Brewers Friend Help

[Rogue_Atom87]

So I decided to try and move away from extract and try BIAB. I purchased a bag and hop sack online yesterday and should be here in about a week when pumpkin ale is finished fermenting. I wanted to do Fruit Bazooka recipe found on northern brewer but for 2.5 gallon. I decided to input everything into brewers friend just to get a feel for it and the numbers are way off from what northern brewer has.

https://www.northernbrewer.com/products/fruit-bazooka-ipa-all-grain-beer-recipe-kit
I halved all the ingredients and showing OG of 1.071 and ABV of 8.06% when its supposed to be 1.064 and 6.7%. Also IBU are at 37.14 instead of 50. One thing may be factor here is selection I have. recipe calls for hops to be added right after flame out. What is this called? Mash, Aroma Whirlpool, or hopback. I selected whirlpool and that is what 37.14 is based off of.

Equipment profile setup with following:
evap rate at 3 quarts/hr
grain absorption .4 quart/lb
kettle loss 1.25 qt
general loss 1qt
efficiency 72%
mash thickness 1.5qt/lb
28 qt kettle size

I ran calc on boil size and shows pre at 4.08 and after 3.33. This is .75 gallon over batch size I want. I am assuming this doesnt calculate grain aborption?

 

[3 Dawg Night]

BF has several choices for ABV/IBU/SRM that may differ from what NB uses.

For flameout additions, I just put it in as 0 min of the boil. Playing around with it, it looks like there's no difference between 0 min boil and whirlpool as far as IBU's are concerned.

BF calculates grain absorption. If you have batch size, grain, hops, and boil time entered, it should calculate a post-boil volume that will give you the desired batch size into the fermenter, after accounting for kettle deadspace, misc losses, etc. It's always worked out pretty well for me.

 

[BrewnWKopperKat]

showing OG of 1.071 and ABV of 8.06% when its supposed to be 1.064 and 6.7%.

Specific to OG estimates, what efficiency does NB assume for their recipe? Also, what volume of wort are they targeting for the fermenter? If this information is not in the recipe, then one may have to apply some educated guesses to get the same numbers in Brewers Friend.

 

[Rogue_Atom87]

Not sure on NB Efficiency. Sounds like most efficiencies for BIAB are 72-80%. Should I adjust the grain bill so brewers friend calculates 1.064 ABV?

Also regarding calculations I want 2.5 gallon in fermenter. Doing calculations I get the following

Fermenter - 10qts
Grain absorption - (.4*6.75lb)= 2.7QT
Evap Rate - 3qts for 1 hour boil
Kettle Loss - 1.25QT (area below spigot)
Misc - .5QT ( I adjusted down)

This give a total volume before starting at 17.5Qts or 4.36 Gallon. Post Boil and grain removal I estimate it to be 11.25QT which is fermenter volume and trub below spigot.

Brewers friends give me a pre and post boil volume of 3.95 and 3.2. Based on the above it should be 4.36 and 2.8. Did I mess up the calculations?

 

[3 Dawg Night]

BF also includes a 4% volume shrinkage from boiling to pitching. That gets you to ~3 gal. Then, I think there's about 1/2 gal of trub losses baked in.

Here's how BF explains their calcs.

 

[rsquared]

Not sure on NB Efficiency. Sounds like most efficiencies for BIAB are 72-80%. Should I adjust the grain bill so brewers friend calculates 1.064 ABV?

Also regarding calculations I want 2.5 gallon in fermenter. Doing calculations I get the following

Fermenter - 10qts
Grain absorption - (.4*6.75lb)= 2.7QT
Evap Rate - 3qts for 1 hour boil
Kettle Loss - 1.25QT (area below spigot)
Misc - .5QT ( I adjusted down)

This give a total volume before starting at 17.5Qts or 4.36 Gallon. Post Boil and grain removal I estimate it to be 11.25QT which is fermenter volume and trub below spigot.

Brewers friends give me a pre and post boil volume of 3.95 and 3.2. Based on the above it should be 4.36 and 2.8. Did I mess up the calculations?

Pre boil is kettle volume after mashing, so the 2.7 grain absorbtion is not included. Based on your numbers above, I would come to 3.69 gallons pre boil. Then you have to account for about a 4% volume increase due to temperature (i.e. 1qt at room temp takes up 1.04 qt at 212 F). Taking that into account, I'd expect a 3.84 gallon pre boil, which is pretty close to the BF number. There's perhaps some small loss not listed above, but the numbers make sense to me. Also, if we assume BF got the 3.95 pre boil correct, the 3.2 post boils exactly account for the 3qt boil off rate. This again is a hot (immediately at the end of boil) temp, so divide by 1.04, and you get 3.08 gallons after chilling.

 

[Rogue_Atom87]

Uploaded everything into Brewfather and for me like layout better. Showing 4.21 mash volume and 3.61 pre boil. With losses this equates to 2.75 gal post boil. .25gal sits below spigot so there is my 2.5 gallon. Only adjustment made was NB recipe cut in half would call for 5.25Lb of Pilsner malt. The recipe below I have 4.75lb