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eadavis80

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Really bummed on a number of levels here with this BIAB day. I started with 5 gallons of water in the 8-gallon Tall Boy and added the 10.5 pounds of grain. It fit. It was thick at the bottom, but I stirred every 15 minutes and kept a pretty steady temp between 155-160 for just over and hour. Then, I added my 3 hops additions as usual, chilled, aerated and pitched the yeast. I sparged with about 2 gallons of 150 degree water over a strainer into the grain bag which was resting in a crate over my kettle. I took my pre-pitch gravity sample and after I cleaned up I measured it and tasted it - 0-for-2. OG was supposed to be around 1.048 for this batch, but I MIGHT have been at 1.030. The taste was equally disappointing - water up front, hoppy in the middle and it burned on the back. AT this point, I'm just PRAYING it turns into something I can stomach by August, but I'm really bummed. I really enjoyed the BIAB process, but my efficiency is a joke. The taste I'm not really that concerned with, in all honesty. I was just doing this to learn the amount of water + grains I could get in my kettle, but my efficiency is very inefficient. HELP!
 
Did you leave the grains in during the boil? Your description of your process makes it sound like you did. If so that could cause strong astringency/burning.

As far as efficiency, I would start with looking at your crush. BIAB gets better efficiency with A fine crush.
 
No, the bag was removed after the 60-70 minute mash. The grains were crushed from NB.
 
Was 155-160 mash temp too high? Did that result in fewer fermentables?
 
I'm still wondering about a few things:

1. You mention "about 2 gallons" of water. Not to be nit-picky, but did you calculate the exact amount of water you were supposed to use? When you use the term "about" it makes me think that you had a general idea of how much water rather than specifics.
It is a good idea to find a BIAB calculator to figure out, how much grain, how much water based on the length of boil, the OG you want, the volume of wort you hope to produce, etc. I always recommend the BIABacus for free over at BIABrewer.info A great site for BIABers starting out.
also
2. How long did you boil for? Sometimes we boil for 60 min and sometimes for 90 min based on the base grains used. Is it possible that you calculated for a 90 min boil but only boiled for 60 min?
 
Was 155-160 mash temp too high? Did that result in fewer fermentables?

Yes, that temperature range is on the high end and you'll end up with more unfermentable sugars, ie your final product will taste a bit sweeter and will have fuller body.

By the way, I almost always mash at 156-158F as well and I also do BIAB.

With respect to your efficiency, ask your LHBS to crush your grain finer. I have a Victoria grain mill and grind my grains really fine.
 
Okay, so we mash at basically the same temp. The grains were crushed from NB. I don't think my LHBS would look too kindly on me bringing in grains purchased online and ask them to re-crush them.
 
Has anyone ever asked an online brew store to double crush? If so, did you have any luck?
 
Brewmaster's warehouse would double crush for me upon request. I don't know if they are still in business?
 
I looked at several BIAB calculators and while they were all generally close to each other, they were different even though each time I put in 10.5 pounds of grain, a 60-minute boil, I wanted 5.25 gallons of yield, figured I'd lose .25 gallons to trub and the diameter of the kettle was 12". I did what I felt was an average among the sites I looked at. I feared having the stuff overflow with that amount of grain. I knew I was not close to overflow with my previous BIAB experience, which was NB's Dead Ringer, but that one only had 7.625 pounds of grain and said to start with 5.5 gallons of water. However, in that one too, I had poor efficiency. Both of the times I did a 60-minute boil (or maybe 65) and put in 60 minutes on the online calculator. I just wish I knew if the poor efficiency was due to A) poor crush of grains B) too high a mash temp C) too many grains for that amount of water. I know I started with 5 gallons in the kettle and I know I ended the sparge with 6 gallons because I lose a gallon in an hour of boiling. I know the height the water needs to be at in my pot. Does it matter if I have the water in the mash or a combo of mash + sparge? So, if I could have fit 7 gallons in the kettle and not done a mash is that different than what I did (5 gallons in the kettle pre-sparge + 2 gallons of sparge water)?
 
Has anyone ever asked an online brew store to double crush? If so, did you have any luck?


