Does krausen height have anything to do with healthy fermentation?

[EyePeeA]

26 hours into fermentation and the highest my krausen got was 1.5 inches. For past brews, it was always about 3-5 inches high at this point.

Using a big starter of Conan yeast at 66-68F. The airlock is bubbling steadily every second.

 

[Sailingeric]

I wonder that too.. I have had minor krausen and big krausen.

 

[GuldTuborg]

Not really. It's more a function of recipe, OG, temperature, yest selection, and a few other minor variables. "Health" of fermentation is very low on that list.

 

[EyePeeA]

@GuldTuborg

My OG was 1.078 ish. It's a double IPA at 5.5 gallons in a 6.5 gallon carboy. I pitched over 400 billions cells.

I have a big bottle of water next to the fermentor in the same room. The water has been a steady 61-63 degrees, while the fermometer on the carboy reads 64F.

Can I assume that the actual fermentation temperature is a bit higher than both of these figures... around 66-68F?

 

[GuldTuborg]

Can I assume that the actual fermentation temperature is a bit higher than both of these figures... around 66-68F?

Maybe. It's tough to say. Sanywhere from 2-10F above ambient is pretty normal. You'll see larger rises in temp in smaller rooms, at high kraeusen, with higher gravity worts, at higher temps, etc., and smaller rises when the situation is the opposite. The delta between ambient and beer temp could change by the hour.

Yeast strain selection might be the largest factor in determining kraeusen height and longevity. Nonetheless, I wouldn't worry much unless you have reason to think you're not getting fermentation at all, or unless it's going nuts and you need to switch to a blowoff tube setup.

 

[flars]

@GuldTuborg

My OG was 1.078 ish. It's a double IPA at 5.5 gallons in a 6.5 gallon carboy. I pitched over 400 billions cells.

I have a big bottle of water next to the fermentor in the same room. The water has been a steady 61-63 degrees, while the fermometer on the carboy reads 64F.

Can I assume that the actual fermentation temperature is a bit higher than both of these figures... around 66-68F?

The fermometer strips have been shown to be within 1°F of thermowell readings. Your cool fermentation temperature will keep the fermenting yeast from becoming overly aggressive, compared to warmer fermentation temperatures, reducing the temperature rise over the ambient temperature.

 

[EyePeeA]

Small room indeed.

The airlock is bubbling like crazy. Just the krausen height I was worried about.

 

[joshesmusica]

It's more a function of how flocculent the yeast is than anything. The more flocculent they are, the more they are able to move up and down in the fermentor, and the more co2 is being pushed out, creating the krausen foam. If you're looking for it to also clear up pretty quickly, that large amount of foam is a good thing. I would likely attempt to warm it up a bit after the vigorous part of fermentation is finished. One bad thing with highly flocculent yeasts is that they can possibly leave your FG a bit high.

 

[GuldTuborg]

It's more a function of how flocculent the yeast is than anything. The more flocculent they are, the more they are able to move up and down in the fermentor, and the more co2 is being pushed out, creating the krausen foam.

Seems fishy. How do you explain weizen strains, which are known for being some of the least flocculent brewing strains, yet produce huge kraeusens?

Other examples abound. I like English ales, so I use a lot of them. WY1968, super flocculent very average kraeusen. But, if I use 1318, which doesn't sediment nearly as quickly or as completely, I get enough kraeusen to cover Texas. I'm not seeing the relationship. What am I missing?

 

[EyePeeA]

It's more a function of how flocculent the yeast is than anything. The more flocculent they are, the more they are able to move up and down in the fermentor, and the more co2 is being pushed out, creating the krausen foam. If you're looking for it to also clear up pretty quickly, that large amount of foam is a good thing. I would likely attempt to warm it up a bit after the vigorous part of fermentation is finished. One bad thing with highly flocculent yeasts is that they can possibly leave your FG a bit high.

Conan is a low floc yeast. I will definitely raise the temp after day 4 or 5... From 66-68 to 70-72.... (was going to do that anyway).

