OG too low
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If you have extract handy, you can add some. Here is a link http://merrycuss.com/calc/gravityadjustmentextract.html
ArkotRamathorn
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Did you adjust your reading for temp? As well did you do full volume no sparge? I don't have the room usually for that so my mash thickness is really high, I have to usually dunk sparge and try to wash out as much as I can so my boil volume is higher this seems to work for me to get better efficiency.
Your OG is so low, I wonder if you got low conversion efficiency. Maybe a coarse crush.
ArkotRamathorn
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Generally speaking the conversion is completed within a couple minutes of the malt hitting the water, there is at least one episode of Brew Strong I remember listening to where they test this. The 90 minute vs. 60 minute mash probably won't do anything for your efficiency.
What I do to help improve efficiency when I'm going to take my bag out, I have it in a big metal bucket strainer that fits inside my kettle, so I pick it up and dunk it back in a couple times, take a spoon and stir the mash around, dunk and sumberge a couple times, stir, dunk and submerge, and do this a handful of times. I can't do full volume so I also have to sparge some to reach desired volumes.
Since you did full volume I really doubt it has to do with mash length and more to do with the grind.
MindenMan
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I just did my first BIAB, after being AG for two plus years. I used the "recommended" volume of sparge water, and checked my pre-boil S.G., it was a little low, so I sparged another gallon of water through my grain bed, and got a gallon of 1.030 wort. By the time I was done boiling, my O.G. was 0.002 higher than expected. For some reason, for so many batches of AG, my O.G.'s were good, and I thought maybe I could get a batch of starter from the tail runnings. The first gallon of tail runnings was right at 1.030, so I added it to my BK. I added another gallon of water and got a 1.020 gravity reading, so I made starter with it. My first BIAB batch O.G. was a little low, so I added a "extra" gallon of sparge water, and it brought my numbers up to my predicted O.G. The time savings was huge compared to AG, so now I need to figure out how to improve my BIAB technique, to get better efficiency from the start.
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If you were expecting 1.085 and got only 1.044, I would look at a couple of areas.
First is your grind, making sure you are not too coarse and do not have a lot of uncrushed kernels. A simple inspection of the spent grains can answer this for you.
Second is your mixing of the grains into the water. If the grains are not fully dispersed and you get dough balls, the wetting of the outside grains will prevent water penetration into the center of the dough ball and keep the starches from being converted and extracted. Especially with the high grain loading of higher gravity brews this can become an issue. Mixing several minutes initially combined with stirring several times during the mash will help with breaking up any dough balls that may have formed.
First is your grind, making sure you are not too coarse and do not have a lot of uncrushed kernels. A simple inspection of the spent grains can answer this for you.
Second is your mixing of the grains into the water. If the grains are not fully dispersed and you get dough balls, the wetting of the outside grains will prevent water penetration into the center of the dough ball and keep the starches from being converted and extracted. Especially with the high grain loading of higher gravity brews this can become an issue. Mixing several minutes initially combined with stirring several times during the mash will help with breaking up any dough balls that may have formed.
copper2hopper
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I have same issues. Twice now! For my very first time brewing. Efficiency, pre boil gravity and post boil OG were all low. Got a 59% efficiency on my first and 69% on my second batch. Gravities were both 10 points under where they needed to be. Looks like I'll just be having "light" ABV versions of these recipes. Been researching and overall I think I will add in sparging, dunk sparging, double milling my grains (even though the turd at my LHBS told me not to), maybe increasing my grain amounts a little, mashing out, and stirring a lot through the 60 minute mash. These all should increase my efficiency and gravities.
Uugghhh, Copper that doesn't make me feel good. Have you read any about mashing longer, possibly instead of dunk sparging? Or adjusting mash temp?
You mentioned upping the grain amts...have you seen a formula for that? How much would you add?
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Uugghhh, Copper that doesn't make me feel good. Have you read any about mashing longer, possibly instead of dunk sparging? Or mash temp?
You mentioned upping the grain amts...have you seen a formula for that? How much would you add?
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You mentioned upping the grain amts...have you seen a formula for that? How much would you add?
Sent from my iPad using Home Brew
copper2hopper
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http://byo.com/stories/item/1375-skip-the-sparge
Long read and time consuming formula here but someone forwarded this to me and I crunched it out for a different recipe I'm gonna try. Great information though.
Long read and time consuming formula here but someone forwarded this to me and I crunched it out for a different recipe I'm gonna try. Great information though.
