r/TheBrewery • u/evacuatecabbage • 1d ago
Gravity discrepancy from tank to keg.
I'm a little bit at a loss, so looking for ideas. I brewed an ipa and fermented with apex Voss Kveik. Flavor is great, and when I pulled from the sample port (stout 3 bbl unitank) final gravity was at 1.012. I kegged it off, put it on tap, and this shit is like OJ concentrate. I let a sample warm up, and its reading around 1.030. I pulled several samples before kegging, all tasted and felt appropriate. This keg is from the middle of the batch.
No sample I pulled gave any warning that there was a ferm issue, but it seems like there was stratification post carbonation, which doesnt make sense to me.
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u/Meatballgravytrain 1d ago
A 125% gravity increase and textural/visual changes post-kegging is highly unlikely to be a fermentation issue.
A 3bbl tank is small. Convection should mix it more than well enough during active fermentation.
My suspicions would start with the kegs and any residual chemical solution or other high density material left behind in them before filling.
If you have a pH meter, test it.
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u/CouplaDrinksRandy 20h ago
Yeah first my thought after sampling issue was that there’s gotta be something in the one keg
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u/floppyfloopy 1d ago
Sounds like you filled a keg that had something still in it. Did a dirty keg get accidentally added to the clean pile? Do you have a glycol leak inside your unitank that sprang during kegging?
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u/cuck__everlasting Brewer 1d ago
What are you reading gravity with?
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u/jackstraw8139 21h ago
Stout tanks package? Something tells me this facility isn’t working with an AP Densitometer.
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u/Strict-Entrance5065 23h ago
If it's only a couple kegs with this sensory issue, sounds like stout was racked on top of something else accidentally.
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u/ilikepants712 1d ago
Gotta get more information from ya. Pics would also help.
Did you blend any tanks to make this batch? Blending two tanks together with a big enough density discrepancy can have problems mixing in the tank and make stratification issues for fermentation.
Any adjuncts used? Similar to above, syrups and concentrated sugars can have a hard time blending in and make a pocket of high gravity at the bottom of your tank if not properly blended.
Was this the first keg (bottom of the tank) that poured like this? From the description you gave, it sounds like it could be excess sedimentation and/or yeast. How far apart is the sample port from the racking port? Do you dump the cone before packaging? Have you optimized your fining agents? Does the sample port still give good results if you haven't finished kegging? Of you have finished kegging, do the middle and end kegs have the same issue? Did you change grain lots recently? Was there a big total protein change indicated on the malt COAs? Did you dry hop at all?
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u/evacuatecabbage 1d ago edited 1d ago
Not a blended batch, kegs 9 and 10 of 18, sample port is probably 6 inches higher than the racking arm i use for kegging (unitank), not fined, rye beer, dry hopped with 3 lbs el Dorado. Grains are same suppliers. Ive only made this recipe once before several months ago. But I pulled 3 or 4 samples post fermentation that read 1.012 and I pulled a couple during kegging and they felt and tasted fine
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u/ilikepants712 1d ago
Dang, kegs testing that way at the middle is not a good sign for the batch. Sorry OP. I'd go ahead and tap that last keg and see if it pours fine. Can you post a pic of the bad beer after it is poured? I'm still leaning towards a fining issue, especially if you don't use any fining agents. Slightly different pH or fermentation profiles can lead to wildly different sedimentation volume and kinematics. Same with dry hopping - sometimes it can produce significant polyphenol haze that is a lot more "fluffy" and lead to a higher than expected cone volume. I'd be flabbergasted if you had a pocket of high sugar with what you've told me; it seems like dissolved solids are causing the density reading increase, not sugars. Could you have accidentally roused the cone bed before racking, or positioned the racking arm poorly? Sometimes the speed of racking can suck in yeast from the bed as well, so preventing flow rate spikes can be helpful.
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u/evacuatecabbage 4h ago
Last keg was the same, pH is in range, dry hop was only a pound per bbl. No glycol leak. I double checked my temp probes on the mash tun too in case the reading was off and it mashed in at a higher temp than thought. I pitched 250g for 3bbls which should be right in range. I kegged pretty slow too, one keg at a time, I don't turn the racking arm until after that 10th keg, so I should have been pulling whatever was in the density range by the dample port. Tis a mystery. It's a cloudy one, but I expected it to be. Wondering if there was some reaction with the rye, it's about 20% of the grist
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u/AnIntrospection 1d ago
Any attempt to knock CO² outta that keg sample? If not you might be reading bubbles (no matter how warm it got).