Fermentation temperature effects

[Herm brews]

In my home brewery, I lack fermentation temperature control. An interior closet under the stairwell serves as my fermentation chamber, and it is one of the coolest places in our home where such activities can be carried out. There is a cheap analog thermometer in this closet, which usually reads between 68F and 72F. As I type, there is a batch of Herm’s Amber Ale, brewed on 10/4 and fermented with WLP090 (San Diego Super Yeast) ready for bottling. At the time of pitching, my wort had been cooled to ~65F, but I know fermentation temperatures rose above that (but to what level, I do not know). Presumably, 75F could be a reasonable assumption. Given that this yeast performs best in the narrow range of 65F to 68F, what effects can I expect from a higher fermentation temperature?

I will be brewing tomorrow (Monday 10/25), a pale ale using some of my recently acquired Azacca hops. On hand, I have more of the San Diego Super Yeast from an overbuilt starter. Also, a packet of US-05, and a partial packet of S-04, as well as Imperial Loki (Voss) from an overbuilt starter. I want a clean fermentation, and my plan was to again use WLP090 from a starter. How will temperature affect this yeast choice, assuming that temp is 5 to 10 degrees above ideal?

 

[Minbari]

If you have a very cool place to put it. Temp control can be as easy as adding heat.

$15 aquarium heater and a $12 stc1000 controller.

As far as off glavours, im no expert, but too cold can cause diacytl and too hot can cause fruity esters to be produced . I usually try to stay in the temp band unless I am purposely trying the enhance an off flavor

 

[Josh Hughes]

Upper temp range can produce more fruity esters. If you are used to a higher temp fermentation then you like this esters. Not tried the Sam Diego. My guess is it may not be as clean as you are expecting BUT some lager tray like 34/70 can be just as clean in the 60s instead of lager temps.
That probably wasn’t much help.

 

[Herm brews]

Upper temp range can produce more fruity esters. If you are used to a higher temp fermentation then you like this esters. Not tried the Sam Diego. My guess is it may not be as clean as you are expecting BUT some lager tray like 34/70 can be just as clean in the 60s instead of lager temps.
That probably wasn’t much help.

But you make a good point. If I like the beers that I have been producing without temperature control, then the esters produced (if any) must not be offensive to my palate. Since I am the one who drinks almost all of my beer, then I might be good to go. However, the San Diego Super Yeast is new to me - the batch ready to bottle is my first use of this yeast.
We’ll see what others might add.

 

[Josh Hughes]

Yep that’s what I meant. If you like it and always make it that way then you’ll probably be happy. One thing I’ve noticed is I’ll see fermenting temps for some of the big guys like Sierra Nevada, Stone, and tasting the esters in some of the English beers, are higher than what we are “supposed” to use

 

[Herm brews]

Thanks for your input Josh.

 

[Donoroto]

Yup, the biggest thing is some esters*, but maybe not so many or with much strength because you are not Way outside the range, nor are you seeing attenuation issues. I wouldn't worry about it too much.

That you like the beer is an added bonus!

*neither poly nor Aunt...

 

[FrostyBeach]

*neither poly nor Aunt...

Uff da Hey!

 

[GFHomebrew]

My memory of that yeast wad super clean super fast fermentations I used it at 18c.
If there isn't any offensive flavours your tasting then it sounds like you've found a great fermentation spot.

Recently I've been fermenting without temp control around 24c I've used pressure to try and combat the esters I think it's worked but can't wait to have temperature control again just for ease of mind.

 

[Herm brews]

I readily admit the shortcomings of my process, temperature control being the biggest. However, I am considering what could be done to implement temp control (a mini fridge is not among those considerations). An insulated box in which I could put a fermenter (or 2), along with some ice bottles might be the the ticket.

 

[Herm brews]

In any case, I have spun up a starter of WLP090 San Diego Super to use in my brew tomorrow. One good thing is that we will have cool stormy weather tomorrow, so at least Mother Nature will be helping.

 

[Mark Farrall]

...Given that this yeast performs best in the narrow range of 65F to 68F, what effects can I expect from a higher fermentation temperature...

