keep some water boiling near the end to top off the kettle volume when needed. My grain basket fits neatly inside my old 10 gallon kettle, with the old kettle on the floor using a lid from a smaller pot I lean down and press the hell out of the grains and then dump the run off into the kettle too. I may not set any records for the quickest or least complicated BIAB brewday, but I love the beer that I get to drink a month later.

[FedoraDave]

One of the things I wondered about was the recommendations I've seen to double-crush the grains for BIAB, to help increase efficiency. I can see how that would be beneficial for the traditional BIAB one-pot/no-sparge technique, but with what I'm doing, it seems double-crushing is unnecessary. There's no doubt my sparge rinses out some more sugar from the grain, and I seem to be getting efficiency close to 75%, as I'm usually within a couple of short hairs of the projected OG.

As Mashani pointed out, there are a number of ways to do it, and I'm getting beer, so hey.

[Beer-lord]

I don't double crush and never have and I am almost always where I need to be with beers under 1.075.
And I also squeeze the bags very well.

[Rebel_B]

I don't double crush and never have and I am almost always where I need to be with beers under 1.075.
And I also squeeze the bags very well.

I do a modified BIAB as well; no double crush, no squeezing the bag. I have been mashing at 1-1/2 quarts/lb ratio. Efficiency has been ranging +/- 70% on most of my beers lately. I'm happy with the results I've been getting!

[Beer-lord]

Just my 2 cents on bag squeezing......everything I've read, especially the last 2 years, has said that there is not a problem with bag squeezing. Sometimes I squeeze hard, sometimes not, depending on how much liquid I need.
But, I rarely sparge unless I need to get much higher gravity.
Rebel, with that ratio, it appears you sparge. If so, do you do a dunk or pouring hot water over the grains to get the goodness out of them?

[FedoraDave]

Okay, well, I squeeze/press the bejabbers out of the bag to get as much first runnings as possible. I even use a cookie cooling rack over the pot while I press down on the bag with the pot lid.

Same with the sparge. I want ALL THE LIQUID! And I do my sparge as follows; I've got the water heated to 170-175, and I submerge the grain bag, stir the grain to get as much circulation as possible, cover the pot, turn off the heat, and let it sit for 15 minutes.

Then I do the squeeze/press the bejabbers thing again.

I read years ago that the tannin thing isn't really an issue with small-volume brewing, and since my BIAB batches are 2.5 gallons, I'd have a tough time getting much smaller than that. Never had a problem, either, so I'll press on. (see what I did there?)

[Rebel_B]

Just my 2 cents on bag squeezing......everything I've read, especially the last 2 years, has said that there is not a problem with bag squeezing. Sometimes I squeeze hard, sometimes not, depending on how much liquid I need.
But, I rarely sparge unless I need to get much higher gravity.
Rebel, with that ratio, it appears you sparge. If so, do you do a dunk or pouring hot water over the grains to get the goodness out of them?

Yes, I sparge by pouring 170 degree water over the grains to get to pre-boil volume.

[ScrewyBrewer]

I read years ago that the tannin thing isn't really an issue with small-volume brewing, and since my BIAB batches are 2.5 gallons, I'd have a tough time getting much smaller than that. Never had a problem, either, so I'll press on. (see what I did there?)

I agree I don't even think about extracting tannins when I'm collecting my wort, just the extra sugars I'll be getting. Since doing eBIAB I've dispelled several other myths that are out there too. Like getting cloudy wort for instance, apparently the best way to tell what's real and what's not is to just get in there and brew it.

[MrBandGuy]

Resurrecting posts...new around here. Anyway, I have done the same as you, Fedora, for the past 3 years. Mash in 1 pot, mash out/sparge in another exactly as you described. I've never worried about grain/water ratios, usually reserving 2.5G for the sparge pot, the rest for the mash. The mash out step is key for me for 70% efficiency. I double crushed for a while, but didn't see much difference. And I squeeze they bahooey out of both.

I've since upgraded to a 10G pot and a toile bag. Full volume is possible, and just as good. Haven't made a huge beer yet, but figured if I need more room, I can use 2 pots again no problem.