I’m trying to get serious about brewing lagers this winter. The first was a G. Pils with the Wyeast 2124 Bohemian Lager. I pitched 2 packs into a 2 L stirred starter for a 6 gallon batch. The primary fermentation as at 51 F and was active within 24 hours. Around day 6 I noticed that it was producing a fair amount of sulfur. By day 8 it was basically done fermenting and I ramped the temperature slowly up to 60 for a diacetyl rest and to ensure complete fermentation. I left it there for a week and moved to a keg to lager. There is still some sulfur evident in the samples I’ve taken after another 2 weeks.
I’d love some input on the following:
What could I have do to prevent this level of sulfur production? Nutrient? More O2? Is this common with this yeast strain?
Has anyone ever used CuSO4 to deal with sulfur in a beer? I’ve used it in wine with great results but I can’t find anything about using it in beer. I was thinking of doing some bench trials to see what the effect is.
I’m assuming you had a grist bill which was predominantly pils malt…? If so did you boil hard for 90 min? I always boils at least 90 min to drive off the DMS precursors that are prevalent in pils…Did you cool the wort fairly quickly? Being slow to cool can cause the precursors to amass once again.
Other than that, most lager yeasts give off a sulfur aroma and, after some conditioning and a lagering period the aroma diminishes significantly.
Sulfur tends to be produced by “unhappy” yeast in my experience. It could be Oxygen, nutrients, or something else. The good thing about sulfur is it tends to dissipate over time. So I wouldn’t worry just yet. It’s not the production of sulfur you need to worry about (lager yeasts will tend to do this) but sulfur in the finished beers.
My lagers usually take a few weeks to finish, I’m surprised yours was done after 8 days.
I was a bit surprised at the fermentation rate too b/c my few previous lagers have fermented too slowly and I ended up increasing the temperature. However, it wasn’t a big beer and I pitched a really big healthy amount of yeast. I was really feeling good about myself until the room started to stink!
I know in wine making we do staggered nutrient additions to decrease sulfur production, typically at the 1/3 and 2/3 sugar breaks of fermentation. I think some meadmakers advocate doing this as well. I might try that for my next lager.
Sulfur is a good thing in lager production. If you’re smelling it, then it’s not staying in the beer, which is exactly what you want. Do not use copper sulfate to deal with it. The relatively low levels that lager strains put out can be dealt with by simply leaving the beer in contact with the yeast for an adequate amount of time.
