BIAB -- am I doing it all wrong?

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z-bob

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I've been brewing all-grain for a few month now, and I've been reading at biabbrewer.info and wonder if I'm doing it wrong. I am brewing 4 gallon batches (that's what I can do on my kitchen stove) and I have a couple of 22 quart pots (one is a thin stainless steel stockpot and the other is thick aluminum canner), and an electric 5 gallon bucket that I made for a very fast but crude HLT.

I bring 4 gallons of water up to about 165 degrees and pour half of it in the canner which has a bag in it. Let the temperature stabilize, then dough-in the grain. I mash for about an hour, do an iodine check to make sure, then pull the bag out and squeeze the dickens out of it. I transfer the bag to the stockpot, which has the other 2 gallons of 170 degree water, stir it gently for a few minutes, then pull it out and squeeze again. I combine these two squeezings and bring to a boil, etc. I'll add top-up water to the fermenter to get it back to 4 gallons.

Does it really work just as well to mash in the entire 4 gallons of water and skip the sparge? How much sugar do I lose to the spent grain? Or is that negligible, and offset by a more efficient mash?

I need to move outdoors for the summer anyway and will be making changes for that, so it's a good time to review my whole process. Mashing a larger volume would make it a lot easier to maintain a steady temperature... (I'll probably still do the mashing on the kitchen stove, that doesn't heat the house up all that much)
 
So I'm doing an unnecessary step, and also making my mashing step more difficult? :D Sounds about right.

Well, short answer is yes. Some believe you will have an efficiency gain by sparging, others don't???

I believe it is a helluva lot easier to not bother sparging, or do a small pour over sparge with the bag above the kettle, also handy to adjust volume to preboil volume.

Topping up the kettle with water should be a last resort and done only if you are limited w/ kettle size or boil volume.

Grain is not that expensive, I wouldn't sweat your efficiency as long as it is "reasonable", say above 65-70 due to your limitations on boil size...jmo

Ever think about just doing 4 gallon batches, or are you buying kits?
 
So I'm doing an unnecessary step, and also making my mashing step more difficult? :D Sounds about right.

I've been doing something similar to you with a slight difference but am considering switching to the full volume mash. I have a large 10 gallon cooler that I bought intending to make a MLT out of it, then I discovered BIAB.

I've had issues with very cloudy wort with "traditional" BIAB, so I thought, why not use the cooler with the bag in it and vorlauf? plus the cooler helps maintain mash temps. I have still done a more traditional 1.5qt/lb mash with a sparge afterward though. I guess I'm not really saving myself any work with the BIAB method either, but the vorlaufing helped clear the wort!

Now I need to try it with a full volume mash and see if I run into any snags in my method.
 
Cloudy wort does not mean cloudy beer. BIAB cloudy wort will make nice clear beer given enough time and cold storage...RDWHAHB

I've certainly read that, but I've also read a number of (disputed, of course) issues with flavor stability associated with the extra proteins and whatnot in the "cloudyness." I've seen quite a few opinions on both sides so I figured, why not go with what seems "safer" to me. I certainly enjoyed the beers I made with cloudy wort, and they didn't last long enough for stability issues to manifest :p
 
Ever think about just doing 4 gallon batches, or are you buying kits?

Not sure what you mean. I am doing 4 gallon batches. I start out with about 4 gallons in the kettle (maybe a *little* less) and I lose a half a gallon to evaporation. Then I top up the fermenter to get 4 gallons again -- except the time I did a 3 gallon big beer. (I boiled that down to 3 gallons and then didn't top it up)

My next purchase will be a propane burner (Bayou Classic SP10 is a contender) and then I'll be able to boil larger batches if I buy a larger kettle. But 4 gallons is a good size so I don't know that I'll step it up.

I'm not buying kits, I'm making up my own recipes as I go. I bought a 50 lb sack of pale ale malt, so I use that plus a little specialty grain from the local homebrew store. I haven't settled down on a "house" beer yet, I'm still playing.
 
