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General Category => Yeast and Fermentation => Topic started by: mpietropaoli on September 18, 2012, 09:28:04 PM

Title: Very quick high krausen with S-04
Post by: mpietropaoli on September 18, 2012, 09:28:04 PM
Wow, did a double brewday with 2 american IPAs (both around 1.062).  Pitched about 1 cup of pure slurry into each, harvested from a 2L starter of new S-04.

Pitched on Sunday morning at 64 degrees, had visible airlock activity within 4 hours (temp maintained), went to go top crop some this afternoon, and boom, the krausen had already dropped....on both fermenters!

Has anyone had a krausen drop within 48 hours?  I know I borderline overpitched, but that is damned quick!
Title: Re: Very quick high krausen with S-04
Post by: bigchicken on September 20, 2012, 10:02:22 PM
I don't top crop, but yes I've seen a full krausen drop out completely in a 12 hour timeframe. I should note it took 3 days to form a krausen, but then it was done super quick. I used a ton of sugar in that beer and was not using s-04. Not sure if the sugar was part of the result or not.
Title: Re: Very quick high krausen with S-04
Post by: hamiltont on September 21, 2012, 02:58:41 PM
S-04 is a very, very fast fermenter. In my experience almost all activity is over in a couple of days. It still needs time to clean up though. Cheers!!!
Title: Re: Very quick high krausen with S-04
Post by: euge on September 21, 2012, 03:38:42 PM
I've had a few ferment out that fast and with less yeast. Sounds like you definitely over-pitched with the cup of pure & fresh yeast. ;D The beer should be fine and a faster turnaround isn't always a bad thing!
Title: Re: Very quick high krausen with S-04
Post by: bluesman on September 21, 2012, 04:43:14 PM
My experince with S-04 is such that it ferments quickly and flocculates rather quickly (68F) as well.  I like using it for those reasons alone, although I prefer the equivalent liquid strains particularly WLP002.
Title: Re: Very quick high krausen with S-04
Post by: mpietropaoli on September 22, 2012, 02:51:20 AM
Around the interweb, there is a lot of hate on S-04.  But of course I trust this forum more than any of the others  ;D

Ended up turning the temp controller up to 66, giving each fermenter a few swirls, and hoping for the best.  Saw some consistent airlock activity for another 48 hours (originally thought it was just the CO2 purging as the temp warmed, but it was pretty consistent over that time).  Going to take a gravity reading and see where I'm @ tomorrow. 

The gravity before I swirled was only 1.030 or so...hopefully i dropped to low teens

voila, the S-04 Haterade!
http://www.homebrewersassociation.org/forum/index.php?topic=13175.15
Title: Very quick high krausen with S-04
Post by: mpietropaoli on September 23, 2012, 01:10:16 PM
One of the beers has fully stalled at 1.028...just under a cup of slurry, at about 62 degrees.  Hasn't moved since two days after pitching
Title: Re: Very quick high krausen with S-04
Post by: euge on September 23, 2012, 01:18:15 PM
One of the beers has fully stalled at 1.028...just under a cup of slurry, at about 62 degrees.  Hasn't moved since two days after pitching

Without knowing the grain-bill my suggestion is to let it warm up slightly, and if the beer hasn't dropped further in a few days rouse it gently (or swirl).
Title: Very quick high krausen with S-04
Post by: mpietropaoli on September 23, 2012, 01:58:13 PM
Did that after 3 days and the krausen dropped.  Still didn't drop the gravity.  Should I pitch some champagne yeast?
Title: Re: Very quick high krausen with S-04
Post by: euge on September 23, 2012, 03:08:25 PM
I say consider it done and don't screw around with any champagne yeast. You could try leaving it totally alone for another week or two.
Title: Re: Very quick high krausen with S-04
Post by: nateo on September 23, 2012, 06:12:18 PM
I use wine yeast a lot in beer fermentations. All of them are poor attenuaters in wort, and all but one (1116) can't eat complex sugars at all. I'm not really sure where the idea that Champagne yeast will fix a stuck ferment came from, but it really, really won't help, unless your primary yeast miraculously ate all the complex sugars first, and you only have simple sugars remaining in your beer.

