S-04 Esters at Low Temps?

Yeast & Fermentation
1

I’ve read up on S-04 and how it has a potential to produce fruity esters at higher and even moderate temperatures but I’m still getting them at fairly low temps. Any idea why this is?

I brewed the Nut Brown Ale extract kit over the weekend and I’m about 84 hrs (3.5 days) into fermentation and starting to get some pretty intense banana scents. I sanitized very well, used an immersion chiller to get to about 80-90 and then used two gallons of refrigerated water to get the rest of the way down. I pitched at ~70 degrees and then moved right into a pre-tempered cooling chamber (I’m using a wine chiller with temp control). My ambient has been fairly stable at 57 +/- 2 degrees (room temp/humidity data logger used for records) and the strip thermometer on the carboy has been steady at 58 since the first 12 hrs. This is right at the low end of “ideal” temps for this yeast.

Any thoughts?

Also I used 2.5 gal of tap water for boil and then the remaining water was bottled off the shelf.

2

I’ve had banana from that yeast at temps around 70. When I keep it at 64 it’s not been noticeable

3

Yeah I have too. I way below 64 now though. Is it possible that it’s just coming out in high volumes now during actI’ve fermentation?

4

I’m not sure, never used that yeast that cool before. I’ve had us05 give off some fruity esters at around 58 degrees that where very noticeable in a cream ale. If you pitched at 70 and it stayed there for a while I’d guess that’s where the banana came from. I’ve had good luck pithing at ,or slightly below the temp I will ferment at. Which is usually about 64 degrees.