Extract OG way lower than target

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

BiddoBrasserie

Brasserie de Laurier
Joined
Jun 19, 2020
Messages
17
Reaction score
9
Location
Biddeford
This may be posted elsewhere, however my searches lead me only to kits. I’ve been brewing AG for a few years but time has been short so today I brewed my first extract. I ran the number through Brewfather and brewed a 3gal Quad. The Target was 1.097 but I was way under at 1.078. Here’s my recipe.

3.9gallons distilled H2O, 60min boil
7.5# Briess Light LME
1# D-180
6oz Special-B steeped 30mins

2oz of saaz @ 60
1oz Styrian Goldings @ 15

Omega OYL-028 Westmalle strain

Any pointers would be awesome, would love to try more extract brews due to time restraint. Thanks!
 
3 gallons exactly. In the pot maybe .5 gallon. This is using my Brewfather profile. I should also note, 10.5 anvil foundry 120v.
 
With around 0.5 gal left in the kettle, your end of boil volume was around 3.5 gal (not 3 gal). And the wort OG will be lower. Here's an example using just the LME:
  • 7.5 lb LME * 36 PPG = 270 gravity points
  • in 3.0 gal: 270 / 3.0 is OG 90
  • in 3.5 gal: 270 / 3.5 is OG 77
 
3 gallons exactly. In the pot maybe .5 gallon. This is using my Brewfather profile. I should also note, 10.5 anvil foundry 120v.

With around 0.5 gal left in the kettle, your end of boil volume was around 3.5 gal (not 3 gal). And the wort OG will be lower. Here's an example using just the LME:
  • 7.5 lb LME * 36 PPG = 270 gravity points
  • in 3.0 gal: 270 / 3.0 is OG 90
  • in 3.5 gal: 270 / 3.5 is OG 77
I just measured the wort left in my kettle and it was just shy of 1 gallon not .5. So that makes sense. How would I calculate this in Brewfather?
 
With around 0.5 gal left in the kettle, your end of boil volume was around 3.5 gal (not 3 gal). And the wort OG will be lower. Here's an example using just the LME:
  • 7.5 lb LME * 36 PPG = 270 gravity points
  • in 3.0 gal: 270 / 3.0 is OG 90
  • in 3.5 gal: 270 / 3.5 is OG 77
Op also used one pound of candi syrup. That’s 32ppg, divided by 3.5 and you have an extra 9 points. So in total, OG of 1.086.

That’s close to what op was expecting. The lower measured OG could be measurement error, stratification, or volume misreading. Or all three.
 
I just measured the wort left in my kettle and it was just shy of 1 gallon not .5. So that makes sense. How would I calculate this in Brewfather?
A gallon of leftover wort/trub is a lot in a 3 gallon batch (it's 25%)!
You can probably recover most of that (high gravity) wort by letting it sit in a tall beaker or jug, then decant the liquid, leaving the trub. Or straining through a tight mesh nylon bag placed in a funnel. I often do that, reclaiming 2-3 quarts per brew.

[rephrased]
Re-pasteurize the reclaimed wort by heating to 160-170F in a kitchen pot. Put a lid on and leave it at that temp for 10-20'. Then chill and add to your batch.

Especially when dealing with high(er) gravity brews, wort reclamation pays off.
 
Last edited:
The lower measured OG could be measurement error, stratification, or volume misreading. Or all three.

Agreed. It could be any of those. But also ...

In reply #3 and #5, it was mentioned that there was wort left behind.

Here is better gravity points estimate [1]:

1670541209958.png
[1]​
In 3 gal of wort, 291 GPs are OG 97. This matches target OG in reply #1.
In reply #1, a measured OG of 78 was mentioned. 291 (GPs) / 78 (OG) = 3.73 gal of wort at end of boil.

See #3 and #5 for the approximate amount of wort that was left behind.



[1] the PPG numbers may not be exactly what BrewFather uses.
 
Agreed. It could be any of those. But also ...

In reply #3 and #5, it was mentioned that there was wort left behind.

Here is better gravity points estimate [1]:

In 3 gal of wort, 291 GPs are OG 97. This matches target OG in reply #1.
In reply #1, a measured OG of 78 was mentioned. 291 (GPs) / 78 (OG) = 3.73 gal of wort at end of boil.

See #3 and #5 for the approximate amount of wort that was left behind.



[1] the PPG numbers may not be exactly what BrewFather uses.

Right. In Brewfather for 4 gallons (to account for boil off, trub/chill, etc) 7.5# of LME and 1# of D-180, and I suppose the minimal 6oz of special b was going to give a target of 1.097. In my calculations I’m around 2.5# of fermentables shy. Weird.
 
@BrewnWKopperKat I was adding to your calculations and just wanted to account for all the fermentable. Your table does that and shows the math pretty clearly.

@BiddoBrasserie it looks like you simply ended up with more liquid. You essentially diluted your wort by a considerable amount. That accounts for the lower gravity.
 