I've certainly read that, but I've also read a number of (disputed, of course) issues with flavor stability associated with the extra proteins and whatnot in the "cloudyness." I've seen quite a few opinions on both sides so I figured, why not go with what seems "safer" to me. I certainly enjoyed the beers I made with cloudy wort, and they didn't last long enough for stability issues to manifest :p

I'll dispute that as well. The trub from BIAB tends to settle out rather quickly, especially if you use a fining agent, like Irish moss or Whirlfloc. If that cloudiness has settled, and you rack carefully when packaging, I don't see how you would have anything that would alter the flavor of your beer.

I think that's an old urban legend among a few brewers.
 
Both will make beer, neither is "wrong". Some steps are just slightly unncessary under most circumstances, and this is the main difference in my experience between HBT and biabrewer forums.

Biabrewer: No no, that's wrong. You have to mash full volume, for 90 minutes with a 90 minute boil are it's going to taste like cat piss.

HBT: Sure, you can sparge if you want to/have to. Both will be beer, although full volume is faster and easier as it eliminates an extra step.

My advice is usually to mash with as much as you can, leaving a little room to stir the mash and dough in thoroughly. I don't experience any gain from sparging, but some people do.
 
If you can fit all the water and grain into your pot, then do a full volume BIAB. There is really not enough of a difference to do a batch or dunk sparge with most batches. I do perform a batch sparge when I am doing high gravity recipes as (1) the lower efficiency and (2) the added grain from these higher gravity brews brings me too close to the lip of my kettle for my comfort.
 
I can't speak for anybody else...........everybody has their own technique...... but I've seen massive increases in efficiency from dunk sparging.

I perhaps don't measure my efficiency the same way you do...... I measure OG at the fermenter with the projected amount of wort..........you may measure it differently. That difference is irrelevant as long as we measure consistently......an increase is an increase, and a decrease is a decrease. The biggest factor for me was moving to a BC instead of using LHBS crush. Next it was dunk sparging.................


H.W.
 
Absolutely, dunk sparging increases efficiency. But full-volume mashing should also increase efficiency. Is there a noticeable difference between the two? I don't know; I can see where it might be a wash. (Sorry!)
 
I've been doing something similar to you with a slight difference but am considering switching to the full volume mash. I have a large 10 gallon cooler that I bought intending to make a MLT out of it, then I discovered BIAB.

I've had issues with very cloudy wort with "traditional" BIAB, so I thought, why not use the cooler with the bag in it and vorlauf? plus the cooler helps maintain mash temps. I have still done a more traditional 1.5qt/lb mash with a sparge afterward though. I guess I'm not really saving myself any work with the BIAB method either, but the vorlaufing helped clear the wort!

Now I need to try it with a full volume mash and see if I run into any snags in my method.

Cloudy wort has nothing to do w/cloudy beer. I BIAB and cold crash all light colored ales and they are crystal clear.
 
Question to those who do full-volume mashes: wouldn't the full volume strike water create too thin of a mash? Palmer claims that thick mashes of 1-1.3qt of water per lb of grain would lead to a full-bodied beer, while thinner mashes would make more fermentable wort that leads to dry beer.

What's your experience?

I dunk sparge, by the way.
 
Question to those who do full-volume mashes: wouldn't the full volume strike water create too thin of a mash? Palmer claims that thick mashes of 1-1.3qt of water per lb of grain would lead to a full-bodied beer, while thinner mashes would make more fermentable wort that leads to dry beer.

What's your experience?

I dunk sparge, by the way.

You need to think of full volume as including your sparge water. It's really the only thing that makes it unique. The resultant wort should be the same as the other brewing techniques.
 
As long as you're producing sugary goodness, I'd say you're not doing anything wrong.

