Pressure Fermentation/Strong Sulphur Smell

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Crafty

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Hi All,

New member and first post so apologies if its been covered before.

I've been brewing for about 9 months, only using kits and was just about to make the jump to all grain when I ran into a few issues with off smells/flavours.

I've been pressure fermenting using the keg King chubby and had a about 5 successful brews, the last too have been disposed off unfortunately due to very and I mean very strong sulphur smells and the beer tasting similar to how it smelt.

I have been attaching the spunding valve and set this to about 5psi from the very beginning straight after pitching the yeast, around the 3-4 day mark is when the sulphur smell hits. I've been wondering if this could be stressed yeast, doesn't explain why I had a few successful ones all done in the same way but ambient temperature has been high now we are in summer so I could have just about got away with it before and now being slightly warmer too has pushed it over the edge!

I've ruled out sanitation issue as I've got a successful brew going now using all the same equipment cleaned in the same way, the only difference really is I'm using an airlock, no pressure no spunding valve etc. Hence suspecting pressure to be the issue .

Any help or advice would be greatly appreciated.
 
Yup the yeast needs nutrient.

I would stir in 1tsp of a proprietary nutrient, soon as.
Thank you for your reply I will do that and hope it recovers. Do you think it's the way I've approached pressure fermenting, building pressure from the start? Should I allow it to vent normally with no pressure until the yeast gets going then apply pressure towards the end of fermentation only?
 
I can't comment on pressure fermentation. I never have. Don't make lager, so I have written it off.

But that did not affect my answer. The yeast is screaming for nutient.

Taste it, if it is a lingering off flavour we can fix that too. Shout up!
 
Consider the fact that all healthy fermentations throw some degree of sulphur. Then consider the fact that you are pressing the yeast cells to perform under conditions that they don't love. Finally consider the fact that if you can smell it, the sulphur is thus no longer in the beer, but has left the beer.

I wouldn't worry about it, and wouldn't touch a thing. Just be patient. Any sulphur that shows up in the finished beer will disappear within a couple of weeks after packaging anyway, it always does.

Personally, I also wouldn't ferment under pressure, as I don't see a point. But you do you. And experimentation is never a bad thing.
 
Consider the fact that all healthy fermentations throw some degree of sulphur. Then consider the fact that you are pressing the yeast cells to perform under conditions that they don't love. Finally consider the fact that if you can smell it, the sulphur is thus no longer in the beer, but has left the beer.

I wouldn't worry about it, and wouldn't touch a thing. Just be patient. Any sulphur that shows up in the finished beer will disappear within a couple of weeks after packaging anyway, it always does.

Personally, I also wouldn't ferment under pressure, as I don't see a point. But you do you. And experimentation is never a bad thing.
Yeah I'm not going to pressure ferment in the future, I think it was a case of getting all the kit without any knowledge. There's no really benefit for the styles I want to brew apart from low O2 I guess but with good practices I should limit most of that risk anyway. I'll probably just use small amounts of pressure to move and package beer as my set up is all on the same level so would remove the need to pick up and elevate the fermenter when packaging.
 
That is not normal.
No that was my fear, I'm hoping being under pressure the sulphur smell and no where to go and it's imparted that smell in to the beer. Do you think it's salvageable? Apart from the smell and taste it looks fine, no worrying moulds, oil slicks discoloration etc.
 
No that was my fear, I'm hoping being under pressure the sulphur smell and no where to go and it's imparted that smell in to the beer. Do you think it's salvageable? Apart from the smell and taste it looks fine, no worrying moulds, oil slicks discoloration etc.
Defo recoverable.
 
Yeah I'm not going to pressure ferment in the future, I think it was a case of getting all the kit without any knowledge. There's no really benefit for the styles I want to brew apart from low O2 I guess but with good practices I should limit most of that risk anyway. I'll probably just use small amounts of pressure to move and package beer as my set up is all on the same level so would remove the need to pick up and elevate the fermenter when packaging.
Listening to the modern day experts can be a downfall.
Learn to brew before going down the I have £000s to spend on the latest gimmick, it may be good but not always. Too many brewers have been brewing not long enough to understand the basics but oh my god everybody needs to buy a pressure fermentor as the manufacturers say it is the way to go while pocketing their profits.
 
I've been pressure fermenting using the keg King chubby and had a about 5 successful brews, the last too have been disposed off unfortunately due to very and I mean very strong sulphur smells and the beer tasting similar to how it smelt.
If the outcome has changed, the process of fermenting at 5 PSI remained constant in these first 7 brews, then that would suggest pressure isn't the cause of the problem.

One complaint with pressure fermenting lagers is that desired sulphur notes are muted. You should be getting less sulphur, not more. Pressure fermenting is unnecessary in some styles as it reduces desired flavours and aromas, making beers characterless. I wouldn't assume this is the cause of your issue.

What yeast have you used in the last 7 brews? How are you handling it? How much are you pitching.

I'd very much be looking at cleaning and sanitation. It's a recuring theme with new brewers I'm afraid, first few brews are OK, then an off flavour starts becoming prevalent. Usually a biofilm issue.
 
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If the outcome has changed, the process of fermenting at 5 PSI remained constant in these first 7 brews, then that would suggest pressure isn't the cause of the problem.

One complaint with pressure fermenting lagers is that desired sulphur notes are muted. You should be getting less sulphur, not more. Pressure fermenting is unnecessary in some styles as it reduces desired flavours and aromas, making beers characterless. I wouldn't assume this is the cause of your issue.

What yeast have you used in the last 7 brews? How are you handling it? How much are you pitching.

I'd very much be looking at cleaning and sanitation. It's a recuring theme with new brewers I'm afraid, first few brews are OK, then an off flavour starts becoming prevalent. Usually a biofilm issue.
The yeast I was using is the Mangrove Jack's M44 US West Coast that came in the kit, 10g I believe. I thought my sanitation and cleaning was pretty good, I guess there is a difference between clean and beer clean so I will have a look at my process just to rule that out. I have brew going at the moment that is going great using the same equipment apart from the pressure vessel I've just left it in the plastic fermenter with an air lock and not decanted in to the pressure fermenter. So the issue is with that I guess just what is a mystery. I've depressurised it and just left it in the garage ready to ditch and the smell has faded slightly and it doesn't taste too bad so don't think it's infected but could be wrong, if I didnt know what is smelt like a few days ago I wouldn't think anything was wrong.
 
Don't panic.
I've had this issue with MJ M42. Nutrient helps a lot, but I won't use M42 again.
I've had beer which was so " tainted it was undrinkable, but it does clean itself up eventually, even if it takes many months.
I now, add nutrient to all my beers.
 
Listening to the modern day experts can be a downfall.
Learn to brew before going down the I have £000s to spend on the latest gimmick, it may be good but not always. Too many brewers have been brewing not long enough to understand the basics but oh my god everybody needs to buy a pressure fermentor as the manufacturers say it is the way to go while pocketing their profits.
Guilty as charged! I was swept away with my new hobby for sure, thankfully it was £80 so although it hurts and a waste of money I can learn from it and get the basics right. I've gone back to the standard plastic fermenter and airlock for my lastest brew and it's going great so far and alot less faffing without all the various lines and disconnects!
 
I've heard that only lager yeasts can handle pressure. M44 is an ale yeast (top fermenter), so it really isn't built for pressurization.
 

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