Toffee tastes in my first AGs

johnnie · May 22, 2012

I've done four AGs now, all from the Wheeler book.
Youngs Special
Hop Back Summer Lightning
Pendle Witches brew
and Camerons Strongarm.
The Strongarm is still fermenting. I've noticed that the other brews have tasted great at the bottling stage, but after conditioning they've got a strange underlining taste. I can only describe it as sweet toffee or caramel. Anyone any ideas on what is causing these tastes? However I must say that going AG has given a better brew even with the toffee taste.

Sean_Mc · May 23, 2012

Sounds like Diacetyl, have a read HERE J

orlando · May 23, 2012

It can occur if bottling/kegging too soon, before the yeast has had a chance to "clear up" after itself. Charlie Bamforth was intervied on BeerSmith's You Tube channel and suggested raising the temperature of the ferment a few days in to help with dealing with the precursors to diacetyl. This is something I do as routine now, fermentation is exothermic and will rise in temperature naturally but as it starts to come down this is when you "artificially" raise it. I appreciate if you haven't got the facility to do this this advice is superfluous but by leaving the brew to continue fermenting (even though there may be no signs of it doing it) you will go along way to eliminating this fault.

johnnie · May 23, 2012

Thanks guys. I do tend to bottle pretty quickly as I'm always worried about getting an infection. I'll try leaving them longer in future and see if that helps.

orlando · May 24, 2012

This is an understandable reaction as most faults come from infections but the thing you have on your side after fermentation and of course even the latter stages, is that alcohol and hops are a powerful ally in keeping them at bay. You will get more problems with aerating the beer during transfer than airborne bacteria, though the summer months do pose more risk.

johnnie · May 24, 2012

Thanks again Orlando. Are AG brews more prone to this problem? I've done 4 extracts prior to going AG and didn't have any off tastes. Although I think I could still taste a slight homebrew tang with the extracts.

orlando · May 24, 2012

That's a good question and to be honest I don't know. If it is I can't be sure why because this is for the most part a problem with fermentation profiles, unless the wort constituents themselves make it more or less likely. With AG brews there is a lot more variability becuse of the yeast used, which can vary in quality because of the many ways in which AG brewers end up with their yeast. With kits the yeast is presumably designed to brew that wort with more predictable outcomes. What I can say is that if you follow the advice and allow the fermentation to go beyond say 10 days and you don't get any more problems, you have a very large clue.