Why such a delayed fermentation?

[DarkUncle]

I brewed an OG 1.082 beer on Saturday. Made a yeast starter as I normally do with a Trappist yeast and pitched. Up until yesterday there was absolutely zero activity. I then bought some more yeast which should be here tomorrow so I could repitch.

Well I went into the garage and heard a bubbling sound coming from my fermenting chamber. It couldn't be I thought. I opened the lid and there was the big mouth bubbler bubbling away along with a layer of krausen. Yesterday it looked like a container of coffee with not a single bubble.

Why did this take so long to get going? And now I'm worried that it may end up being a weak fermentation with possible infection having wort sitting so many days. I've never had it take this long for yeast to get going and my process was completely the same.

 

[kombat]

How did you aerate? How big was your starter and how did you prepare it? What temperature do you have your fermentation chamber set to?

 

[DarkUncle]

My process was completely the same. 2 liter starter the day before on a stir plate.

Once wort was down to pitching temp I aerated it with oxygen out of my diffuser stone for about 40 seconds then pitched.

Went into my chest freezer which holds temp between 62 and 66 consistently. Have another beer in there which just finished fermenting last week and is now just conditioning.

 

[Yourrealdad]

What was your starter temp at when you pitched it? Maybe it was warm like 72° and then the yeast shut down a little when you pitched it to 62° and it took some time to get back into it?

Also I wouldn't consider 62-66 very consistent IMO. I hold my temps within +/-1° swings so max a 3° swing (rare). If it gets up to 66° and then back down to 62° that is going to put a lot of yeast to sleep.

Looking at trappist yeasts 62° and really under 64° is on the low side. I also ramp up the temp a degree a day with mine until I am at around 70°

I usually have vigorous fermentation within 12-24hrs, but I have had some lagging on a couple batches.

I wouldn't worry about it to much and try ramping up the temps.

If this happens again then it might be an issue with process, but my guess is just a weird yeast issue.

 

[Gavin C]

Trappist strains like WLP300 or Wyeast 1214 are notoriously slow starters. It is very possible that little if any increase in cell count occurred in such a short time with these strains.

FWIW I make starters Monday/Tuesday for a Weekend Brew

 

[DarkUncle]

Yeah I may start making starters a few days earlier. As far as the temps go in the chest freezer I'm using a non digital temp controller so the 5 degree temp swings are just the norm with these. And that's the actual air temp inside the freezer not the wort. So I doubt those 5 degree swings will change the wort temp all that much. I mean 5 gallons of liquid takes a good amount of time to change temps based on the ambient temps. I figure if the air is swinging between 62-68 the wort temp should pretty much hold consistent.

 

[Gavin C]

Yeah I may start making starters a few days earlier. As far as the temps go in the chest freezer I'm using a non digital temp controller so the 5 degree temp swings are just the norm with these. And that's the actual air temp inside the freezer not the wort. So I doubt those 5 degree swings will change the wort temp all that much. I mean 5 gallons of liquid takes a good amount of time to change temps based on the ambient temps. I figure if the air is swinging between 62-68 the wort temp should pretty much hold consistent.

There is a better way to control the temperature of the beer at target +/- 0.3C but I'm sure you are doing what you prefer. Those temperature swings leave you with no knowledge of the beer temps and their stability.

 

[DarkUncle]

Yeah I know. It's just always worked for me. I do have plans to pickup a thermowell for the fermenters. Just haven't gotten around to it yet. Always something to buy to improve processes with this hobby. It's in the queue though. [emoji3]

 

[Gavin C]

You don't need a thermowell. In fact you'll be better off not using one.

Fix the probe to the carboy. Insulate it from ambient, set your temp to where you want it, set the hysteresis on your controller to the minimum and the dealy to the max and you're all set.

 

[kombat]

You don't need a thermowell. In fact you'll be better off not using one.

I still don't see how you'd be "better off" not using a thermowell. A thermowell is the ideal solution. Affixing the probe to the outside of the fermenter and insulating it is probably good enough, but it's a substitute for those who don't have thermowells. A thermowell is (in my opinion) the optimal solution.