OG too high, can I add water? (BIAB)

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Semicole

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On pretty much all of my batches I've been going off of the recipe boil size when I start my mash, so if the recipe says boil size is 7.5 gallons that's what I put in my kettle when I start to heat the water for the mash. Pretty much all 3 or 4 batches I've done so far have resulted in lower than expected amounts of beer, usually between 4 and 5 gallons with this most recent batch resulting in just under 4 gallons.

So my first question is, am I doing that right? Or should I make sure there are 7.5 (or whatever the recipe boil size states) gallons of water/wort in the kettle before I start my boil?

On my most recent batch I ended with under 4 gallons of wort and my OG is at 1.088 for a recipe that has an expected OG of 1.065. I chilled it to around 90F, but it got too late, so I put it in the fermenter and sealed it and put it in my fermentation chamber overnight to let it cool the rest of the way down before pitching the yeast tomorrow morning.

My second question is, should I top off the wort in the fermenter to get my expected OG of 1.065 before pitching the yeast? Is there a calculator for that? How do I about this problem on the future? I'm assuming it's from me not doing the initial boil size correctly.

Thanks in advance!
 

roboto65

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Well I am by no means an expert but there are a lot of factors that contribute to your boil off. Like humidity,wind or lack of probably more than that again no expert, heck last brew I did was a gallon batch mine was thick when it finished an hour boil.
To answer your other question I added water to mine and I would think in my personal opinion that's fine mine was high also I added water.
 

beermanpete

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I suspect most of your shortage is due to absorption in the grain. You can add water as needed before starting the boil to adjust the volume and/or specific gravity. The boil gravity will be lower than the specified OG in the recipe. During the boil water is lost due to evaporation and the specific gravity will rise. At the end of the boil the specific gravity can be adjusted as well but it is better to do it before the boil to make sure the hop utilization is correct.
 

Miraculix

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Just add bottled water afterwards till you reach the desired og, no problems at all.
 

PADave

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On pretty much all of my batches I've been going off of the recipe boil size when I start my mash, so if the recipe says boil size is 7.5 gallons that's what I put in my kettle when I start to heat the water for the mash. Pretty much all 3 or 4 batches I've done so far have resulted in lower than expected amounts of beer, usually between 4 and 5 gallons with this most recent batch resulting in just under 4 gallons.

So my first question is, am I doing that right? Or should I make sure there are 7.5 (or whatever the recipe boil size states) gallons of water/wort in the kettle before I start my boil?

On my most recent batch I ended with under 4 gallons of wort and my OG is at 1.088 for a recipe that has an expected OG of 1.065. I chilled it to around 90F, but it got too late, so I put it in the fermenter and sealed it and put it in my fermentation chamber overnight to let it cool the rest of the way down before pitching the yeast tomorrow morning.

My second question is, should I top off the wort in the fermenter to get my expected OG of 1.065 before pitching the yeast? Is there a calculator for that? How do I about this problem on the future? I'm assuming it's from me not doing the initial boil size correctly.

Thanks in advance!
You need to work backwards. First figure out how much you want to end up with int the fermenter. I go for 5.5 gallon. Then add your kettle losses, boil off loss, and grain absorption loss. Only way to do this is to take accurate measurements as you brew and "dial in" your system. Calculators are only as good as the data that you put into them. I like using Brewers Friend, but there are several others. Once you get things set for your system, each brew will take a different amount of water, mainly based on the grain amount, and how much is absorbed.
 
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Semicole

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You need to work backwards. First figure out how much you want to end up with int the fermenter. I go for 5.5 gallon. Then add your kettle losses, boil off loss, and grain absorption loss. Only way to do this is to take accurate measurements as you brew and "dial in" your system. Calculators are only as good as the data that you put into them. I like using Brewers Friend, but there are several others. Once you get things set for your system, each brew will take a different amount of water, mainly based on the grain amount, and how much is absorbed.
That's something I haven't done yet, I made sure to note the amount of water I started with on this last batch and the amount of wort I ended up with, but I didn't take note of my losses as I went through each step - I need to make sure and do that next time, so I know going forward.
 

Morrey

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You are probably already more aware of "working backwards" than you may think. You have started with 7.5G and ending up short by around a gallon on a consistent basis. That big beer where the volume went under 4G is probably due to absorption with a fairly big grain bill in relationship to the other grain bills where you are coming in between 4 and 5 G.

Couple of ways I approach this with BIAB...I start with at least 8G of strike water, so that puts you .5G ahead of the loss curve already. I only go with 8G since my grains will overfill my 10G boil kettle otherwise. If your kettle can accommodate 8.5G of strike water you are home free. Make final adjustments at the end with bottled water.

If your kettle cannot accommodate any more water (like mine), I will pull the grain bag (after mashing) and slowly pour 1/2 G of warm water over the grain bag. This rinse sparge will help reclaim some of the sugars still in the grain bag, plus of course it adds back the volume you'll need later on to make up the desired volume you want into fermenter. **Final adjustments can be made with bottled water as you move the wort into fermenter making allowances for yeast cake and trub losses at the end of fermentation.

**Ideally you'll want to have the proper volume in the kettle (Pre-boil) and not at the very end, but if you have missed your volumes, this is your last resort.
 
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zymsmith

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If you use say 10 lbs of grain, that bag is gonna be hard to lift even after sparge/drain. All that added weight is water. Using 7.5G total water won't ever get 5 G to the fermenter. I almost always have to add water, usually at sparge since it will be pasturized. After cooling wort I'd stick with chilled preboiled water or properly steeped darks.
 

balrog

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I typically start with 7Gal strike, no sparge, no squeeze, BIAB, between 9-11# grain in a 10G kettle. I typically have 5-5.25G into fermenter but I also pour EVERYTHING into fermenter, no trub loss in BKettle. I have a boil off of 1gal/hr, rolling boil not insane volcanic boil.

You have to work out your numbers. Strike volume, sparge volume if used, start boil volume (helps you determine grain absorption volume and will be altered by squeezing or dripping), end boil volume, fermenter volume (which you have).
 

PADave

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If you use say 10 lbs of grain, that bag is gonna be hard to lift even after sparge/drain. All that added weight is water. Using 7.5G total water won't ever get 5 G to the fermenter. I almost always have to add water, usually at sparge since it will be pasturized. After cooling wort I'd stick with chilled preboiled water or properly steeped darks.
Not true at all. I rarely use over 7.5 gallon, do no sparge, full volume mashes and always get 5.5 gallon in the fermenter.
 

Morrey

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If you use say 10 lbs of grain, that bag is gonna be hard to lift even after sparge/drain. All that added weight is water. Using 7.5G total water won't ever get 5 G to the fermenter. I almost always have to add water, usually at sparge since it will be pasturized. After cooling wort I'd stick with chilled preboiled water or properly steeped darks.

Do you have some sort of lifting hoist or other type of system to help you bring the bag up out of the wort?
 
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