wort temperature when fermenting during warm weather

Tom_B

I started an extract brew yesterday evening and because I steeped some malt the wort started off at 26 deg and is still at 22 deg this morning - so my questions are - is it ok just to leave the wort to cool down for a day? and when it gets warm in the summer do I need to have a strategy for keeping the wort cool?

HBO_Staff

Hi Tom_B, when home brewing it can sometimes be a little tricky to control the temperature, especially in hotter weather so all you can do is your best. There are a couple of things to bear in mind, firstly the temperature when you add the yeast - the brew temperature needs to be in the region the yeast works within, usually given on the instructions or on the yeast if you have upgraded the yeast or bought this separately. If it is too hot then the yeast may be killed off, so try to get the brew as close to the recommended temperature as you can before pitching the yeast.

Secondly, timing - once you mix up the brew and it is ready to add the yeast, ideally you need to pitch the yeast as soon as possible. When no yeast is added, this is when the brew is at a higher risk of infection or contamination, once you pitch the yeast and it starts to ferment, this gives the brew some degree of protection. For this reason ideally you need to get the brew at a good temperature to add the yeast as quickly as you can. When brewing with all grain and the malt has been mashed and boiled, it is usually cooled down quickly by using a wort chiller, so you can get the brew temperature right down and add the yeast shortly afterwards.

If you are finding your brew is too hot, you can improvise and use cold water or ice etc, around the vessel to cool it down faster if needed.

During hot weather all you can often do is to do your best and try to brew in as cooler room as possible, some people who are really into their home brewing adapt old fridges to brew inside, and use a temperature controller to keep a steady and pre-set temperature for the fermentation, this helps to produce consistently good beers and lagers.

A guide is here with a little more info on fermentation if of any interest:

https://homebrewonline.vanillacommunity.com/discussion/519/fermentation-what-to-expect#latest

Tom_B

thanks - that's really helpful. I'll start looking out for a freezer to modify

HBO_Staff

They can be really useful to maintain a steady temperature, and ensure consistent brewing results, here is a link to an article on the forum of a great fermenting fridge another member made if of any interest (scroll to top of page on the link):

https://homebrewonline.vanillacommunity.com/discussion/1108/fermenting-fridge#latest