Temperature control

[poppalarge]

Hello.

I'm in the UK and I finished my second batch yesterday, an extract version of the Sierra Nevada clone.

I did the second lot as soon as the first went into bottles. Since my first was a Coopers lager with added 'brewing sugar' and I'm not holding out much hope for it. Despite my dry hopping with some goldings hops.


Anyway my question is about temperature control. How important is it?

My house goes from 18-22 degrees C at this time if year. I imagine it will get cooler as the winter draws in. Is that an acceptable range or am I asking for trouble?

 

[Obliviousbrew]

18-22 C is pretty decent how much cooler does your house gets?

 

[poppalarge]

Probably down to 16 at its coldest.

 

[Obliviousbrew]

Maybe one of those heating brew belts will help you. Ever think about an old fridge with an external temp control to make sure that you are hitting your temps correctly? vigourous fermentation can take you a couple of degrees up from ambient temp. At 16 some yeast wont work very well but it´s acceptable anyway.

 

[Kahless]

A consistent temperature is good - rapid changes can upset yeast and lead to off flavours. It's also good to be able to repeat what you do and get reliable results, e.g. at higher temperatures you can end up with fruity esters and other odd flavours, and you might not mind just a few in one brew, but in another brew you might want something "cleaner". The yeast strain will also come into play here; some are more likely to do this, some are more tolerant than others; know your yeasts happy range so you can adjust conditions if it is getting too odd.

My first brew coincided with a Heatwave over Glasgow that lasted a week or two - Beer at 25/26 degrees Celcius - It smelled like cider at first, and then ended up having a solvent/sugar taste with a strong bitter aftertaste, and zero head retention (It was coopers dark ale, but ended up looking like coca cola).

As long as the yeast gets a grip on the beer (rehydrating dry yeast should help), and fermentation gets under way then it is fine (I use hydrometer readings and recipe software websites like beer-calculus to give me an indication of what my gravities should be). It's normally better to be on the cool side of the temperature scale to avoid off flavours, so if fermentation not happening would be the main thing to look out for, and that's easy enough to look out for.

For these reasons I would not sit beer near a heater or radiator, and would instead begin with bubble wrap and tinfoil, jumpers for winter (fermentation is exothermic so keep some heat in if its cold), and have a look at the temperature as the batch progresses.

For one gallon batches I've got a bucket of water to sit the demijohn in, and an aquarium heater which keeps the water (and homebrew) at 20 degrees C (although i set it a degree higher to get the water to be safely above 20). If there is no risk of extra warm days spoiling things then this could be a solution for you (bigger bucket, or a plastic bin!). If it becomes challenging to keep temperatures in the right zone. Monitor room temps at night and during the day in your brew space and see if it's necessary - I have to do this to brew at home but my partner lives in a flat and as it is sandwhiched by other flats with their own heating etc then her room stays about 21-23 degrees (apart from during the heat waves!)