does temperature make a difference

[rawsondsr]

on speed, obviously, yes.
hotter=faster
colder=slower
really cold=stopped?
really hot=dead yeast?

on taste?
hotter?
colder?

 

[anthonyUK]

Hi,
This is a big contentious topic.
I would do some research as there are plenty of posts regarding yeast and temperature control but basically try to keep the temperature close to the middle of the yeast recommended temps.

 

[graysalchemy]

In ale and lager yeasts yes it makes a lot of difference to the taste of the beer, especially in the initial stages of fermentation, which unfortunately can be the hardest to get under control.

When yeast are multiplying they can take various metabolic pathways. One of which is the precursors of esters the group of chemicals which can give beer a fruity aroma. This can be beneficial in ales but not lagers and increases in production up to about 21c. After this metabolism switches to produce the precusors of fusel alcohols. These are the ones which give beer a hot solventy flavour and are definitely not desirable in beer (though they are evidently in Brandy).

So if you brew at lower temps then you will not get the fruity esters and this will allow the malt and hops to shine through.

As I said this happens very early on in the first 24-48 hrs, so it is crucial to keep an eye on temps.

As a general rule try keeping your wort at around 18-21 if using an ale yeast. Lager needs to be kept cooler and belgians well they have a completely different set of rules :lol: :lol: .

 

[Duxuk]

Yeast will ferment your wort most quickly at around 35C, depending on the strain of yeast. At these temperatures, though, you will produce other alcohols than ethanol. The beer is likely to have an offensive chemical/ alcohol taste and may give you a serious headache.
18-22C is normally considered good for ales with 25C or over as the no mans land where you should never venture because you will produce these fusal alcohols.
For a lager yeast you need to keep it much cooler. This is how you get that crisp lager flavour. Many lager kits come with an ale yeast anyway, to avoid the neccessity of temperature control.

That's just a brief overview!

 

[mike77]

25C or over as the no mans land where you should never venture because you will produce these fusal alcohols.

In most circumstances I would agree however I used two yeasts over 25c this summer without any problems. WLP644 Brett Bruxellensis Trois and Mangrove Jacks workhorse yeast.

I personally would stick within the temp range that the yeast manufactures specified. If they say max 21c then I wouldn't go over that, if they say max 30c then I wouldn't have a problem with brewing at higher temps.

 

[graysalchemy]

In most circumstances I would agree however I used two yeasts over 25c this summer without any problems. WLP644 Brett Bruxellensis Trois and Mangrove Jacks workhorse yeast.

Was that the temps in the first 24-48 hrs or after? as i said it is the initial stages where damage is done. Though WLP644 Brett Bruxellensis Trois is a Brett and not a Saccharomyces yeast and as I said before Belgians have different rules :lol:

I personally wouldn't ferment any ale or lager yeast over 21c especially in the initial stages. It only takes a low leval of Fusels to ruin a beer, as they are detected by humans at very low concentrations.

 

[mike77]

Was that the temps in the first 24-48 hrs or after

I get my temp down as far as I can with an immersion chiller. When I was brewing those beers I recall 23 being the lowest I could get it. Once the yeast is pitched I just leave it at ambient temp. The Brett brewed right up to the high 20's while the Mangrove was probably about 26c.

 

[graysalchemy]

I have certainly had fusels in a bitter where the temp rose to 22c in the first 24 hrs before I got control of it. It is not a pleasant taste and never really goes. :evil:

 

[SamT]

Near in mind that Saison yeasts can be pushed to remarkably high temperatures - 30C isn't unheard of to get maximal ester production

 

[zgoda]

Not all saison yeast requires this, Wyeast 3711 gives perfect results in 24c or so. The ramp up to 29c is sometimes required to get full attenuation, but French Saison don't need this.

 

[graysalchemy]

i agree traditional saison yeasts work between 18-24c though the Dupont brewery yeast is used upto 30c and most american saison yeasts are similar.

 

[Andytash]

I have a problem !! No not that one. I live in the tropics and struggle to keep my temperature in any sort of reasonable range. Has anyone here managed to fabricate some sort of wort chiller or the like than can be used to keep the f.v. cool? Everything back in blighty seems to be geared to keeping it warm.

 

[graysalchemy]

Lack of refrigeration was the reason why India Pale Ale was shipped half way around the world. Once refrigeration was invented and the germans erported the technique of lagering then IPA declined.

Plenty of us rig op fridges and heaters controlled by a STC 1000 which controls both heat and refrigeration. Some of us (especially those whose Fv won't fit in a fridge) use a Maxi 310 beer chiller. These usually have a product chiller were a beer line goes though and a pump closed loop used to pump cold fluid through a heat exchanger which in my case is a 10m coil of 10mm copper which is suspended in the FV. With this set up i can pretty much keep my beer on temp. My temp controller is set at 20c and and the beer has been constant in the range of 20-20.5 since fermentation started 24 hrs ago. :thumb: :thumb:.

The fv is in an insulated cupboard with a small tube heater in it also. :thumb:

 

[Andytash]

Thanks for that - I shall investigate further.

Andy