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What is Potassium Metbisulphite used for?

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Potassium Metabisulfite is fine for sanitizing, but it's not a cleaner. Your equipment should be cleaned first, then sanitized. I think with k-meta you should rinse with boiled water, too, for beer. For wine, I use it all the time but I've never used it with beer. It smells like sulfur and minute amounts are used in it to keep nasties out of wine.
 
I use T.S.P. TriSodium Phosphate. Let my bottles soak for 24 hours and rinse them in hot water just before I bottle. Cleans the label glue off, and frees up the gunk on the inside of the bottle. Its cheap, and cleans up easy.
 
In wine making, k-meta is used for anti-oxidant protection and as an anti-microbial. You can also use k-meta to remove chlorine/chloramines from your brewing water. One tablet will do the job for 20 gallons of water.
 
Unclesamskid said:
Potassium metabisulphite is also used in cider making to stop fermentation.

Isn't potassium sorbate used for this and k-meta added to prevent a malic acid ferment?
 
johnsma22 said:
Isn't potassium sorbate used for this and k-meta added to prevent a malic acid ferment?

Yes, exactly. You can't stop fermentation with k-meta, but potassium sorbate works better in the presence of sulfites so you should sulfite with the k-meta to 50 ppm and then add your sorbate. If you don't use the k-meta when you add sorbate, you can get a geranium smell from a concurrent malic acid fermentation.

But, I've never used k-meta for beer. I don't know if ale yeasts are "immune" to k-meta the way wine yeasts are.
 
Yooper Chick said:
Yes, exactly. You can't stop fermentation with k-meta, but potassium sorbate works better in the presence of sulfites so you should sulfite with the k-meta to 50 ppm and then add your sorbate.

Yooper,

The folks at Gotmead.com seem to think that Potassium Metabisulphite can be used for stopping fermentation:

http://www.gotmead.com/index.php?option=com_content&task=view&id=445&Itemid=369
http://www.gotmead.com/index.php?option=com_smf&Itemid=412&topic=4363.msg36384#msg36384
http://www.gotmead.com/index.php?option=com_smf&Itemid=412&topic=2477.msg19645#msg19645
http://www.gotmead.com/index.php?option=com_smf&Itemid=412&topic=44.msg1127#msg1127

I have never used k-meta, so I don't know from experience. I prefer to wait, rack and repeat until it is done. I have thought about using k-meta in mead making, but I have so much brewing going on, it is just easier to make mead and forget about it.

Phooka - you might want to stop fermentation when you reach a point where you have just the right amount of residual sweetness. The mead might be too dry otherwise. Additionally, if you have a mead that is too dry and you want to backsweeten it (adding honey back to increase sweetness), you would want to stop fermentation to prevent it from drying out again, or creating bottle bombs (assuming you bottled it soon after backsweetening).
 
I can't recall where I found the recommendation now, but it was to use about 5 ppm KMS in the mash water as an anti-oxidant. Too low a concentration to have an effect on fermentation.
 
Unclesamskid said:

I'm not wanting to take this thread off topic, and I didn't have time to closely scrutinize all those posts, but here is an excerpt of one of those:

"You can pitch a more agressive yeast like K1V-1116, and stop fermentation with metabisulphite, and potassium sorbate when it reaches the desired SG."

Which is what I basically said- you use k-meta IN CONJUNCTION with sorbate to ensure no re-fermentation.

I use k-meta all the time in wine, and in 50ppm or less you most certainly will not halt fermentation. I use it to kill nasties in my fruit, and to prohibit wild yeasts from taking over. You need the sorbate to actually keep the yeasts from reproducing.

Anyway, k-meta works fine as a sanitizer for wine. I've yet to use it for beer equipment, though. I'm not 100% sure how ale yeasts would behave with sulfite, and I think it might leave a perceptible taste in beer particularly those that don't age much. I age wines a long time, and the sulfite definitely fades.
 

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