Northy 12 quadrupel fermentation - Very fast, then stopped?

[maartendc]

Hello Everyone,

Last Sunday, I brewed the Northy 12 Quadrupel Belgian Ale with an Extract Kit from Northern Brewer: https://www.northernbrewer.com/products/northy-12-belgian-quad

I am fermenting in a plastic bucket (bottling bucket with spigot actually). Using Safbrew Be-256 dry yeast. 2 packs, hydrated. Using a Thermograph stick-on thermometer for temp readings.

Now, I am a little worried about the state of my fermentation, 48 hours in. The progress has been as follows: (room temperature has been 65-67F at all times)

- Pitched the wort at 68F. Hydrated the dry yeast. Liquid yeast temp was 75F.
- After 6 hours, temperature in the fermenter was 66F ). Decent bubbling in the airlock (1 bubble every 2-3 seconds)
- After 18 hrs, temp was at 65F. Good airlock activity, about 2 bubbles per second.
- After 24 hours, fermentation went crazy. Wort got into the airlock. Airlock stayed in place. Temperature unknown. (I was at work, the wife told me about the "incident")
- After 30 hours, airlock was full of wort, temperature was now at 74F. Bubbling was slow again, at about 1 bubble per 3 seconds. I cleaned out the airlock, re-sanitzed and put it back in. Sloshed the bucket around a bit with cleaning. After putting the airlock back, no more bubbling activity.
- After 44 hours, temp at 74F, no airlock activity.

Now I am a little worried that the fermentation was so violent and sudden after 24 hrs, but after 30 hours, everything seemed to slow down / stop significantly. I have heard airlock activity is not a good indicator of fermentation activity, but still... From violent to nothing over the course of 6 hours is a bit strange?

Did I do anything wrong? Did moving the bucket around while cleaning harm the fermentation?

I have now put the fermenter in a water bath (evaporation cooling) at 67F in order to get the temperature down a bit. Ideal temperature for this yeast is 59-68 F.

I pitched at the warmer end of the yeast temperature range, but temperatures seemed good at first. Is it a good idea to try and cool the fermenter down now to under 70F?

Any advice would be appreciated! Thank you!

Maarten

 

[cooper]

Hey Maarten,

67F should be good for the remainder of the fermentation. I wouldn't base whether or not its fermenting on the airlock activity.

A better way to test would be to take a hydrometer reading today, then take another one tomorrow and then the day after. If it's the same on all three days then fermentation is done and you can either proceed with packaging or let it condition a few more days then cold crash and package per your usual routine.

 

[thehaze]

Belgian yeast like heat, so yours will be OK. That's a recommended temperature range, but most belgian yeast can be fermented hotter, which most times will result in more esters, but those are nice.

See how you like it this time and next time ferment it much cooler. You should just let the yeast finish fermenting. If you cool it down now, you could risk not helping the yeast finish and clean after itself. The bulk of fermentation - at the point where esters, phenols and off flavours develop - is over and with most yeast ranges from 2 to 4-5 days.

 

[isomerization]

After putting the airlock back, no more bubbling activity.

This would lead me to believe that you have a leak. If it was bubbling prior to removing the air lock for cleaning then it should still be bubbling once put back on.

But yes, definitely take a hydro reading so you can track progress.