I get sulphur on lagers sometimes. It goes away. It happens from time to time. You’re not doing anything wrong except getting frustrated. RDWHAHB.

 

Great story Matt, sounds like you got a real keeper of a wife there

 

Relax, don't worry, be careful you don't have too many.

 

I've had issues with maris otter completing conversion in the usual timeframe of 60 minutes (even at low pH levels) and have had to extend the mash to 90 minutes or longer. Maybe an incomplete conversion, combined with the higher pH levels, created a difficult environment for the yeast and as a result it stressed the yeast and/or precipitated a byproduct that resulted in a sulfur essence. At least it fades.

If you're feeling frisky, see what happens when you reduce the % of MO at your previous pH levels and mash duration. Since the sulfur doesn't persist, there's really no downside.

 

Sulphur is almost always related to the yeast/ fermentation. I can't image the pH of the wort would cause a sulphur problem, but getting pH under control is pretty important overall anyway. Ales can and do produce sulphur, but at a much lower rate than lagers. There's something going on with the fermentation causing it, but nothing really seems to be outside the norm in your description. 20C fermentation temp can be a bit high if your using a plastic bucket to ferment, since it traps more heat from the exothermic effect from the yeast. Dropping the temp will improve the beer overall, but I don't think that would cause or solve a sulphur problem. Metabisulfite, maybe if you used to de-chlorinate?

Huh, that is weird.

 

The correlation between the mash pH and sulfur is new to me, I'm assuming the higher the pH the more likely the compound would be found in beer. The link is "forbidden", so I couldn't read the page you referenced, but it may very well be the case. I guess that's another good reason to keep the mash pH in check. It makes for better beer anyway.

As far as the fermentation temp of US05, when I do use it, I keep the temperature pretty low 15-17C or 60-63F. I have found this yeast and most yeast I use, make much better beer when fermented lower. US05 can go as low as 12-13C. I don't use that yeast much anymore because it's a fairly low acid producer and the pH in the finish beer is a little high, @4.5 or so. Other yeasts will drop the pH to 3.9-4.2 in the finished beer and makes for a crisper, smoother beer. One of my favorite subs for US05 (Chico strains) is Wyeast 1007 German Alt yeast. That yeast can go done to 52F (11C) and it's a great acid producer, but it can produce sulfur, although it's never been a problem.

 

I put my beer in my laundry room that maintains a pretty consistent 18-20C all the time and have never had a bad batch yet, I use BRY-97 a lot which the the Danstar version of US05 so I don't think that should be a problem.

 

Haven't heard of a link between mash pH and sulfur.... Yeast strains, particularly lagers, yes, but not pH.

 

You won't necessarily have a bad beer, it just a preference. I prefer the lower temp beers due to lower yeast character. I don't think fermenting at that temp will produce sulfur, there is something else going on with the yeast to produce that odor.