Fermentation Appears Finished at Day3

[Coedbach]

I used to brew my own beer back in my late teens but as the price of beer is getting ridiculous and looking for a nice hobby decided to dabble once more but still very much a novice.

I thought I would start with the basics. I've got a 23L fermentation bucket from MYO (The Range) and have Young's Harvest Stout with included yeast, 500g Sugar, 500g Dark Spraymalt and 500g of soft brown sugar and I'm currently at the end of day 3 (84 Hours) and the fermentation has slowed right down. So I took a gravity reading and it read 1.012.

The fermentation was very vigorous, I began at 6am (I work nights) and used a heating pad around the bucket to maintain temp. By 2pm the same day the temp had risen to 27°C and stayed there even after removing the heat.

Tonight the temp had dropped to the more normal 23°C but there is hardly any off gassing through the airlock.

Have I made a complete pigs ear of it? It seems excessively fast to me to be done in 3.5 days. The can said 5-10 days and reading this forum and Facebook groups I've joined recommend 2 weeks.

Any advice greatly appreciated.

TYIA

 

[RM-MN]

Read through this article. It explains a lot.

http://www.brewgeeks.com/the-life-cycle-of-yeast.html

 

[Coedbach]

Read through this article. It explains a lot.

http://www.brewgeeks.com/the-life-cycle-of-yeast.html

Great source. Much appreciated

 

[worlddivides]

A lot of British ale yeasts start fermentation pretty quickly and finish it quickly as well. The higher the temperature, the faster and more vigorous fermentation goes, but that also carries the risk of off-flavors (esters, fusel alcohols, and so on) being produced. At what temperatures these are produced differ from yeast strain to yeast strain, but 27C will generally create a lot of off-flavors in most English yeasts. Most of the English yeast strains I've used have an ideal temperature range of 15C to 20C with 17-18C being the ideal usually.

As the link RM-MN posted says, though, just because airlock activity is done doesn't mean the yeast are done. They also spend time cleaning up the beer by consuming undesirable compounds such as diacetyl (a butter-like flavor that is not wanted in the vast majority of beer styles). So even if you've reached your final gravity already, that doesn't mean the beer is ready to be packaged.

 

[marc1]

What resources suggested a heating pad for higher temperature fermentation? You may want to reevaluate reliance on that source.
Unless the environment is very cold, beer generally benefits from cooling rather than heating at the beginning of fermentation.

 

[keystonehb]

What resources suggested a heating pad for higher temperature fermentation? You may want to reevaluate reliance on that source.
Unless the environment is very cold, beer generally benefits from cooling rather than heating at the beginning of fermentation.

This is important. Using a heating pad is a good idea, but you have to make sure you only use it when you "need to" If you're fermenting above 70F (21C) you should not use it unless you're using a strain meant to ferment higher.

 

[Coedbach]

What resources suggested a heating pad for higher temperature fermentation? You may want to reevaluate reliance on that source.
Unless the environment is very cold, beer generally benefits from cooling rather than heating at the beginning of fermentation.

Recommended 20-25°C for the yeast supplied. I wasn't going to get that temp in January in the UK without a heating pad.

 

[marc1]

Recommended 20-25°C for the yeast supplied. I wasn't going to get that temp in January in the UK without a heating pad.

Were you measuring beer temperature or ambient? Did it say what specific yeast it was? 20 seems great. 25 seems pretty high.

What is the temp where you are fermenting? Is it in some kind of fermentation chamber, or just in a room?

At this point the beer is going to be whatever it's going to be, so don't worry about it. Let it finish out, and enjoy it! Fermenting on the lower end of that range will probably give better beer results of you do it again. You could even make another batch to compare

 

[mac_1103]

Recommended 20-25°C for the yeast supplied

Instructions actually say to pitch at 20-25C and ferment at 18-24C.

 

[keystonehb]

Instructions actually say to pitch at 20-25C and ferment at 18-24C.

Pitching the yeast slightly warmer than desired temps pretty much help the yeast kickstart the fermentation process, but you dont want to be too much warmer. After the initial pitch period you usually want to be in the mid-low end of that temp unless the yeast gives off desired esters or phenols that you are looking for.