The fermentor has been bubbling every 1/2 second to 1 second for almost 40 hours now...without slowing down. So quite vigorous.

I just thought I would need a blowoff tube with 1 gallon or less headspace, but it seems that I don't.

 

[bransona]

Krausen is unrelated to ferment health. I had a massive krausen wind up in stuck fermentation, and a complete lack of krausen and yet completed fermentation. As stated above, it's just recipe, yeast, etc.

 

[EyePeeA]

Thanks all.

I think ill be fine. While the krausen wasn't huge, the fermentation itself is quite vigorous.

 

[Gavin C]

It is totally unrelated to an optimal fermentation or the flocculation properties of a yeast as has been mentioned.

*The one obvious exception to this blanket statement of NO is a runnaway hot fermentation where a massive krausen has a better chance to form as the rate of fermentation is so high. Kind of like a controlled v explosive chemical reaction.

Tightly controlled fermentations with varied Krausens.

Here is an example of a poorly flocculant yeast strain with a large Krausen

Here is an example of a poorly flocculant yeast strain with a smaller Krausen

 

[dpeters]

I recently brewed a beer where I had zero kräusen which I have never had happen but I thought it was because of the yeast I used WLP515. I reserved and froze a couple of quarts of the wort to use for a starter and later pitched WLP002 into it and that starter had zero Krausen also so I now think it must have something to do with wort and not the yeast. The original beer did turn out perfectly fine.

 

[joshesmusica]

Seems fishy. How do you explain weizen strains, which are known for being some of the least flocculent brewing strains, yet produce huge kraeusens?

Other examples abound. I like English ales, so I use a lot of them. WY1968, super flocculent very average kraeusen. But, if I use 1318, which doesn't sediment nearly as quickly or as completely, I get enough kraeusen to cover Texas. I'm not seeing the relationship. What am I missing?

Yeah. I don't know. Ignore me. I know I read it before, and because the last thing I read on yeast was the book by jamil and chris white, I assumed I had read it on there. Can't find it anywhere now though.

I probably just believed it at the time because it made logical sense. The better they are at flocculating, the more they'll be able to move around in the wort. The more movement, the more co2 gets nucleation sites, the more bubbles/foam there becomes.

From some stuff I read when trying to look it up, it seems it is more a function of how crazy the yeast go, and therefore how much co2 is being produced at one time.

 

[EyePeeA]

Makes sense. Conan is a low to very low floc yeast.

1 hour after putting the wort in the carboy, the top half was clearing up quite nice, but the bottom half looked almost solid with trub and hop matter.

About 7 hours later fermentation began, and a few hours after that, all of the wort looked like Sunny D orange juice with 1.5 inches of krausen. This lasted for a day with the airlock bubbling 60-120 times per minute. The second day, the same thing, but the krausen rose an additional inch.

I don't have proper temp controls other than a thermometer, fermometer, and a vessel of plain water set next to the wort. Every time I tested the water, it hovered around 60-62 F while the fermometer has been reading 62-66 F. So I'm guessing the actual fermentation temperature... which is still quite vigorous at 60 blips per minute, is around 66-68 F.

 

[jwalker1140]

I've puzzled over this for years and haven't come up with anything definitive.

On 1/8/2016 I brewed an amber ale, OG 1.057, fermented at 67F. I made a 1L starter from a pouch of 3-wk-old 1272 and the beer had a 6" krausen. I kegged 2 weeks later and pitched ~1 cup of slurry into a pale ale the very next day and only got a 1" krausen. The OG of the pale ale was 1.052 and the grain bill was pretty similar (just different L of crystals and more pellet hops), but the lag times, the water and ferm temp/conditions were identical.

I just kegged the pale ale yesterday and both it and the amber taste fine, so I'm not super worried, but not understanding the reason for the inconsistency still nags at me. And I have brewed the exact same recipe back-to-back and observed the same thing. It's just that this was just the most recent instance.

