WTFermentation?

[pearlbeer]

Need help. I can't figure this one out.

13 days ago I brewed an IPA. Mashed at 149. All grain. OG 1.061. Pretty standard recipe.

Made a starter using WLP001. Oxygenated the wort for about an hour using a airstone.

Pitched, fermented at 66, ramped up to 68 over 4 days in a controlled chest.

Fermentation began within hours, and was rigorous within 24hrs.

FG should be 1.010.

Sample pulled at day 9, day 14. 1.021. Fermentation appears complete, although the beer is pretty cloudy, indicating that yeast are still in suspension, but not working. I gave the carboy a good shake at day 11 to try to rouse the yeast. Does not appear to be working. WTF? I'll try tonight to pitch another tube of WLP001, i guess.

These are not problems:
Grain bill was correct
Mash temp was not high
Although beer is cloudy, I dont taste any sign of infection
Hydrometer is calibrated, and I can taste the sweetness in the beer

am I missing something? Typically WLP001 ferments out for me in a week. I'm happy to let it sit longer, it just seems that 1.021...it has a long way to go.

 

[COLObrewer]

I'm stuck too, what was the grain bill?
Did you aerate using pure oxygen or ambient?

 

[boostsr20]

If time doesn't heal it maybe throw in some simple sugar like honey to get them active again and see where that takes it.

 

[pearlbeer]

I'm stuck too, what was the grain bill?
Did you aerate using pure oxygen or ambient?

Ambient
Standard gain bill. Mostly Pale Malt.

 

[Seven]

OG 1.061, FG 1.021 = 64.2% apparent attenuation

How To Brew states that most yeast strains attenuate in the range of 65 - 80%.

Does WLP001 normally attenuate higher than this? If yes, maybe you got an old or bad batch of yeast?

 

[flabyboy]

I have read that yeast can drop out if they have too much O2 to work with. During open fermentation the yeast need to be roused up from the bottom to finish off. Have you tried gently rousing the yeast?

 

[jmo88]

Sounds like you did many things correctly and you know what you're doing. If it were me, I'd ramp the temp above 70F. It won't hurt it any at this point. Most, if not all, yeast flavors have contributed at this point. Although, I can get 77% attenuation out of a typical ipa grain bill fermented at 58F with wlp001.

How old was the yeast and what size was the starter and how long did you let it go? Fresh vial or washed/cropped?

ALSO, perhaps your thermometer you used for the mash reads low. Has it been calibrated recently?

 

[pearlbeer]

Sounds like you did many things correctly and you know what you're doing. If it were me, I'd ramp the temp above 70F. It won't hurt it any at this point. Most, if not all, yeast flavors have contributed at this point. Although, I can get 77% attenuation out of a typical ipa grain bill fermented at 58F with wlp001.

How old was the yeast and what size was the starter and how long did you let it go? Fresh vial or washed/cropped?

ALSO, perhaps your thermometer you used for the mash reads low. Has it been calibrated recently?

Let's see. Fresh Vial. Pitched about 1.4L Starter grown up over about 20hrs.

I was mashing in a HERMS system, with an inflow and out flow temperature gauge and a gauge in the vessel than contained the heat exchange water. So unless all three termometers are jacked, I think I am measuring correctly.

 

[jmo88]

Let's see. Fresh Vial. Pitched about 1.4L Starter grown up over about 20hrs.

I was mashing in a HERMS system, with an inflow and out flow temperature gauge and a gauge in the vessel than contained the heat exchange water. So unless all three termometers are jacked, I think I am measuring correctly.

A mystery. How do you feel about brett?

 

[Salmonhouse]

I'm having similar problems with the last couple batches. I used liquid ale yeast and starters but they stopped short of 1.020, started at 1.06+ Not sure what went on with mine. I have since repitched some nottingham from a starter and that has worked on a couple of my carboys. Now i'm trying the pitch on an old yeast cake technique and seeing some activity on the airlock, ramped the temps up to like 73 F.

 

[motobrewer]

OG 1.061, FG 1.021 = 64.2% apparent attenuation

How To Brew states that most yeast strains attenuate in the range of 65 - 80%.

Does WLP001 normally attenuate higher than this? If yes, maybe you got an old or bad batch of yeast?

mashed at 149 (and using an average-crystal grainbill, which he seems reluctant to give) WLP001 should take it down to 1.010 at highest. my 1.055 IPA mashed at 149 got down to 1.006 using us-05, fermented at 65F. does seem like a lot of O2

if it's still cloudy i'd say leave it alone for another week. pitch another vial if you want, or a pack of us-05.

 

[jmo88]

Too much O2? Damage to yeast cells? Here is a great thread with several links:

https://www.homebrewtalk.com/f13/question-about-oxygenating-your-wort-50663/

 

[motobrewer]

from wyeast's site:

Aquarium Pump w/ stone 8 ppm 5 min

http://www.wyeastlab.com/hb_oxygenation.cfm

you hit it with an airstone for an hour? might be your problem. i'd repitch. seems like there's conflicting theories on over-oxying

 

[cheezydemon3]

Seriously, AN HOUR?? I'll "WTF" oxygenating for an hour.