A tolerance of fart odour in lager

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Incongruent

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Made my first lager.... Everything is perfect except the smell. When cracked it smells a bit like farts. Although I've noticed commercial lagers also have a fart smell. In both cases I need to nose the glass before I can smell it. After 5 mins the smell is disappeared.

So how much fart smell in a lager is tolerable?
 
So how much fart smell in a lager is tolerable?

Depends on how thirsty I am.

It's probably hydrogen sulfide or other sulphur compounds that you're smelling, which often have rotten egg smell. One of the benefits of prolonged cold storage (lagering) of lagers is to help remove hydrogen sulfide. This is because lager yeasts and the relatively low fermentation temps are prone to more sulphur byproducts. So how long did you lager?

Other things that can help are make sure you have a strong boil and leave the lid off, yeast strain (some produce more of these aromas than others), and pitch enough yeast. Infection can also cause this so make sure sanitation is not an issue.
 
I had 4 weeks in primary at 9C. Another 6 weeks lagered in bottles at 2C.

I actually ended up mixing 11g W34 yeast with 11g mauribrew draught yeast because I realized I didn't have enough w34.
 
So how much fart smell in a lager is tolerable?

At the finished stage, none, or perhaps a small trace of sulfur. SO2 is a natural off-product of many lager fermentations. With proper lagering/aging it will be gone when the beer is ready for packaging.
 
So you're saying I should have transfered to secondary for lagering instead of lagering in bottles?
 
It could be that fermentation was not active enough to blow off the sulfur (9C is a touch low for many lager strains). Or, perhaps fermentation finished too soon and did not fully complete. You may consider increasing the ferm temp a few degrees, at least towards the middle to end of fermentation.

Also, it is possible that there is a bacteria infection. There are several bacteria strains that cause sulfur and rotten egg type smells. Most likely, it's the former, but just thought to mention it.
 
I've gotten lots of sulfur from WLP029 fermented at the lowest recommended range, as well as from W34/70 German lager yeast when I ferment it in the mid 50s.

My method to clear the sulfur smell is to degas it by turning up the temperature.
After my initial d-rest of 66 degrees, I hold it between 66-70 degrees for 4 days or so. The co2 coming out of solution "scrubs" the sulfur smell away with it. This is followed by a month or so of cold conditioning (standard for most beers I make).
 
So you're saying I should have transfered to secondary for lagering instead of lagering in bottles?

Bulk lagering before bottling or kegging does seem to be the standard wisdom, although I've never lagered in bottles. The last lager I made had a sulfur smell when i racked from primary to secondary to lager for 6 weeks - at which point the sulfur aroma had disappeared.
 
The sulphur aroma is becoming weaker. I think it will be fine in a couple more weeks.or else I'm going nose blind.
 
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