My best guess is that it has something to do with yeast vitality.

 

[EyePeeA]

My best guess is that it has something to do with yeast vitality.

Maybe a combo of that and other factors.

I pitched two packs of Gigayeast Vermont Ale yeast, which is quoted at 400 billion cells for both packs. At 71% viability because of the date, I made a starter w/shaking and definitely pitched over 400 billion cells. So vitality in my case was a non-issue.

 

[joshesmusica]

Maybe a combo of that and other factors.

I pitched two packs of Gigayeast Vermont Ale yeast, which is quoted at 400 billion cells for both packs. At 71% viability because of the date, I made a starter w/shaking and definitely pitched over 400 billion cells. So viability in my case was a non-issue.

Did you cold crash and decant the starter? It shouldn't make a huge difference, but he was talking about vitality not viability.

In fact, brulosophy has done experiments between regular starters, vitality starters, and pitching un-cleaned slurry. There hasn't been a perceptible difference in either case.

 

[jwalker1140]

My starter spent 24 hrs on a stir plate, I cold crashed for 2 days, then I decanted and pitched once it reached the same temp as my wort.



And right, I'm talking about vitality, not viability. I assume the viability was pretty high given there was only about 2 weeks between pitch and re-pitch.

 

[joshesmusica]

My starter spent 24 hrs on a stir plate, I cold crashed for 2 days, then I decanted and pitched once it reached the same temp as my wort.



And right, I'm talking about vitality, not viability. I assume the viability was pretty high given there was only about 2 weeks between pitch and re-pitch.

That's very interesting. If you continue to keep records of this sort of activity, I know I, for one, would like to hear the results.

 

[Gavin C]

Curious.

What's the difference between vitality and viability of yeast from a practical stand point?

I don't see one.

 

[EyePeeA]

Yes. Cold crashed and decanted 80% of clear wort, using the remaining 20% to stir up the slurry.

 

[jwalker1140]

Viability is how many yeast are alive. Vitality is how healthy they are and how well they can handle fermentation.

 

[EyePeeA]

The airlock stopped bubbling so vigorously on day 3, and the krausen completely dropped. I'm getting a bubble every 8 seconds now.

The beer is completely murky and I hope it clears in time. Looks like someone poured orange juice in dirty dish water.

I did some tests with the vessel of plain water in the same room... The fermometer and thermometer in the water vessel read the same temps.

I think I didn't have a huge krausen because I fermented at about 62-63F for 2 days... At these low temps, I guess the yeast was not as boisterous as it could've been.

I moved the carboy to another room and both fermometer and thermometer are reading 69-70F now.

Best results with this particular yeast was reported to be about 68F so we will see how this ends up tasting in Mid March.

 

[Chrisbrewbeers]

I read somewhere that a good size 60 minute bittering charge will help with a bigger krausen. This seems true in my experience. I can't remember exactly who but it was a commercial brewmaster.

 

[EyePeeA]

I read somewhere that a good size 60 minute bittering charge will help with a bigger krausen. This seems true in my experience. I can't remember exactly who but it was a commercial brewmaster.

Makes sense. I used 14 ml hop extract as my bittering charge. It was my only kettle hop addition.

Pellet hops were added during whirlpool.

 

[jwalker1140]

That's very interesting. If you continue to keep records of this sort of activity, I know I, for one, would like to hear the results.

Just another data point. I'm on Day 10 of a Moose Drool clone using 3rd gen Wyeast 1272. This time I decided to take ~250ml of 12-day old slurry and make a 1L starter. It took off right away and had a huge 6" krausen, just like the first gen, and quite unlike my 2nd gen which only had ~1" (though the 2nd gen beer tastes perfectly fine).

Not sure I'm really willing to draw any conclusions from this yet but I've repitched slurries enough times (probably 50+ batches) to convince me that I wouldn't have seen that krausen if I didn't make up a starter. My experience has been that repitching generally tends to produce less and less krausen with each successive batch.