Very aggressive yeast.

[JProulx]

Hey guys,

I'm working on my third extract recipe right now (pumpkin porter, hopefully in time for Halloween). The OG is around 1.057. I wanted to ask about what to expect here.

I pitched my yeast (Safale S-04) at 64F. About 5 hours later, my fermometer was reading 67F. The ambient temperature in the room is 70F.

When I woke up the next day (12 hours after starting primary) temperature was up to 68F and krausen was already starting to form up. I started a swamp cooler to keep it in check, but the temperature kept climbing. The fermentation was so aggressive, I could actually see motion throughout the wort. The krausen peaked at about 24 hours, with temperatures hanging around 70F.

I caught it sitting at 72F after 30 hours. I tossed some ice into the cooler and held it to 68. It's still at 68 now (42 hours in), and the fermentation has slowed. Krausen is receding and the airlock is bubbling at a bit more reasonable of a pace.


So. This looks like it was clearly too high. What esters can I expect off of Safale S-04? What tips do you have for keeping this temperature in check in the future? My first two brews used Nottingham, and it was NEVER this aggressive.

 

[Nelrock]

I use the swamp cooler. I keep frozen water bottles in the freezer...toss them in the tub as needed.
If you caught the temp at 72...I wouldn't worry too much. The slowing you noticed might not have had as much to do with lowering it 4 degrees as the fact it was just at a point it was already slowing.

 

[JProulx]

I use the swamp cooler. I keep frozen water bottles in the freezer...toss them in the tub as needed.
If you caught the temp at 72...I wouldn't worry too much. The slowing you noticed might not have had as much to do with lowering it 4 degrees as the fact it was just at a point it was already slowing.

I've only used swamp coolers for their evaporation effect in the past. I'll try frozen water bottles for my next brew.

I'm not too worried about the fermentation. It was very aggressive, so I wouldn't be surprised if it's on its way towards the clean-up phase already. I'm more worried about what esters to expect. I've heard pineapple is one you get off of S-04, which, while delicious, doesn't fit well with a pumpkin porter!

 

[stpug]

S-04 is fairly well known to give some off-putting "esters" outside of it's optimum fermentation temperature range, and based on folks experiences with S-04 it seems like it's true optimum fermentation range is 64F to 64F . The fact that you put it in a porter might help. Definitely too warm for this yeast. I've read to certainly not exceed 68F but 64F is perfect

S-04 is also well known for fermenting VERY fast (1-2 days) and dropping out a little early (a couple points higher than expected). So don't be surprised if you see your brew drop clear after just a couple days of fermentation. Keep your beer on the yeastcake for a little extra time if you detect off flavors and maybe the yeast will clean some of it up for you. Otherwise, time in a bottle/keg might help mellow any off flavors a little bit.

Tips for keeping temp in check: Pitch at a cooler temperature, put in a water batch immediately, keep the bath a few degrees cooler than your expected fermentation temp. I pitch in the low 60s usually, and keep the water batch at about that same temp. It makes for a slightly longer lag phase (in my experience) but once fermentation begins the temperature just slowly creeps up to where I want it. Plus it gives me time to add ice packs if I see it starting to get above my desired temperature range.

My immersion chiller can only get to about 75F in the summer so at 75F my wort goes into a fermenter, and then into a much cooler water bath. I leave it there for several hours (3-4 usually) until it gets into the low 60s before finally pitching my yeast. It works well for the most part. I just have to plan my brews so I'll have 3-4 more hours of awake time so I can pitch when it's cool enough. In the winter, my groundwater is freezing so I can get to 60F or cooler within 15 minutes with my immersion chiller.

 

[ncbrewer]

I've noticed that the temperature sometimes climbs during the lag phase. I check the temperature of both the fermenter and the bath water every hour and add ice bottles as long as it keeps trying to heat up - and keep the bath temperature in the upper 50's to help keep the fermenter temperature under control. Fermenter still gets to upper 60's and even 70 sometimes.

 

[JProulx]

S-04 is fairly well known to give some off-putting "esters" outside of it's optimum fermentation temperature range, and based on folks experiences with S-04 it seems like it's true optimum fermentation range is 64F to 64F . The fact that you put it in a porter might help. Definitely too warm for this yeast. I've read to certainly not exceed 68F but 64F is perfect

Ahaha 64F to 64F, hey? I'll keep that in mind for the future. Any knowledge about what flavour of esters to expect?

My plan was 2 weeks in primary and 4 in the bottle. I would like more conditioning time, but Halloween has refused to reschedule itself. I expect the specialty malts and pumpkin spice to cover up some of my mistakes, at least!

 

[Devilsnight]

I have a bitter brewer clone in the fermenter right now. Used s-04, Primary fermented in 48hrs or so. Then slow steady bubbling for the rest of the week. Starting gravity was dead on, when I checked at 7 days i was shocked to see it at 1.007 . Haven't got a reading that low before. Tasted fine, no off flavors what so ever. I kept it at 68-69 the whole time.
Also I'd say its the clearest beer i've seen yet, till I dry hopped. just thought i'd share my s-04 experience.

I think you'll be fine. You'll have almost a month of bottle conditioning.

 

[snaps10]

I've used US04 in about a dozen brews. I have also used it in a pumpkin Barleywine (OG 1.120).

I fermented that brew at 68 ambient in my temp controlled chamber. Max temp was 70. I got a little pineapple, but feel that it went well with the pumpkin and spice. I did pitch a huge starter, as to not strain the yeast and had visible fermentation within hours and blowoff within 12hrs.

I'd give it a little time on the yeast cake, don't rush this one. Let the yeast do what they do best and clean up the beer. Like was said above, the fact that it's a porter may end well for these flavors. RDWHAHB.