I use S-04 regularly, and you don't really want to make a starter when using it. It's better to just buy an extra pack if you need more yeast.
Title: Very quick high krausen with S-04
Post by: mpietropaoli on September 24, 2012, 12:25:24 PM
I use wine yeast a lot in beer fermentations. All of them are poor attenuaters in wort, and all but one (1116) can't eat complex sugars at all. I'm not really sure where the idea that Champagne yeast will fix a stuck ferment came from, but it really, really won't help, unless your primary yeast miraculously ate all the complex sugars first, and you only have simple sugars remaining in your beer.

I use S-04 regularly, and you don't really want to make a starter when using it. It's better to just buy an extra pack if you need more yeast.

I got the idea from Chris whites book.

What about racking to Another s-04 cake?
Title: Re: Very quick high krausen with S-04
Post by: nateo on September 24, 2012, 01:11:00 PM
I got the idea from Chris whites book.

What about racking to Another s-04 cake?

Are you talking about Yeast? I have that book but I don't remember seeing that in there. What section was it in?

Racking onto a yeast cake is the most reliable fix, from my experience.
Title: Very quick high krausen with S-04
Post by: mpietropaoli on September 24, 2012, 04:50:42 PM
Unless I am confused, it is in the troubleshooting section.  Since I'm a big advice-asker, it could very well have been from uninformedhomebrewer.com or donttrusttheinternetforbrewingadvice.com and the experts don't recommend anything of the kind!

On the s-04 starter question, why is it not good to do a starter?  The only other thing I could think of is I had the starter in the fridge for 2 days to decant prior to pitching, but I thought it was better to have the yeast cooler than the wort instead of vice versa.
Title: Re: Very quick high krausen with S-04
Post by: nateo on September 24, 2012, 04:59:43 PM
I'll take a look in my copy, but there is really a very narrow range in which champagne yeast would be beneficial.

Most yeasts called "Champagne" yeasts have low nutrient needs and high alcohol tolerance. If you were fermenting the entire wort with Champagne yeast, from my experience, 1.062 to 1.028 is where I'd expect a typical wine yeast would end up.

Wort is made up of a lot of different kinds of sugars, some simple (like glucose), some complex (like maltotriose), some really complex (like dextrins). All yeast used to make booze can ferment simple sugars. Some yeast (and all beer yeast) can ferment complex sugars to varying degrees, but very few yeast (like Brett) can ferment really complex sugars.

So, if your stalled ferment was due to low nutrients or high alcohol, and if there were still plenty of simple sugars left over, then Champagne yeast might nudge the gravity down a bit. Wort is typically nutrient dense, and your beer doesn't have much alcohol, and probably doesn't have many simple sugars left, so I don't think Champagne yeast would help.

I think it's more likely the ferment stalled when the yeast ran out of simple sugars and are having trouble breaking down and eating the more complex sugars.

RE: starters with dry yeast, one of the really cool things the yeast labs can do is build huge energy reserves into the dry yeast. Within the first ~30min of being rehydrated they go nuts, but their activity tapers down to "normal" shortly after that burst. So that burst of energy isn't necessary, but it helps kick off a strong ferment. Once you've gone past that 30min window, the yeast will just act like normal yeast.
Title: Re: Very quick high krausen with S-04
Post by: euge on September 24, 2012, 05:12:33 PM
You don't need to make a starter with dry yeast. Properly treated it (one pack) has enough cells to take care of a beer up to the upper .050's! And if you need more then another pack is easy enough to open.

I've never had any sort of attenuation problems with S-04. Were your "double batches" from the same wort or did you do separate boilings? Extract? Or did you mash? You haven't really supplied us with very much info about your recipe or methods so it is hard to diagnose a fermentation problem over the web.
Title: Re: Very quick high krausen with S-04
Post by: nateo on September 24, 2012, 06:39:04 PM
Under "troubleshooting low attenuation" (p.274-5) Chris White says this:

"Add more yeast. Many brewers ask if they can just toss in some dried Champagne yeast to finish out fermentation. Those who say it works were probably dealing with a beer that had large amounts of simple sugars remaining, as Champagne yeast will not consume the longer wort sugars."

So, I actually haven't read the book in its entirety, but it looks like we came up with the same conclusion re: Champagne yeast.
Title: Re: Very quick high krausen with S-04
Post by: Joe Sr. on September 24, 2012, 06:53:29 PM
Regardless of the benefits (or lack thereof) of Champagne yeast, I just plain don't like the flavor of beers where it has been used.  I've used it (long ago) a couple of times and did not find it to be as "neutral" as people claim.