For myself, I mash in a 3 gallon pot, and boil in a 10 gallon tamale steamer that's too big for my grain bag. I use another pot to hold my sparge water. I can't really do a full volume mash, and my LHBS won't do a double crush or a fine crush, so I really just imitate a classic 3 vessel setup with a 1.25 lb/qt mash thickness. Except when I pull the grain bag out, I get a lot more space in my mash pot due to water displacement, so I can just put the bag in a heavy duty colander set on top of the mash pot, pour my sparge over that, combine it all, and boil. It's a bit complicated, but I produce great wort at a very high efficiency.
 
Question to those who do full-volume mashes: wouldn't the full volume strike water create too thin of a mash? Palmer claims that thick mashes of 1-1.3qt of water per lb of grain would lead to a full-bodied beer, while thinner mashes would make more fermentable wort that leads to dry beer.

What's your experience?

I dunk sparge, by the way.

I haven't noticed a problem with body in my beers and I do full-volume no-sparge BIAB. Where it is of relevance is in regard to mash pH. A thinner mash is often used intentionally with darker grists to keep the target mash pH in the correct range. Little or no adjustment to mash pH is needed with dark grain-bills in my setup.

With lighter grists and a thin mash the pH can and do reach levels that are not desirable without something being done. This is easily rectified with the right amount of acidulated malt or acid. (Lactic acid is often used). I prefer to use acid malt but both are equally effective in lowering the mash pH to the desired range.

Does a mash pH that is too high contribute to a thinner body? I don't know. Hopefully someone more knowlegeable will chime in.
 
Cloudy wort has nothing to do w/cloudy beer. I BIAB and cold crash all light colored ales and they are crystal clear.

Oh, I wasn't saying that it did, though I don't have the option to cold crash being confined to an apartment kitchen. The main reason I was going for clear wort is the urban legend (as described above) about flavor stability from all the proteins remaining in the beer.

As other have pointed out, this is likely a myth and I'll probably just start doing 3/4 volume BIAB with a brief rinse-sparge and a squeeze (because I find something satisfying about slightly boosting my efficiency).

In the end, I have to play with my process and see what makes the best beer, according to my own tastes. After all, that's what its all about! :mug:
 
The main reason I was going for clear wort is the urban legend (as described above) about flavor stability from all the proteins remaining in the beer.:


Long term flavor stability is much more a valid concern for commercial breweries. At the homebrew level not so much .... Worry about making tasty beer first, then perhaps be concerned about stability.
 
Long term flavor stability is much more a valid concern for commercial breweries. At the homebrew level not so much .... Worry about making tasty beer first, then perhaps be concerned about stability.

I already do make tasty beer my friend, been brewing extracts for years ;) just new to all grain and learning the ropes still
 
Long term flavor stability is much more a valid concern for commercial breweries. At the homebrew level not so much .... Worry about making tasty beer first, then perhaps be concerned about stability.

Thats a good point, as I've said, I'm pretty convinced of the error of my ways and I already do make tasty beer my friend, been brewing extracts for years ;) just new to all grain and learning the ropes still
 
Batch sparge efficiency gains are calculable. Dunk sparge is a form of batch sparge where you are rediffusing to an equilibrium sugar density. In a typical 10 pound grain bill for a 5 gallon batch, a dunk sparge is worth a gain of around 6%. The downside is the need to more closely watch your pH during the dunk since the second body of wort will be a very low gravity (around 1.015). If you see greater than an 5-6% efficiency gain, it's probably a slight increase in conversion efficiency happening right at the end. Are you using HOT sparge water?
 
That's a great question to raise Bobby. I forgot to heat up my dunk water and used tepid water instead and my OG was identical to using hot water along with the benefit of being cool to the touch when squeezing the bag.
 
That's a great question to raise Bobby. I forgot to heat up my dunk water and used tepid water instead and my OG was identical to using hot water along with the benefit of being cool to the touch when squeezing the bag.

That's pretty interesting, is there any downside to using cool sparge water such as conversion control, or flavor changes?
 
