Kölch with SafAle K-97 and lot of krausen still left in fermenter after 13 days

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Zteelblade

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I made already quiet lot of beers but never seen such high amount of krausen still left after 13 days. There has not been sign of any activity for like 5 days, but the foam/krausen looks like it would be in middle of fermentation (about 1-1.5cm & 0.4-0.6 inch thick).
Is this something normal for this yeast ? Usually the krausen always disappears after the fermentation is complete.

Would be time to cold crash it but I'm not sure if I can cold crash it like that. Should I rather give it more time?

I'm pretty sure the fermentation is complete. I raised the temperature at end to 20c / 68F in order to finish it of after the fermentation began to slow down.
 
My experience with K-97 is similar. Fermentation is complete, but the krausen remains.
 
What does your hydrometer tell you about the state of fermentation?

It doesn't have to be a guessing game.

Near expected FG? Stable readings 3 days apart? Fermentation is complete.
 
If I would take reading, I would need to expose the beer for oxygen, no tap in fermenter. I'm very certain the fermentation is complete.

I have done 40 patches of beers and based on the activity in airlock and rather lowish OG, and the given time, I could not see how this beer would be incomplete. It started normally, the bubbling speed is normal for that OG. I use yeast nutrient, give wort oxygen etc. Think it was already finished 5-6 days ago.
Beers always fermented in 7 days or less so far (and never had unfinished fermentations), except few philly sour yeast brews/lager/belgian quads that need more time for specific reasons.

Just never seen the krausen stay like that before.

EDIT: And if this is normal for this yeast, Would it still stay over cold crash also? And will it be a problem in bottling then (like introducing too much yeast to bottles)?
 
I haven't used k-97, but in my experience with verdant (another long lasting krausen yeast), the cold crash does cause the krausen to drop.
 
how is K-97 for a kolsch? I have some but I never used it since I was able to get a few packets of kolsch yeast.
 
Don't think you have to bottle or keg today. I've always found that several days or weeks longer are not nearly as bad as one day too soon.

In most cases the longer periods were the better tasting and cleaner beers.
 
I've made cream ales with K-97 that, given enough time in cold storage (a month or two!), are absolutely brilliant -- among the clearest beers I've ever made.

I've read somewhere that WY1007 and K-97 are closely related. They certainly seem to have a similar taste, though maybe WY1007 clears faster? (It's still pretty slow.)
 
how is K-97 for a kolsch? I have some but I never used it since I was able to get a few packets of kolsch yeast.

I just did a batch of Kolsch with it a few months ago, a SMaSH with Rahr North Star pilsner and Mt. Hood. I ferm in a Brew Bucket, so wasn't able to watch the krausen, but I had heard the yeast takes its time, so I waited just over 3 weeks. Good thing, because fermentation got a second wind after a couple weeks and I had airlock activity for a while. After 3 weeks, I took samples (drain valve is nice--not having to pop the top). FG leveled out by day 24 and I bottled. The krausen had dropped by then. I didn't cold-crash.

I was impressed with the flavor--I didn't expect it to be as close to a real Kolsch flavor as say WY2565 or WLP029, but it was damn close. Those delicate Kolsch flavors were present. I had kept the ferm temp on the low end, around 64, a few days D-rest at 70, then back down to mid-60s to finish.

It takes a while to floc, so give it time. After 3 weeks conditioning, it had mostly settled in the bottles and poured bright.
 
I have tried. With K-97, gelatin did not work for me. And for others either that I have seen online. This yeast is extremely resistant to flocculating no matter what you try.

I just coldcrashed kolsh last week with k-97 and 6 gramms of gellatin in 30 liters keg.
Before being coldkrashed in keg it was coldcrashed in primary fermenter for 5 days at -1c and still had some yeast on top.
Beer is crystal clear after one week at -1 C.
 
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how is K-97 for a kolsch? I have some but I never used it since I was able to get a few packets of kolsch yeast.
I have only good experience. My last is at 8th day, fermentation is over. I will keg in 2 weeks max. I used 2qt starter. 1qt to wort, the rest to recover yeast for freezing mixed with 25% glycerine and water. Yeast is 1:1 with this mixture.

I saw krausen foam remaining after the starter was ready.
 
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