You can edit the equipment profile in that recipe and change the "Trub/Chiller Loss" to 1 gallon.
I just did this and the gravity fell right around where I ended up. I then used calculations above and arrived at the TG I was hoping for. 1 gallon of trub loss seems like a ton compared to my AG brews but oh well. Thanks for everyone’s help.
 
Was it actual loss or more like leftover? That will change how you build your profile.

Also, 1 pound of DME displaces about 9.4 oz of water. LME displaces about 10.6.

So at 7.5 pounds plus candi syrup you probably had half gallon extra volume.
 
Was it actual loss or more like leftover? That will change how you build your profile.

Also, 1 pound of DME displaces about 9.4 oz of water. LME displaces about 10.6.

So at 7.5 pounds plus candi syrup you probably had half gallon extra volume.
That’s a good question. I’d say there was around .5-.7 gallons of cold break with the remainder residual wort. With the LME I was wondering how it was going to affect the final volume. I guess I could calculate that into my losses.
 
I’m not sure I’d calculate it as a loss. Its actually a gain. You’re getting more volume by adding extract. Brewfather might already factor this in. I’m not sure.
 
1 gallon of trub loss seems like a ton compared to my AG brews but oh well.
WIth a 3 gal batch, it's doubtful that you had 1 gal of trub.



I only brew with DME and see very little displacement (as DME contains very little water).

IIRC, LME can have a measurable impact on initial wort volume.

For displacement values for DME & LME, maybe @VikeMan can help.
 
WIth a 3 gal batch, it's doubtful that you had 1 gal of trub.



I only brew with DME and see very little displacement (as DME contains very little water).

IIRC, LME can have a measurable impact on initial wort volume.

For displacement values for DME & LME, maybe @VikeMan can help.

Default values in BrewCipher for "Dissolved Gallons per Pound" are...

DME: 0.064339
LME: 0.08475

These numbers were obtained by measurement many years ago. They contain more sigificant digits than warranted, but that's how I roll. They seem to work okay for BrewCipher users, in that nobody has ever told me that they experience something different.

If 0.064 dissolved gallons per pound sounds high-ish for DME, compare to Sucrose at 0.074 gallons per pound. I didn't measure sucrose, but it can be derived via some brix/SG definition gymnastics. I can post if anyone cares.
 
You can edit the equipment profile in that recipe and change the "Trub/Chiller Loss" to 1 gallon.
You can also put that gallon into a 2 gallon container, add a little yeast and an airlock and see what you get for beer when all that trub has settled. Bottle up this little bit and see how its clarity compares to the rest of the batch.
 
You can also put that gallon into a 2 gallon container, add a little yeast and an airlock and see what you get for beer when all that trub has settled. Bottle up this little bit and see how its clarity compares to the rest of the batch.
Generally I try to get as much wort into the fermenter as possible. I might use a fine mesh strainer to limit hop material, but as long as the trub level is below the spout on my fermonster I am fine with it in there.

Fermenting the kettle trub, or making a second runnings batch (if doing all grain) are great ways to use saved yeast slurry from previous batches.
 
WIth a 3 gal batch, it's doubtful that you had 1 gal of trub.



I only brew with DME and see very little displacement (as DME contains very little water).

IIRC, LME can have a measurable impact on initial wort volume.

For displacement values for DME & LME, maybe @VikeMan can help.

I’m a bit confused.
WIth a 3 gal batch, it's doubtful that you had 1 gal of trub.



I only brew with DME and see very little displacement (as DME contains very little water).

IIRC, LME can have a measurable impact on initial wort volume.

For displacement values for DME & LME, maybe @VikeMan can help.

I’m a bit confused or just extremely slow so please forgive me. I used 4 gallons of water (distilled, 4x1gal jugs) and placed 7.5# LME (1.5# jug and a 6# jug) in the kettle along with 1# of D-180. When calculated under the Anvil Foundry 10.5 120v profile in Brewfather, the yield was 1.097. Which is where I calculated .95gal of trub/chill loss (LME+D-180 displaces 10.6oz of water/lbs, 8.5x10.6=90.1 oz which is .70 which I added to my existing .25 gallon trub/chill loss from AG batches.) When I accounted for the loss, or what was in the kettle, BF recalculated the OG of 1.077, which was right around what I ended up with. If this wasn’t a loss, or trub, why was it calculated as such?
 
If this wasn’t a loss, or trub, why was it calculated as such?
It may be that I'm thinking of 1) trub and 2) "wort left behind" as two separate things. For me this is useful, as I can adjust my starting boil volume to eliminate "wort left behind". Note that my brewing equipment has very little "dead space".

The Target was 1.097 but I was way under at 1.078.
If you were aiming for 3 gal of OG 97 wort in the fermenter and have 0.5 gal of 'dead space', you need to create a 3.5 gal OG 97 wort at the end of the boil.
 
Last edited:
Back
Top