The temp range printed on the pack is definitely what you'd prefer to use, but the yeast actually prefer somewhere a bit warmer, assuming they could offer an opinion. In warmer conditions they ferment faster and are less stressed. That faster fermentation will produce more of some materials and less of others. More yeast do tend to increase esters as they get warmer, but not all, and probably less than you expect and of course it also relies on gravity and pitch rate pretty heavily. Listening to a Master Brewers podcast on 34/70 recently and it was probably pitch rate that was more influential on creating esters than temperature, though gravity was the most influential.

I've brewed a bunch of batches with WLP090 and it's generally really clean. It's my preferred neutral ale yeast for imperial beers. I generally start it at the bottom of the recommended range and keep it in that range until about 50% attenuation. I will then let temperature move as it likes and push it just above the recommended range for the last 10-20% of fermentation. If there was a temperature effect, I doubt I could tell the difference in the beers I use it in, hoppy ales and dark imperials.

 

[HighVoltageMan!]

Excessive esters and high alcohols are the typical results of higher temperatures. Raising the temperature from 64F to 70F with WLP007 is very noticeable, but it will make beer. If you can’t lower your fermentation temperatures, switch yeasts. In your case I would recommend Lutra yeast.

https://www.northernbrewer.com/prod...19VOz-eY0kX5vkNLNrXh0QiTCPpsUHl8aAhoAEALw_wcB

The difference between an “okay” beer and a great beer may be as simple as a yeast change, choosing a yeast suitable to the purpose.

 

[Herm brews]

I love this site for the information. I posted a question, and I’m getting answers. Thanks to all for your informative feedback. Since I already have the starter going, it’s what I’m using. But I have food for thought. Feed me some more!

 

[Bubba Wade]

@Herm_brews Do you have a keezer? On one end of mine I have a chilled water reservoir with a submersible pump. This sends chilled water to a heat exchanger in the fermenter. Also, a couple of companies are selling a water jacket that wraps around the fermenter to cool via cool water circulation.

 

[Steve Ruch]

I'm currently drinking a pale ale fermented with BRY-97. The temperature got up to 76f and I don't taste any unusual esters or fusel alcohol. My previous batch was fermented with K-97 that got up to 74f, also no problem.

 

[Minbari]

@Herm_brews Do you have a keezer? On one end of mine I have a chilled water reservoir with a submersible pump. This sends chilled water to a heat exchanger in the fermenter. Also, a couple of companies are selling a water jacket that wraps around the fermenter to cool via cool water circulation.

This is a great way to go if you can get the water cool and keep it that way. I tried a small dorm fridge for this and just didn't work.
For $75 you can get the stainless coil to go inside. $20 fountain pump and previously mentioned stc1000 will do the whole thing for $100

 

[Megary]

I'm currently drinking a pale ale fermented with BRY-97. The temperature got up to 76f and I don't taste any unusual esters or fuel alcohol. My previous batch was fermented with K-97 that got up to 74f, also no problem.

I also use BRY-97 for my summer brewing because I don't bother much with temperature control. I usually pitch as cold as I can (low to mid 60's or so) and just let the fermenter sit in my conditioned basement. At high Krausen, I often get into the mid 70's and haven't ever noticed any ill effects.

 

[Herm brews]

@Herm_brews Do you have a keezer? On one end of mine I have a chilled water reservoir with a submersible pump. This sends chilled water to a heat exchanger in the fermenter. Also, a couple of companies are selling a water jacket that wraps around the fermenter to cool via cool water circulation.

No keezer, no mini fridge, and quite frankly, no room for any such implements - at least I don’t think there is room. I just put my fermenters (3-gallon size) in a tote in the under the stairwell closet. My wife says when we move to PNW and live in a house with a real garage, I can have whatever my brewery needs. Until then, I let it ride, or maybe look into that cooling jacket idea.

 

[Herm brews]

Good info, and interesting perspectives. So it seems the “ideal” temps for yeast might have some wiggle room. Except for sanitation, maybe there are no hard and fast rules in home brewing.