Fermentation stuck at 1.022?

[Ntense]

Hi guys,
I brewed 18 days ago 12 gallons of Bitburger, using White Labs WLP830 yeast.

OG was 1.050 and now it's stuck at 1.022 (Temp: 48F). Doesn't seem to ferment anymore..

I know I underpitched for this batch ( 4 packs of yeast instead of 8)... maybe it's why?

The beer taste very good and it's not sweet at all.

Any idea?

By the way, I'm also fermenting another lager right now (27 gallons of Munich Helles at 53 F) with the correct pitch of yeast and this batch is fermenting well.

let me know,

David

 

[kh54s10]

1.022 sounds really high. But I would expect it to be sickly sweet, so if it tastes good, I would just ignore the FG reading. The underpitch may have made it stop short??

Or take another reading with the temperature of the sample at the calibration of the hydrometer. Make sure there are no co2 bubbles that would float the hydrometer giving an inaccurate reading.

 

[JimRausch]

Caveat- I haven't used WLP830, but when I do my lagers, I raise the temp to mid 60'sF toward the end of fermentation(usually 7days or so). Call it a D-rest, but essentially it keeps the yeast active. Then I do expect a point or two of further attenuation during the lagering process.
So, I think it's perhaps overtime to raise the temp on your Bitburger. Good luck!

 

[Ntense]

thanks guys!

I'm using a refractometer for the samplings gravity, by the way.

But I think you are right, I'll raise the temperature to mid-60'sF...

thanks again!

 

[Yooper]

thanks guys!

I'm using a refractometer for the samplings gravity, by the way.

But I think you are right, I'll raise the temperature to mid-60'sF...

thanks again!

That's why your reading is so high- refractometers read the refraction of light through a sugar solution, and alcohol skews that reading.

Take a hydrometer reading, and you'll see that the reading is much lower.

There are calculators online that correct for the alcohol in the mix, but they are not always 100% accurate. They work for a guestimate though. This is the best one I've found: http://seanterrill.com/2012/01/06/refractometer-calculator/

 

[kh54s10]

thanks guys!

I'm using a refractometer for the samplings gravity, by the way.

But I think you are right, I'll raise the temperature to mid-60'sF...

thanks again!

Did you calculate for the presence of alcohol? A refractometer is inaccurate when there is alcohol.

If not your true FG is about 1.004!!!!

 

[Ntense]

hahaha!! Thanks for the information!

I ordered the refractometer about 2 weeks ago... I thought I could use it also with alcohol, like with an hydrometer...

I'm going down right now to check gravity with my hydrometer!

That's probably why the beer tasted good and not sweet this morning!

 

[Ntense]

you were right! FG is much much lower with my hydrometer !

Problem solved!

thanks!