The conversion was WAY over by then, the flavor was identical. I'm brewing a new batch tonight, I'll compare it with the batch in the keg.
 
That's pretty interesting, is there any downside to using cool sparge water such as conversion control, or flavor changes?

If your conversion is complete, then there is no downside to using cool sparge water. You cut off the enzymatic action (to fix the sugar profile) in the first runnings by starting the boil heat up as soon as you get the bag out of the BK. If your sparge water cools the mash below 130°F, then you will also cut off enzymatic action during the sparge. But stopping the enzymes in a batch sparge is not as important as for a fly sparge, since most of your sugar is in the first runnings, so the sugar profile of the sparged wort is less important.

Brew on :mug:
 
+1

Just found that out the hard way :cross:

With your grain bill and strike water volume it is possible to calculate what the SG of the wort in the mash should be at 100% conversion. I give an example here. You can then monitor your mash completion by taking gravity samples (a refractometer is very convenient for this.) It's a good idea to stir before taking the gravity sample. You need to be accurate on your grain weights and water volume for this to work well.

Brew on :mug:
 
With your grain bill and strike water volume it is possible to calculate what the SG of the wort in the mash should be at 100% conversion. I give an example here. You can then monitor your mash completion by taking gravity samples (a refractometer is very convenient for this.) It's a good idea to stir before taking the gravity sample. You need to be accurate on your grain weights and water volume for this to work well.

Brew on :mug:

Being kind of a 'by the book' guy myself, I shoot for the SG I am looking for and than stop and "wash the bag". I don't find that the SG changes enough to affect the beer.

Always, YMMV...
 
Being kind of a 'by the book' guy myself, I shoot for the SG I am looking for and than stop and "wash the bag". I don't find that the SG changes enough to affect the beer.

Always, YMMV...

If you are doing full volume mash (no sparge) then your pre-boil SG will be the same as the mash SG I talk about in my post above. If you do a sparge, then the pre-boil SG will be lower than the mash SG. If you are trying to diagnose a mash efficiency problem, you need to know your mash SG.

Brew on :mug:
 
I have a pot that will only allow a certain size mash, but when I take the BIAB out, that gives me room for additional boil water. That water comes from my second pot, which is the dunk sparge pot. I did that on my recent batch, and was able to noticeably see the tasty sugary goodness from the dunk sparging.

I recently read, I believe it was in the paperback the "Homebrewers Answer Book, a Q&A on homebrewing", where there was a specific ratio of water to grains for mashing, which was seen as the best ratio for the enzymes to have good contact with the starches. A larger amount of liquid diluted the mash and made it harder for the enzymes to come in contact and convert the starches. Something to that effect, which thereby assured me that my dunk sparging was not a waste of energy as opposed to topping off the boil pot with plain water.
 
A larger amount of liquid diluted the mash and made it harder for the enzymes to come in contact and convert the starches. Something to that effect, which thereby assured me that my dunk sparging was not a waste of energy as opposed to topping off the boil pot with plain water.

This commonly held view has been shown by the braukaiser among others, not to be the case. Thinner mashes do not have a detrimental effect on the enzymatic action in the mash. They have been shown to result in higher efficiency in the same experimental setup.

A sparge will always give you better efficiency over a top up with water alone. That is an entirely different situation though. Totally unrelated to the enzymatic dilution you are sugesting. Diluting the wort with water extracts no sugars and reduces efficiency. A sparge would be preferable.

I do full volume, no sparge mashes without problems from an efficiency or fermentability standpoint.
 
I'm gonna try it today, shooting for 4 gallons.

I have a 22 quart canner; I'll put in a little over 3 gallons of hot water, add the grains, then fill to the top with more hot water to mash (don't know how much that will be.) Pull the bag out after an hour and squeeze it good, boil however much liquor I get, and top it up if necessary in the fermentor.

I'm sure there are calculators that will take a lot of the guesswork out regarding how much water to start with. I know my kettle is a little small and I have to work around that.
 
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