Constant fermentation temps

Mal1841

I'm just about to start my 4rth batch of beer. This time I'm doing a young's American Amber Ale "AAA" I've had some problems in the past with.....well home brewy tastes to my finished beer and I'm hoping to eliminate that this time round. I've purchased a premium yeast for this kit, not the supplied one and I'm trying to get to grips with a constant fermentation temp.

Now heres the problem. In my house there isn't a room that has a constant temp throughout the day. The central heatings on a thermostat but it goes off during the day when were at work and at night when were in bed which fluctuates the wort by about 2 degrees Celsius. My past kits say to ferment between 18 & 22 degrees but this yeast says optimum temp is 20-25 degrees. I have a heat pad which i bought on here but no way of knowing what temp that keeps a 5 gallon bucket at. I read its always best to ferment on the lower end of the scale so will a fluctuation of 2-3 degrees throughout the day make flavour changes even if its within the optimal temp range for the yeast?.

Is there some sort of equipment I can buy that'll heat/cool the wort using a thermostat ?. My end wort is never as strong as it says on the box either. Even after 5 or six days extra than the instructions say it always seems to be about 2% weaker. Do you think this is to do with the temp in the house throughout the day?, and the home brew flavour do you think its from the wort sitting on the dead yeast the extra time from me trying to get it up to the proper ABV ?.

Sorry so many questions!

HBO_Staff

You're in a common situation here, most people's homes fluctuate in temperature so it can be difficult to keep the temperature constant, a heater tray will keep a full vessel approximately 8 or 9 degrees above the ambient room temperature, so it can vary. There is not that much you can do to stop this, although the temperature of the liquid will only change very slowly due to the relatively large volume of it - any changes are slow and happen over a few hours. If possible find somewhere out of the way where the temperature is quite steady, away from draughts etc, and use an LCD thermometer or similar to keep an eye on the temperature from time to time, a couple of degrees either way is very common and should not harm the brew. Off tastes can be produced if the temperature gets very warm, it is best to be at the lower end of the temperature range rather than the upper.

Currently there is no device that will hold a steady temperature, although watch out for our latest newsletter as this may be about to change, we might have the solution there. There are no devices that are mass produced which will cool the brew, so in summer if it ever gets really warm there is not much that can easily be done to keep the temperature down, but most brews will turn out perfectly fine.

The alcohol strength is determined by the amount of sugars present in the brew, once the fermentation is complete it will not go any lower, a hydrometer reading once down as low as it will go means the sugar has fermented, and this is as strong as it will be, although one thing to bear in mind is the priming sugar will also ferment and add a little extra once it has secondary fermented. The American beer range has quite a strong alcohol strength, if however on other brews you wanted to increase it then add a little more sugar and reduce the volume of water slightly, as a general rule though if you make the brew to the volume the recipe says and use the ingredients it recommends, the strength will turn out around what the manufacturers state, they have tested it and ensure there are no reading errors etc. so are a very good guide. If you leave the brew on the dead yeast for a while after fermentation is complete this could impart flavours into the brew, many people leave it a few days extra before bottling, say until the next weekend when it is more convenient, and a short amount of time wont usually have any bad effect

Mal1841

Thanks for that. This yeast I bought says prime temps is 20-25 degrees Celsius which is higher than the other yeasts ive used. I have just bought an immersion heater from here and I plan on setting it to 21. I know it wont go higher than that in the ambient room temp so hopefully this will keep it at a constant temp. I shall let you know what happens with the hydrometer readings in a week or so's time.

M

Mal1841

Hmm I don't think the immersion heater I bought here is working.

I started brewing last Friday and before I did I tested the heater in the fermenting bucket full of water. I set the thermostat to 18 degrees as the yeast I'm using says optimal temp is between 15 and 20 degrees. The light came on and heated the bucket to 18. I made my beer, pitched the yeast putting the lid on the bucket with the heater attached. I went away for the weekend and came back yesterday to find the vigorous initial fermentation had happened and all the foam and scum had died down and almost disappeared. The thermometer was reading 14 degrees. I cant really take it out just yet to have a look in case i infect my brew.....I dont even know if the yeast is active cause I have no idea how far the temp dropped to during the weekend.

Any suggestions you might have ???

M

HBO_Staff

If the Immersion heater is set at 18 and it is keeping it cooler than set at then that it would suggest a problem with it, the temperature can eb affected by things such as if being used in direct sunlight, near a heat source (such as a radiator) or somewhere positioned in a draught which can all alter the temperature that is being monitored. The froth and scum show that the initial fermentation has started and that it is fermenting, it will be a case of checking the hydrometer reading nearing the end of the expected fermentation time to establish when it has totally stopped. Once complete it can then be bottled or barrelled. If you believe the immersion is not working correctly and is not keeping the temperature correctly, it would be worth checking if it is lighting up and whether or not it is getting warm, and if not then checking the fuse to rule out that as the reason, but in the case of a fault please drop us an email and we will sort out for you as it may need returning to the manufacturers for testing, just let us know

Mal1841

Will do thanks

Mal1841

So it turns out the reason the heater wasn't working was because my wife had unplugged the extension cable to the heater to charge her laptop and never plugged it back in!!. ( both have black plugs and she left her laptop cable plugged in!)
Luckily it was a mild weekend & looking at the wort tonight it looks like it's doing a gentle rolling boil at 15 degrees. I assume that's good :0)

HBO_Staff

Well that would explain it! A cooler ferment is no bad thing and can produce some great flavours, the fermentation speed will slow down as it gets cooler but as long as it keeps fermenting until the hydrometer reading is nice and low there will be no problem