My first Swamp Cooler

Ok, got my first swamp cooler going. Typically my basement is 65 and my fermenters have been pitched at 70 and run up to 73/74. My product is fine and I don't think I'm getting too many esthers (hold the butter). But, I was really wanting to ferment lower... anyhow with the cooler and no ice added, just water I'm at 64. I've got what seems like a good fermentation 11 hours after the pitch. So, my question is - 64 is the bottom of my Wyeast 1968's range. Can I leave it here or should I remove some water from the swamp and let it get up a few degrees?

Are there taste benefits if I can hold it at 64?

Thanks!

:rockin:

Just for grins, hold it at 64, and see how you like your beer. I was amazed when I started actually holding the ferment at 65F - so much cleaner, crisper, professional-tasting...(professional???) well - just try it and you'll see what I mean. You will probably strive for that range from now on

if you wanted to warm it up you could just add some hot water

What kind of things happen at the low end of the yeast's range, I mean below the low number on the range can there be off flavors or do you just get into danger of the yeast going dormant?

If you are right at the lower range of your yeasts, you might be a few degrees above that. Yeast activity raises the temperature inside a few degrees. although there is a caveat - its based on activity. For, I brewed an IPA that was actually below the ideal temperature by a few degrees and I had very slow activity for almost 2 weeks (best beer I've had todate). As a result, it probably was only up 1 degree at most. However, a beer I brewed near the upper end fermented pretty vigorously and raised the temp probably 5-8 degrees (and put it slightly on the high end).

My thoughts are this on low temperature fermentation. It takes longer but requires you to wait longer. But as with all things home brew, the longer you wait, the better it gets. Follow the logic? Nope?

lower temps will give you less ester production

I follow you man, I don't mind waiting at all. I'm getting a good steady fermentation now (approx 43 hours after the pitch and temp is up to 65 due to heat of fermentation. I typically do 21 days in the primary then into the bottle for 4 weeks. I am patient... I just don't want bad tastes in the brewski.

I ferment almost all of my ales at the very low end of the yeast strain's temperature range, or at times a bit below. It gives a much "cleaner" profile, which is what I like in my IPAs, APAs, AAAs, etc. If I want an estery profile (like with Northwest ale yeast), I'll go closer to the high end, but never over. I really like the results, and haven't had any off flavors as a result.

Of course, hand in hand with the fermentation temperature is proper yeast pitching amounts. Stressed yeast is what makes the beer's off-flavors. High fermentation temperatures especially show that, but it can happen when the yeast is stressed from underpitching as well. The key is to pitch enough yeast at the beginning and keep it at the proper temperature.

I was using the Northwest Ale Yeast most of this summer and fermenting at the upper range. I had very decent results. I just learned about the swamp cooler where I can now explore the lower ranges and it is good because I'm getting into my favorite style which are bitters. Both London Ale and 1968 supposedly do better in the mid 60's so I'm psyched to get there. I pitched this batches yeast (1968) at about 67/68 and the cooler had the fermenter down to about 64 for the first 10 hours, it started bubbling at about 12th hour and going strong now at the 45th. I'm expecting a decent length fermentation because in the past my 1968 ferms at 70-72 have lasted 6-7 days at least.

What differential of temp can shock the yeast? How many degrees?