Fermenter Temperature

[StuBear]

Greetings AHB,

Thanks for a very infomative site!

I've recently returned to Australia after a long stint in Japan and have started homebrewing. I'm living in Melbourne and am wondering what the best option is with Melbourne's up-down weather.

Should I aim at keeping the fermenter below 20C (as most of the post I've read recommend) even if that means that on cool nights it might drop below 18C? I'm yet to get a beer fridge and was looking at the 100 can coolers, but they are only 45cm high and my fermenter (30L) is 52cm. Recently I've been wrapping the fermenter in bubble-wrap (which I have heaps of) and put ice-packs on the top for hotter days, but am concerned that the cool changes might drop the temperature too low overnight or while I'm out and can't remove the ice-pack.

Any tips would be appreciated

thanks

Stu

 

[arsenewenger]

Stu


Welcome to AHB

as far as my knowledge goes leaving the ice on overnight or when you are out making the temp drop lower than 18c will only slow the fermentation down to maybe take a day or two longer before you either rack and cc or bottle , but letting the temp get to high can result in off and or fruity flavours in your beers and if it goes too high killing it all together. IMO I would rahter worry about it getting to hot before getting to cold .

Hope that helps somewhat .

Cheers
AW :beer:

 

[DJR]

Welcome to AHB.

I wouldn't worry about it, you can take the ice out overnight but even if you don't the temperature won't drop enough to stop the fermentation. The fermenting wort usually has enough thermal mass to stop ambient temperature changes making a huge difference to the temperature. I'd only worry about it if you had freezing temps at night.

And it won't matter if you fermenter doesn't fit perfectly in a cooler, any insulation is good insulation. You could get one and then just put bubble wrap or camping mat around the top exposed section but i doubt a 10cm exposure will affect the flow of heat very much.

 

[The Scientist]

Welcome StuBear,

This is what I use for my Ales, it is just made out of sheets of foam and glued / taped together. It works a treat and seems to keep an ambiant temp that is about the average of the dayly high / low temp of its location. So it has been staying around 22C with only a +/- fluctuation of about 1-2 deg.



Cheep yet effective B)

Cheers,

TS

 

[Kai]

Too hot will screw the beer up, too cold just makes the yeast slow down or go to sleep. However, later on in the ferment you might run the risk of the yeast not waking up at all. My usual fermentation regime is to keep it cool while the yeast is actively fermenting, and warm it up a little when the last few points are being ticked off.

 

[StuBear]

Thanks guys,

I'll work on keeping the temp around 18-20 and won't sweat ti too much if it drops a tad below. I'm willing to wait a day or too extra to bottle, better that than a bad brew

I've been dropping som fruit and veg shops to try and get some polystyrene boxes, but it seems nobody uses them anymore.

I've got a couple of camping mats, I'll have a play with them and see what I can do might be able to line some cardboard boxes with them

thanks again

Stu

 

[Fingerlickin_B]

I use something similar to The Scientist too.

Mine is an old bathroom vanity unit with the sink removed and top hole cut out larger using a mate's jigsaw.

Sheets of polystyrene are glued to the inner walls and doors.

Access to the fermenters (it fits 2 inside) is through the top hole (covered by a hard-backed Mr T poster when in use :lol: ).

As for the foam, contact a place that manufactures cool rooms. I got two sheets for about $9 each and only ended up needing half a sheet, so its a pretty cheap exercise

It's even fitted with a 40w light bulb for winter (after fermentation slows down...to keep the yeast awake).

You could get the vanity from your local rubbish tip recyclers or building recycler for bugger-all too :super:

PZ.

 

[StuBear]

Thanks ofr the heads up on the foam supplier, I'll go through the yellow pages and see if I can score any.

Stu

 

[Mekeman]

Hiya all, my second post,yeha. Anyways, I thought that if the temp drops to low the yeast would die, same as if if went above 32 degree's. As I have brewed through the last few summers up here on the Goldy, I find that my worts can be bottled after about 6 days during summer and some of those days the temp hits maybe 32 plus. The beers seem to be nice to drink but then again it is summer,lol.

 

[mika]

Yeast generally doesn't die...unless you freeze it, then I'm not sure.
An ale yeast (as supplied in most kits) will brew happily t 18deg, I've had the Coopers yeast still bubbling at 16deg. Below 14deg and it might start to snooze...but then as soon as it warms up again the yeast will wake up and start chewing thru the sugar. Can be a problem if you've thought it's finished and bottled the damn thing (experience).
Lager yeasts are best at 9-12deg or below and I'm pretty sure they'll still be going right up to the point where your brew goes solid.
The cold is you friend...brew lots in winter

 

[RobboMC]

When I brewed at ambient temps I found the best method was to put the fermenter in the shower recess. The bricks and tiles of the bathroom assist in insulating from outdoor temp extremes. A block of ice on top during the day was enough to keep it cool. At night just leave it dry, unless it's like 30 degrees. Usually a single day at 30 deg isn't enough to raise the wort temp much. Bubble wrap was a great idea, air is a great insulator, keep up that sort of thinking.
Another idea is to put the fermenter in a tub of water and drape a towel over it. The towel acts like the wick of a candle, drawing the water up, and then it evaproates. Works just like an evaporative air conditioner, that evaporating water really sucks up an awful lot of heat. I find spring and autumn are the best brewing months as the ambient temps are more constant. A simple solution to your problem is to buy more bottles and run the fermenter continuously during these seasons and not brew in summer. I did a brew last january when it was 47 deg in Sydney and even in the fridge it got too hot.

I managed to pick up and old fridge from a workmate, and I brew and store in that through the summer. If you are keen to maintain constant brewing temps that is the best way, even if the fridge is left switched off as I have this week, the insulated walls slow down all the heat movements and allow you to maintain a very even constant temperture in the wort.

 

[StuBear]

Well the bubble wrap and the camping mat seem to be doing the trick at the moment.
The stick-on thermometer has been between 18-20C for the last 4 days (dropped down to start highlighting 16 from 18 on the coldest morning).

Can't put it in the shower, the wife would have kittens , got it in the shed at the moment and the shed is protected from the afternoon sun and is always cooler than house.

I've joined freecycle and am keeping a look out for a fridge to store things in, think that will be the easiest at present.

thanks for all the suggestions

Stu

 

[kitkat]

I'm in Melbourne and have no specialised insulation or modified bathroom fixture. I just leave my fermenters outside.
In winter I brew pils/lagers, they take about 2 weeks to ferment. No big issue with temp as it seldom gets above 15 degrees anyway.
For Ales/wheats, I brew in spring and autumn, when there are periods of 16-22 degrees. I then leave the fermenter in a shady spot so that even if the air gets to 22/24 the fermenter is not in the sun and hence would not get as warm.
And in summer, well, I drink ...
I'm the only one drinking my homebrew, so as long as I have 4-5 pils/lagers and 2-3 ales before summer I'm right Then when autumn comes (again those 16-24 temps) I make a few dark ales for winter