When to know if yeast is stalling

[hilljack13]

Other than the obvious....

Pitched two packs of S05 on 1.094OG ~4pm Sunday. SG was 1.076 as of last night, not bad I thought. Now I'm only down to 1.074 after 24 hrs. Using PRV and there is still activity, but not much. Wasn't any until pressure rose. Sitting at 12 PSI. I have a feeling this one is starting to stall early. Anything I can do besides wait?

Edit: Temp is 66F

 

[IslandLizard]

1.074 reading from a hydrometer?

Why start spunding this early?
Dissolved CO2 slows down yeast activity, so does pressure.

 

[hilljack13]

Tilt...I know not 100% accurate, but when I calibrate from hydrometer refractometer OG I am very close. I have read where pressure fermentation speeds up, not slows down. I guess I need to find a reference on that. This morning was at 1.072. It's moving, just slower than what I have seen with S05.

I need to learn to be more patient.

 

[jdauria]

Using Brewers Friend Yeast Calculator, a 1.094 gravity beer, assuming 5 gallon batch, would need almost 3 packs of dry yeast at the minimum pitch rate for an ale. Not sure if that would be different for pressurized ferment.

 

[mac_1103]

Using Brewers Friend Yeast Calculator, a 1.094 gravity beer, assuming 5 gallon batch, would need almost 3 packs of dry yeast at the minimum pitch rate for an ale.

This also assumes the minimum cell count of 6B/gram in the manufacturers' specifications, which is an underestimate by definition. Problem is that it's very hard to know how much of an underestimate. OTOH you probably shouldn't use the minimum pitch rate for a high gravity wort like this, and you would need 4 packs if you assumed 10B/gram and wanted to pitch 1M/ml/P.

 

[hilljack13]

Maybe I'll add more. I did drop the pressure to 10 PSI and raised temp one degree to 67, dropped 4 points during the past few hours.

When would it be too late to pitch more?

 

[Bramling Cross]

TILTS are great, I love both of mine and wouldn't trade them for the world. Nevertheless, they can be a squirrely, especially on large, vigorous fermentations at high krausen. You currently appear to match those criteria.

Personally, I kinda think of high krausen with my TILTS as being that uncomfortable period during a spaceship's re-entry when ionization around the spacecraft makes contact with mission control impossible. Granted, my TILT can still communicate, but its data seems to be all over the place.

Having developed some experience with my TILTS, I think of them as instruments that excel at recording broad trends. Hydrometers are far, far superior at making spot measurements. I believe most brewers would agree with that assessment.

I wouldn't make any rash adjustments based upon the early readings of your TILT. Easier said than done, I know.

 

[dmtaylor]

Don't trust the Tilt. It's not right.

You definitely don't need to add any more yeast. It might help though if you removed the pressure. Then just let 'er go for a couple weeks.

 

[CascadesBrewer]

I have read where pressure fermentation speeds up, not slows down.

The theory is that you can ferment a warmer temps (which speeds up fermentation vs a lager at say 50F) but the pressure will suppress the esters that would normally be created at warm temps. The pressure and additional CO2 present does put stress on the yeast. I have had good luck with 2 packs of dry yeast into 1.100 range beers, but I tend to "open ferment" for the first few days to lessen the yeast stress (where "open" means the fermenter is in my chamber with a piece of foil over the top). A second round of oxygenation after 24 hours might help as well, even when using dry yeast.

 

[hilljack13]

Quick update.

Was gone over the weekend. TILT gravity was 1.028 when I left (Friday morning) and upon return early this afternoon I get a TILT reading of 1.018. IF all is close this thing is running 9.88%ABV!!! I plan to transfer to key in a few days as long as there is no more gravity movement.