If you don't have another s-04 yeast cake to use, I'd grow up a starter and pitch that.  I've had some luck doing this, but not as much as using a big ol' cake.
Title: Re: Very quick high krausen with S-04
Post by: denny on September 24, 2012, 07:09:36 PM
Regardless of the benefits (or lack thereof) of Champagne yeast, I just plain don't like the flavor of beers where it has been used.  I've used it (long ago) a couple of times and did not find it to be as "neutral" as people claim.

Exactly the same conclusion I reached.
Title: Very quick high krausen with S-04
Post by: mpietropaoli on September 24, 2012, 08:53:28 PM
OK, so here is some background on the 2 brews:
 
For both, at flameout, I immersion-chilled to ~120 degrees, then dumped the entire kettle into a fermenter (including trub).  I let sit in my fermentation fridge with the temp control probe set to my pitching temp (in both cases here, 65 degrees), then dump the ‘cooling’ fermenter contents vigorously into a clean, sanitized fermenter, leaving the settled trub behind, aerate with sanitized mash paddle for 2-3 min, and pitch yeast.  This gives me a clean yeast cake on the bottom after floc and shortens my brew day.  Have done three different brews this way and had vigorous fermentations. 
 
As I said, for these two brews, I only had one packet of S-04, so a few days before brewing, I made a 1.5L starter, which took off after 5ish hours on the stirplate.  Then I set the starter in the fridge, to be decanted prior to pitching.  The yeast was probably about 45 degrees when I pitched into the 65 degree wort (both batches).
 
Pitched about 0.8 cups of pure decanted slurry into each fermenter about 12 hours after brewing, after vigorous pouring/splashing for aeration.  Since I have one fridge and one temp controller, I set the temp controller to a few degrees below my desired fermentation temp, in this case 61 degrees and 65 degrees, respectively.  The probe was suspended in the chest freezer between the two fermenters.
 
For both brews, it was a 75-minute brew-in-a-bag mash with a single sparge.  Roughly 76% mash efficiency on both.
 
Grain bill for IPA #1 (the one that is stuck @ 1.028ish)
80% Maris Otter
10% Vienna
10% Munich
60 minute boil, magnum hop charge @ 60, various late hops
5.5 gallons in fermenter at 1.061
 
Grain bill for IPA#2 (the one that got down to about 1.018)
80% American 2-row
10% biscuit
10% Munich
60 minute boil, magnum hop charge @ 60, various late hops
5.5 gallons in fermenter at 1.062
 
The krausens on both beers dropped after about 2 days, after which I roused the yeast by swirling the fermenters, then increased the chamber temp to 66 degrees.

The big possibility I am thinking about is that the chamber got too cold and one fermentation continued while the other yeast went to sleep.
Title: Very quick high krausen with S-04
Post by: mpietropaoli on September 24, 2012, 08:56:25 PM
Sorry, also mash temp of 152, roughly 2Q/lb mash thickness. 
Title: Re: Very quick high krausen with S-04
Post by: nateo on September 24, 2012, 09:10:53 PM
IMO it's better to have fewer active yeasts than more inactive yeasts. I'd bet chilling and decanting was your problem. If you properly rehydrate dry yeast, you'll get ~90%+ viability, and 20b cells per gram. Proper temp is in the 100-105*F range, but that varies a bit by strain. IIRC viability will drop by ~10% with every ~10* drop in rehydration temp, but that might not be exactly linear.

It's partially a WAG, but I'd bet you'd have been better off just rehydrating and splitting the packet between the two.
Title: Very quick high krausen with S-04
Post by: mpietropaoli on September 26, 2012, 03:12:43 PM
IMO it's better to have fewer active yeasts than more inactive yeasts. I'd bet chilling and decanting was your problem. If you properly rehydrate dry yeast, you'll get ~90%+ viability, and 20b cells per gram. Proper temp is in the 100-105*F range, but that varies a bit by strain. IIRC viability will drop by ~10% with every ~10* drop in rehydration temp, but that might not be exactly linear.

It's partially a WAG, but I'd bet you'd have been better off just rehydrating and splitting the packet between the two.

Ok, I hear ya, but I pitched almost a cup of slurry!  Most say that is borderline over pitching!  It's just weird.