MindenMan
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For my BIAB "trial", my method wasn't the standard BIAB method; I used a "Zapap" tun to help. I heated my mash water, put my bag into my pot, added the grain, stirred like crazy, and walked away for an hour. I pulled out the bag, set it into my Zapap tun, added 4 gallons of strike water, stirred, covered, and 10 minutes later, drained and added to BK, along with the first running wort. I hit the predicted O.G., much to my surprise. The thing about the Zapap tun, is a five gallon bucket with a lot of small holes drilled in the bottom, placed inside of another 5 gallon bucket with a spigot, making a bucket with a false bottom. I saved over a hour of the time it usually takes after mashing, and a $4.00 one time investment to save an hour and a half every time I brew, was a no-brainer.
My first time I bought a Corona style mill since my local supplier didn't have a mill. Not knowing better, I set the mill tight as possible and got 80% no sparge. The next brew I tried a small sparge and upped my efficiency to 85% and the only time since that it has been lower is when the lock nut on the mill came loose and I got a little coarser crush. I've even quit using the hour long mash because I've found that with the fine milled grain the conversion is over in less than 10 minutes.
Until you have your own mill, you are at the mercy of the LHBS and their mill is set to avoid a stuck sparge, not high efficiency. High efficiency doesn't sell as much grain so there is little incentive to set the mill tighter. You can compensate somewhat for a poor crush by mashing longer but as the milling gets worse, the mash time gets really long. You can increase your efficiency a little by doing a "mash out" because sugar is more soluble in hotter water but the increase is so minimal it doesn't offset the cost of fuel to heat the mash.
copper2hopper
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Thanks! What about tannins and all that it keep reading about. Have you had any issues with that in any batches you have done? And how many have you done this way?
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You will increase the probability of extracting tannins if you have shredded or ground up the husks, and have high pH and have high temperatures. If you watch the pH and temperature closely, you should not have an issue with tannins from the grains.
To add to what RM-MN has said above, there are enough variables in brewing to control. Having your crush vary from one batch to the next will make it hard to determine if any changes you make to recipe or process has made a quality impact on your brewing. I use a corona style mill and have numbers similar to what RM-MN is getting for extraction efficiency. I do BIAB with batch sparge and heat my sparge water only to around 160F.
edit: Also, there are a lot of people who discourage squeezing the bag. Don't worry about it and squeeze away. As stated above, if your pH is in a good place (below 6.0) you will not have to worry about the tannins.
To add to what RM-MN has said above, there are enough variables in brewing to control. Having your crush vary from one batch to the next will make it hard to determine if any changes you make to recipe or process has made a quality impact on your brewing. I use a corona style mill and have numbers similar to what RM-MN is getting for extraction efficiency. I do BIAB with batch sparge and heat my sparge water only to around 160F.
edit: Also, there are a lot of people who discourage squeezing the bag. Don't worry about it and squeeze away. As stated above, if your pH is in a good place (below 6.0) you will not have to worry about the tannins.
ArkotRamathorn
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Another vote for the "grab that bag and give it a good squeeze" party. I usually give the bag a good little jangle, I don't squeeze it dry, but I do try and get a bit out of it, hard to describe.
Also another vote for the 'buy a grain mill' party. I bought a corona mill on Amazon recently, I think 25 or 30 bucks and built a little stand to attach it to. My first batch I didn't get *great* efficiency on, but I'm pretty positive it had more to do with that I was desperately trying to fit 15lbs of grain into a 7 gallon kettle with 4 gallons of water (seriously, that was a long ass day). If I had dunked it a bunch, and rinsed with maybe 3 more gallons of water, and then hit my volume properly after the boil, I would've been just fine. Next batch I used my mill on, loosened the grind up a tiny bit, did a half batch of another high gravity recipe (so instead of 13.5lbs of grain, 6.75lbsish), dunk sparged, rinsed with more sparge water, and hit approximately 76% efficiency.
Not sure how I'm gonna hit 80-85%. But I'm not gonna worry a ton about it, most o fthe time when I write my recipes down in my beer diary I'm writting the numbers down with calculated 75% efficiency.
braukaiser.com would be a good read - lots of info about efficiency, both conversion and lautering.
DurtyChemist
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Explain the brew day in extensive detail. What was the grain bill?what was your mash water volume? Temperature? Time? Did you pull the bag out and just get rid of it or did you wait for everything to drain out? Did you do a mash out? Did you monitor temperatures and if so how often? I'd say its more your process than your crush. Letting the mash go longer won't change anything if you remove potential sugars or have steps in your process that need to change.