Yes, all the time. I always ask AHS to double crush my grains. I do BIAB as well, and get great efficiency. My process is to calculate the mash water for 1.25-1.5 qts of water per lb of grain, (and typically mash between 152-157, depending on the recipe), not a full-volume mash as some do with BIAB. I stir a few times throughout the mash, then drain and squeeze the bag like it owes me something. Then I do a batch/dunk sparge step with the remaining volume needed at 160-170 deg for about 10 mins, then drain and squeeze like hell again. Combine mash wort with sparge wort and proceed to boil. I usually slightly overshoot my OG with this process. I have to adjust Beersmith for about 80-85% mash efficiency. Don't be afraid to squeeze the grain bag.
 
I'm starting to realize that everyone finds their way that works for them with BIAB. I never sparge, but then I have a 15 gallon kettle so I can use all the strike water for the mash and still fit the grains. I believe this is the best method for me, and I manage to hit my expected OG 95% of the time. I see that others have great success with dunk sparging and other forms.

I can't offer advice on sparging.
 
Does it matter if I have the water in the mash or a combo of mash + sparge? So, if I could have fit 7 gallons in the kettle and not done a mash is that different than what I did (5 gallons in the kettle pre-sparge + 2 gallons of sparge water)?

There are different schools of thought.

Some brewers will use the full boil volume to mash and skip the sparge.

https://byo.com/grains/item/1375-skip-the-sparge


I usually do a 50/50 split, ie my strike water and dunk sparge water are around the same amount. I also calculate the amount of strike water that the grain will absorb (for my system I use 0.125 gallons per pound of grain) and add that to my strike water volume.

To apply that to your recipe, let's go backwards. You want a pre-boil volume of 6 gallons. I would split that 50/50, so 3 gallons to be collected from first runnings, and 3 gallons from dunk sparging.

Add the water that the grain will absorb: 10.5 lb x 0.125 gallons = 1.3 gallons. So, your strike water volume will be 3 + 1.3 = 4.3 gallons. Dunk sparge with another 3 gallons @ 165-1700F.
 
I have two local shops to choose from, and both are strict in their crush settings, they will not adjust for BIAB or any other reason. But from either shop, I can mash what I get like a traditional mash with a sparge and get upwards of 85% efficiency. I calculate on Brewtoad, usually 1.25 qt/lb. Stir regularly, squeeze bag and combine it all.
 
The only thing I did not do was squeeze the bag. I did not squeeze it after I pulled it out of the brew kettle, nor did I squeeze it after sparging. I also did not do a DUNK sparge. Maybe I'll try those 2 things next time. But, given the math brew darrymore just gave me, I wasn't really that off his measurements. I went 5 gallons mash + 2 sparge. He suggested 4.3 pre-boil and 3 more for a dunk sparge. My next question is given the laughably low OG, am I safe in assuming a beer this light in gravity would easily reach its FG in less than a week? And, since I didn't give it that many fermentable sugars in the wort, will the horribly low OG, when it ferments leave me with an equally laughable FG? Right now, the best I can hope for is a 2.5% ABV and that's if it gets down to 1.010. But, if it stops high, I'll be left with basically an O'Douls...
 
You'll get a much higher efficiency mashing with less water and using more to sparge. Those who use a full-volume mash (no sparge) accept that efficiency will be lower but saves lots of time (the cost for extra grain is mostly only a few $$$). I only BIAB'ed a few times, but found that dunk sparging worked better for me than 'fly' sparging as the sparge water when I sprinkled tended to go down the sides of the bag (I'd crushed really fine) rather than through the grain.

Try less mash water, more sparge water, and use a dunk sparge (you can use a fermenter to dunk in if you don't have another pot). A second dunk sparge with further improve efficiency (slightly) at the cost of more time and effort.

If efficiency isn't important, adjust your grain needed to hit your target OG.
 
I just wish I knew if the poor efficiency was due to A) poor crush of grains B) too high a mash temp C) too many grains for that amount of water.

A) Possibly

B) Given the temp range you were in, this did not impact your efficiency. Your OG would be the same, but as mentioned, you might end up with a less fermentable wort.

C) Nope. 5 gallons = 20 quarts. So that's 20/10.5 = 1.9 qts/lb. Totally acceptable.

Honestly, I suspect that the sample you pulled might be the culprit. Are you using a hydrometer or refractometer? What temp are you reading at? Are you making sure you get a representative sample of the wort, is the wort well mixed?

More than once I've pulled a sample, taken a reading, only to realize my low OG was because I didn't stir everything up really well.

