First AG overshoot.

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beergee

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Hey guys, did my first BIAB all grain recipe this morning and overshot my target OG by about 10 points.
I also ended up with less volume in the no chill cube.
Can I dilute when putting into the fermenter to bring down the OG and increase the volume?
My target was 23L and 1.060, I ended up with 20L and 1.070.
Probably due to my mash temp being a couple of degrees too high and the fact its new equipment so I don't know its ins and outs.
Is there a calculator out there to work this out?
Any help would be great.
Cheers.
 
Hi beergee. You can do a couple of things.
Yes, you can boil and cool some water and add to fermenter. You can wait until the beer has fermented and add some boiled, cooled water. Or you can leave it as is and adjust your brewing for next time you BIAB. For mine, I would leave it as is.
I doubt that mash temp had anything to do with it being over gravity. It was most likely the mill crush or your volumes are incorrect, hence being under volume in the cube. Oh, and you have new equipment, that's another variable. Which software are you using?
Fun hobby, aint it?
 
Hi beergee. You can do a couple of things.
Yes, you can boil and cool some water and add to fermenter. You can wait until the beer has fermented and add some boiled, cooled water. Or you can leave it as is and adjust your brewing for next time you BIAB. For mine, I would leave it as is.
I doubt that mash temp had anything to do with it being over gravity. It was most likely the mill crush or your volumes are incorrect, hence being under volume in the cube. Oh, and you have new equipment, that's another variable. Which software are you using?
Fun hobby, aint it?
Thanks for answering @razz , it was a pre-packaged recipe from my LHB shop.
Thought I'd go for something easy to start with not knowing my dead space, boil off rates etc.
20201003_190829.jpg
 
Every brewer should know C1V1=C2V2
Where C is a condition (in this case SG)
And V is a Quantity in this case Liters

You have 20L (V1) of wort at 1.070 (C1), to see how many liters at 1.060 (C2) just put what you have into the equation, then rearrange to tell you the answer. Just remember that SG is nonunitary, it isn't a number its a comparison to the weight of water so use points (1.070 is 70 points)
20*70=X*60
(20*70)/60=23.333L
Means you came dam close to hitting your target, just need to make that 3.333L adjustment, or cop the stronger beer.
Mark
 
Every brewer should know C1V1=C2V2
Where C is a condition (in this case SG)
And V is a Quantity in this case Liters

You have 20L (V1) of wort at 1.070 (C1), to see how many liters at 1.060 (C2) just put what you have into the equation, then rearrange to tell you the answer. Just remember that SG is nonunitary, it isn't a number its a comparison to the weight of water so use points (1.070 is 70 points)
20*70=X*60
(20*70)/60=23.333L
Means you came dam close to hitting your target, just need to make that 3.333L adjustment, or cop the stronger beer.
Mark

Great thanks @MHB , simple algebra! You make it sound much less complicated.

1.070 is pretty high, I'm assuming my 1x 11g packet of BRY97 will struggle to ferment it?

I do have some US05 I could throw in?
 
Yeast pitching is based on three variables, Volume, Target number for the yeast in question and wort gravity.
It is usually expressed in the form
Cells required = V(in mL)*target*oP, (oP - Plato being the other way to measure SG, (SG=(4*oP)/1000+1 roughly)
Target is usually 0.5 - 1 million cells/mill/oP, for ale. For Lager you need about 1.5 times as much. There is a fair amount of latitude in the outcomes but as a general rule the higher the gravity and the colder you are fermenting the more yeast you need to get a quick clean ferment.
If we looked at the middle of the Ale range 0.75EXP6 cells /mL / oP (1.070 is ~17.5oP)
Cells needed is = 20,000*0.75EXO6*17.5 = 262,500,000,000 or 2.625EXP11.
A quick Google says the yeast has 5EXP9 cells per gram. 2.625EXP11/5EXP9 = 52.9g
So yep, suspect 11g might be a bit on the light side.

That said the Spec sheet says 50-100g/hL (100L) so even at the high end 100g/hL you would only be looking at 20g in 20L.
Frankly something isn't adding up, have to have a better look at their recommendations. Maybe they are referring to what will be there at the end of the reproductive stage...
Lets just say somewhere between 2-4, 11g packets will be fine, 1 I suspect is asking for trouble.
Mark
 
if it was me i'd dilute to get your 1.060 just so you have a baseline for the end result.
Yeah, I'm leaning that way. I've already boiled some filtered water in preparation.
Hoping to get it in the All Rounder tonight.
 
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