Disadvantages of brewing at a lower temp

[arturobandini]

Morning all,

I've got my first brew kit on the go in my front room and by all the signs (big foamy crust, nice bubbling.....my front room smells like a brewery....). My flat isn't the warmest place in the world so i'm worried about the temperatures. I've no thermometer as yet, which is next on my list of items to pick up, so I don't really know what temperature it is going at. I've read a lot about temperatures that are too high releasing fusel alcohols making for a glue sniffers dream brew but what are the risks of brewing at slightly lower than 20c? Aside from the obvious yeast dormancy risk does it actually make the yeast less effective ie: Produces less alcohol as a result of the lower living temp? Taking longer to ferment have an adverse effect to the brew itself?

Perhaps I'm being overly concerned with it being my first kit. I've wrapped it up in a large towel to try and lock in any warmth given by the chemical reactions going on in the vat. The kit is a double measure of Brewferm Diabolo to make 18 litres of hopefully lovely golden ale. Any help as always greatly appreciated. I'd probably have whipped up 18l of cider vinegar by now if it hadn't been for some solid research on Jim's excellent site.

Cheers

[Garth]

I wouldn't worry, most ale yeasts will tolerate down to 16C probably lower, but this will obviously slow things down. It's always better to have a little higher temp of the wort when you pitch, say 22-24, then once it's going let it drop a bit.

Nottingham, a good clean ale yeast has an optimum operating temperature of 17C and S-04 likes it around 18C. The cooler side of things make a cleaner tasting beer. I suppose that's why Lagers are fermented really cool (2-12C) and they are usually very clean and crisp. But anymore than 25-26 and you risk making those fusels you talk about.

my kitchen goes down to 16-17 on a night sometimes during the cold nights and my beer always ferments out right without any majorly dodgy tastes. I use S-04, Nottingham and US-05.

[Madbrewer]

I find that one room without a radiator (if you can spare an unheated room) keeps the ale fermentation very well October - April. 18c is ideal 3degrees either way wont cause a problem though! Although it takes longer to ferment the clean tasting beer is worth it IMO

Without a thermometer maybe you need to imagine the temperature of a bedroom, where the temperature would be just right if you were in bed & under the covers - therefore cooler than a room heated to allow you to just wear a T shirt, not freezing cold either though

[arturobandini]

Excellent guys thanks for the speedy and informed responses. I can't say how glad I am that I found this forum before I launched headlong into the homebrewing world. Going off what you gents are saying then my front room seems to be around a good temperature for brewing, i'll find out more when I jog down to the Home Brew shop a bit later on to see if I can grab a thermometer. I think they're definitely useful for pitching temps etc and worth knowing how things are as the brew progresses I would've thought.

Like I said it's just probably my first brew nerves and over-protectiveness as everything smells,sounds and looks great.

Thanks again

[Mitchamitri]

I make cider and that ferments cold cold cold - even when brewing beer though i always consider taht too hot is less recoverable than too cool.

Just one tip - when you measure temperature make sure you measure the temp of the liquid not the temp of the room.