Too much sodium metabisulphite

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MattGuk

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Hi all, when brewing the other day, I treated my water for chloramine with the addition of SMB.
However I have a powdered form and usually just sprinkle a small amount.
I slipped while adding the other day and probably endud up adding close to a teaspoon.
During fermentation the smell was so bad, like egg.
Now I know this CAN be normal, but never had it before with this yeast, S-04.
Checked a sample yesterday, and I know it's only a few days but ferment has basically finished, gravity 1.012 from 1.046, yeast has pretty much dropped but this smell is still noticeable and tastes weird, almost slightly salty.
Do you think SMB at that rate would cause this? Or something else? If it is the SMB, is there anything I can do?

Thanks all
 
I had a few brews with a sulphury taste, because I had misread the water treatment guidelines and put one Campden tablet in the water (half in the mash and half in the sparge), instead of a quarter in each. I have now stopped using it altogether and haven't had an issue since.

I can't say for definite that the metabisulphate is the cause of your problem, but I think it's highly likely.
 
Yeah, think it must be, so P***ed off with myself as this was a user upper brew, looks like I'm going to have to order more stuff then lol
 
Worst thing that happens (in my desperately limited experience) is Chlorophenols - free chlorine combining with the phelons produced mainly in the initial stages of fermentation. The human sense of smell is immensely sensitive to these compounds, Why, I know not. Perhaps some very ancient association to danger, perhaps long before modern humans emerged to make beer.
 
You don't tell us what your batch size is, but a teaspoonful of SMB in, say, 25 litres, while massively too much for the amount of chlorine and chloramine in the water, is unlikely to be the only cause of the pong in your beer. There won't be much sulphite left hanging around after you've boiled it for 60-90 minutes. My experience of ghastly smells from the yeast have been entirely cured by adding a teaspoonful of yeast nutrient to the fermenter at the same time as pitching. It my be that the SMB has reduced the nutrient level. It's not too late to add some nutrient now and eventually the horrible eggy smell will get cleaned up by the yeast. It can take a long time, though.
 
I bet it's fine flavor wise. I agree with the post above, something about the yeast or other ingredients.

I've heard of people dropping a piece of copper in their wine to reduce sulfur smells. Google is your friend.
 
The SMB can be slightly toxic to yeast if too high a concentration. But this seems unlikely as stated above after a mash and boil. Some LODO fermenters advocate using it in the mash to stop oxidation of the wort. Agreed more likely yeast stress due to temperature or nutrition. Will need a bit longer in ferment and cold conditioning hopefully to get rid of it.
I have added SMB to my kegs to act as a reducing agent to scrub oxygen remnants and in wine making regularly added at the bottling or racking stage without sulphury off notes.
Wait and see, but I expect you'll never find the answer.
Any other odd water treatments done such as an original burton water profile?
 
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