Thanks! I am going to check that out right now. Also I may just go out and boil for an hour and calculate based on that... something about plugging in arbitrary numbers is unsettling to me.
So how much water should I start with? I have a 10 gallon megapot that has a 17" diameter. I have an extra bucket which I'll use with a colander to get the remaining wort out of my bag, and will be re-adding that remaining wort back into my pot.
I've only done extracts so far and I've always started with around 6 gal and ended up with 5 in the fermenter. I'm assuming this would be about the same but I'm not sure with grain absorption...
Any help would be appreciated!
simple math here...that's all it takes.
absorption + batch size + boil off + trub loss = water needed.
absorption = grain weight in pounds * 0.06
here's an example from my last batch. oatmeal stout using 14 pounds of grain. I know my boil off rate in my 10 gallon pot is 1.25/hr and trub loss is 0.25 gallon. this was for a 5.5 gallon batch
14*0.06 = .84 gallons of water absorbed by grain (this accounts for me squeezing the bag. if you squeeze harder use a smaller number, if you don't squeeze at all use a larger number)
0.84+5.5+1.25+0.25= 7.84 gallons.
I rounded this up to 8 gallons to make it easier to measure. I could have gone down to 7.75 and still be fine. One you know your boil off and trub loss, this will be a simple part of the brew day. it takes just a few seconds and will be fairly accurate. I hit my numbers on the nose last batch, as well as the 20 before it..
simple math here...that's all it takes.
absorption + batch size + boil off + trub loss = water needed.
absorption = grain weight in pounds * 0.06
here's an example from my last batch. oatmeal stout using 14 pounds of grain. I know my boil off rate in my 10 gallon pot is 1.25/hr and trub loss is 0.25 gallon. this was for a 5.5 gallon batch
14*0.06 = .84 gallons of water absorbed by grain (this accounts for me squeezing the bag. if you squeeze harder use a smaller number, if you don't squeeze at all use a larger number)
0.84+5.5+1.25+0.25= 7.84 gallons.
I rounded this up to 8 gallons to make it easier to measure. I could have gone down to 7.75 and still be fine. One you know your boil off and trub loss, this will be a simple part of the brew day. it takes just a few seconds and will be fairly accurate. I hit my numbers on the nose last batch, as well as the 20 before it..
MMJfan said:I thought the point of doing BIAB was to save time? Three hour mash? No thanks...
I've.done several BIAB batches and never gone more than 60 minutes and sometimes less. No problem. Not sure what's up with the Aussie 3 hour mash.
I have a 7.5 gallon pot. Could I do 4 gallon batches using this method? The reason I ask is I have two 5-gallon glass carboys that I would like to use as primary fermenters.
Please forgive me if this was already asked and answered in the thread. I didn't have time to read through the whole thing!
Yes is the short answer, however w/ bigger grain bills, the more you colander "sparge" , your efficiency may suffer due to technique....but your on the right track cheersIf I wanted to do a 5 gal batch in a 7.5gal pot, can I just put the grain bag into a colander and sparge with water at 170F to the pre-boil volume (~6gal)? If this is the case, the limitation would be how much grain you can mash (per http://www.rackers.org/calcs.shtml).
.
And a 2nd question. When steeping, Palmer and others say not to squeeze the bag to prevent extracting tannins. But, many posts on this thread suggest doing just that. Is Palmer just out of date? Do you not have to worry about it as long as the temp is low?
:
And a 2nd question. When steeping, Palmer and others say not to squeeze the bag to prevent extracting tannins. But, many posts on this thread suggest doing just that. Is Palmer just out of date? Do you not have to worry about it as long as the temp is low?
Cheers!
Think of it this way: the grain bed of a massive commercial brew (BMC) is going to put more pressure on the grains than you will ever achieve. BMC beers are not known for their astringency or tannins. As long as your pH and temp are reasonable, you really don't need to worry. I've been doing BIAB for the last four years, squeezing the bejeezus out of the grain, and have never had tannins.
That makes sense. So, I should be squeezing specialty grains as well (for extract brewing)?
I have a 7.5 gallon pot and have gotten the following effieciencies for recent batches:
Oktoberfest, 11 lbs grain, 77% Efficiency
Brown Ale, 8.5 lbs grain, 80%
Scotch Ale, 13 lbs grain, 76% (not including 1 lb of DME)
2 Hearted IPA, 12 lbs grain, 77%
I can exceed 80% generally when I mash 9 lbs and below. Have gotten as high as 86% on a Kolsch. But I am generally 75-82%. I do a pseudo drip sparge by suspending grain from rope/pulley in fryer basket above brew kettle. If you have a second vessel, you can get another 3-5% by dunk sparging for 10 minutes, but I generally don't bother any more.
slcdawg said:Do you do a mash-out at 170F for 10 minutes as part of your process? And then just top off with water to get the right pre-boil volume?
scook13339 said:Just jumping in...
I usually kick the temp up to 170f and hold for 10 min.
In my standard process I plan to add <2 liters to the kettle to get to the preboil volume. I'd rather top up then boil off. It's a matter of time.
Antler said:I've read that this is the wrong idea for mashout. I think you supposed to bring this from mash temps to 170f over 10 minutes, not hold it at 170 for 10 minutes.
I may be wrong but that's what I read and that's how I do it!
Truth is, it probably doesn't make a lot of difference. Mashout is a highly optional step. After I read your reply a checked in Palmer's How to Brew and he says really doesn't make a difference for loose mash 1.5 qt to lb or more. BIAB mashes are much looser then that.
My question is for those that use a 7.5 gal kettle, what is your method to get the necessary pre-boil volume? Say the recipe is 12 lbs of grain and you lose 1 gal to grain absorption. With a 7.5 gal kettle I can only mash with ~5 gal of water - which will leave me ~2 gal short. Which method do you use?
A. Mash-out at 170F. Top off to pre-boil volume
B. Skip Mash-Out. Sparge with volume of water to reach pre-boil volume
C. Mash-out and Sparge
D. Other?
first.. you'd lose .72 gallons.. less if you squeeze the crap out of that bag..
second.. sparge with 170F water.. either by pouring through grains and then squeezing.. or dunk sparging... followed by squeezing
My question is for those that use a 7.5 gal kettle, what is your method to get the necessary pre-boil volume? Say the recipe is 12 lbs of grain and you lose 1 gal to grain absorption. With a 7.5 gal kettle I can only mash with ~5 gal of water - which will leave me ~2 gal short. Which method do you use?
A. Mash-out at 170F. Top off to pre-boil volume
B. Skip Mash-Out. Sparge with volume of water to reach pre-boil volume
C. Mash-out and Sparge
D. Other?
Thanks. So, do you mash-out and sparge? Or, just sparge?
Do you do a mash-out at 170F for 10 minutes as part of your process? And then just top off with water to get the right pre-boil volume?
I don't hold at mashout temps, but it does take 10-15 minutes to get there from my propane burner.
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