Last bit of advice. You should take more gravity readings during your brew day. At a minimum take one before the boil. If your gravity is short at that point then you can adjust by adding some extract. Also it might help pinpoint where your problem is. I find it informative to take readings of the mash, the sparge, and then the combination of the two. All the math should work out. If it doesn't I start looking for where things went wing.
 
So maybe 3 gallons of mash water next time and dunk sparge repeatedly until I meet my 6 gallons of pre-boil wort? I felt when stirring every 15 minutes with the 5 gallons of mash water that my mash was pretty thick and didn't know if having an even thicker mash would be bad. But, I guess given my results, it can't do any harm. Next time around, less water for the mash and double dunk sparge it is (as well as squeezing the bag).
 
Texas Wine - thanks for the thorough response. I take my readings with a hydrometer. The wort was in the mid 60's. I know hydrometers are calibrated for 60, but those 5 degrees would not make the sample THAT FAR OFF. It had to be mixed well as 1) there was no 'top off water' like there might be if it was a partial boil 2) I pour my brew kettle's content through a sanitized strainer into a bucket first and then pour the bucket's contents into my Big Mouth Bubbler as I prefer see through fermenters. I'm sure after those two pours, it would be all mixed up nicely + aerated. If I do take pre-boil gravity samples and the wort is 160, do I just put the vial in the freezer for 10ish minutes to cool it down to a reasonable range?
 
So maybe 3 gallons of mash water next time and dunk sparge repeatedly until I meet my 6 gallons of pre-boil wort? I felt when stirring every 15 minutes with the 5 gallons of mash water that my mash was pretty thick and didn't know if having an even thicker mash would be bad. But, I guess given my results, it can't do any harm. Next time around, less water for the mash and double dunk sparge it is (as well as squeezing the bag).

Like others said, 1.25 to 1.5 qts/lb of grain, so 3 gallons or a bit more for 10.5lbs of grain. Try one dunk sparge vs. two, see what the difference in efficiency is for you and decide if it's worth it. Seriously, the cost difference in a few % efficiency is negligible.
 
Yesterday I was pretty deflated about my OG, now I'm just anxious to try the process again. However, the grains I currently have are NB's Dead Ringer BIAB (3 gallon kit). Would you guys suggest I do what they say and start with 5.5 gallons of water and do no sparge, or start with maybe 2 gallons of water and dunk sparge the rest? The first time I did this kit, I was left with 4.25 gallons of 1.042 wort, not 3 gallons of 1.064 wort. Part of me says try less mash water and the dunk sparge since that will more "mimick" future BIAB attempts. I also will try to find some iodine for that pre-boil conversion test.
 
In the NB Dead Ringer BIAB kit there are 7.625 pounds of grain which allegedly results in 3 gallons of IPA. The target OG is 1.064.
 
That works out to 70% efficiency. I'd suggest a single dunk sparge. Mash with 2.5 gallons of water, sparge with whatever you need to reach your pre-boil volume.

You should go close to that OG without sparging (mash with the full volume of water) providing your crush is fine and your water is suitable and assuming that you dump all of your post-boil wort into the fermenter.
 
Has anyone ever asked an online brew store to double crush? If so, did you have any luck?

RiteBrew.com has choice of single or double crush, and double has worked very well for my BIAB process, with 72-78% efficiencies. I mash 1.25-1.5 qt/lb, but only have a 5G container, and only do "partial boil". I always do a 10m dunk sparge in 1.5G, adjusting mash volume as required to keep boil volume <=4G.

In the NB Dead Ringer BIAB kit there are 7.625 pounds of grain which allegedly results in 3 gallons of IPA. The target OG is 1.064.

I would mash 7.625*1.5 = 11.4QT water. True BIAB-ers would put in full volume, allowing grain absorb, boil-off, and boil-kettle-loss-trub-break to reach 3G into fermenter.
 
I used a NB 3G biab kit with good success once (Cascadian Dark), but I think I crushed the grain myself on my Corona Mill. If you are using NBs crush I would increase mash time (even 90 minutes or more). I personally think that any sparge gets you a point or two but no more. I would go longer mash, no sparge, full volume mash ... but that's just me .. YMMV
 
Thanks soccer Dad - now I have another option to consider... longer mash :) Like everything in home brewing, I'll just have to experiment and see what works for me.
 
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