Hi all,
I understand the Sodium/Potassium Metabisulfite will ‘neutralize’ chlorine or chloramine from mash water, but does anyone know if it will do the same for chlorine in the fermenter? If so are there negative effects on flavor, yeast health, …? Due to my stupidity I ended up with residual chlorine in my Speidel fermenter (cleaned it with bleach) and it leached out into the wort during fermentation. Result was massive cholorphonel and 5 gallons of Belgian Dubbel down the drain $$. I think I’ve effectively removed the chlorine with soaks of hot (135 F) water and campden tablets, but I’m wondering if a dose of same in the fermenter would be wise as a precautionary measure.
Thanks in advance.
I believe that chlorine will naturally escape off overnight. If you use a campden tablet or filter the water first, you should not have a problem. At certain levels, the S/P metabisulfate will create a ‘fart-like’ flavor in your beer. I was using it for O2 control and the low-O2 guys were playing with the amounts … 100ppm, 50ppm, 25ppm, 12.5ppm … I could still taste it so I stopped using it. But getting the chlorine out of your water prior to brewday should be easy. Just get your volume of water ready the day before you brew and it should gas off. If that’s not handy, a carbon block water filter should work. I filter all of my water through a water filter either the day before or the day of brewing because my source water smells and tastes like a public pool.
Thanks, the chlorine actually got into the plastic when I foolishly used a bleach solution to clean the fermenter. At the time I thought I might have diastaticus lingering in it, and if that was the case it meant my PBW/Starsan cleaning regiment was not removing it. The brewing water is distilled, no chlor(am)ine.
“fart-like flavor” … Please expound on this one!!
Seriously. Anyone who was dabbling in low(er)-O2 knows what I’m talking about. The S/P metabisulfate is a good O2 scavenger and was part of a triple insurance policy against O2 along with BTB and ascorbic acid. It was supposed to be there for when O2 does creep into your process but at first the level to use was unknown. I lifted a few glasses of beer to my nose where it smelled like I was drinking straight-up farts. Heavy sulfur. Someone mentioned that it would age out but I didn’t experience that. I went down to 12.5ppm and I could still pick it up so I bailed on it. I’m not spending 4 hours of my time to drink fart beer, no sir. Imagine serving it to friends! :o
That is a reasonable concern, but you should have used iodophor instead of chlorine.
+1. I was in the same boat and bailed on everything but BtB.
Lately, I have been using ‘OxBlox’ from MoreBeer at .3 grams per gallon strike liquor with really good results. It’s the trifecta blend. I am not sure if I am supposed to but I have been using it in the mash. I use BtB along with it in the mash and boil.
One day, you’ll wake up and there won’t be anymore time to do the things you’ve always wanted to do. Don’t wait. Do it now.
Thanks all, but the concern is not chlorine in the mash water. It’s in the fermenter. I know using a bleach solution to clean the fermenter was a mistake. I am now trying to establish if there is a risk to adding S/P Metabisulfite to the fermenter in an attempt to scavenge any chlorine that leaches out of the plastic during fermentation.
The reaction between malt components in wort and chlorine compounds is fairly instantaneous. So you won’t be able to avoid chlorophenols in the beer by adding metabisulfite after the fact. It’s got to be added to the water before that water ever touches the grain.
Now regarding the use of metabisulfite to leave a prophylactic protection against chlorine coming out of plastic, that would be a use that could have merit. Don’t over do it though.
Thank you Martin, that answers my question. One follow up if I may.
If the mash contains S/P Metabisulfite but the mash is devoid of chlor(am)ine, would the S/P Meta still be around post boil?
So, this was in there for the actual fermentation? I wonder if the fermentation contributed to the sulfur or something.
I’ve used the potassium metabisulfate + ascorbic acid when kegging and didn’t notice any sulfur, but fermentation was complete by that point. I’d have to check my notes to figure out the ppm, but I’m sure it was over 12.5.
Yes. The trifecta (BTB, SMB, AA) was added to the mash. The trick was to find the right amount because if you’re too low and you’re concerned about O2 pickup, you’ll be short. If you go overboard, you’re left with farty beer … the SMB does not age out or get taken out by the boil or any of that. The ppm on the SMB was critical and even then you could be in trouble because if the SMB is not expended (because the process was solid enough that there wasn’t much O2 in the process to begin with), it would remain and cause this flavor. The first time it happened the beer was undrinkable. But even when I thought I got it right, I could still pick it up. Maybe I’m sensitive to the flavor/aroma. I stopped using it shortly thereafter.
I guess now I’m going to be looking for it. Haven’t noticed it before, but I’ve only added it to IPAs, so maybe it’s just hiding behind the hops. I’m sure it would have very little to hide behind in one of your lagers. 
Probably. Even when I was following the low-O2 stuff, the guys there were trying to find the right amount to use and they admitted that any ‘unused’ SMB in the beer would produce this flavor so the best bet was to use “just a little less than what you might need” so that there wasn’t leftover SMB in the beer.
I went through the low-ox approach over several years and was making beers with about a gram of KMeta, a gram of Brewtan B and a gram of Ascorbic Acid in a 5 gallon batch in the mash. I would pre-boil the water and chill to mash temp before adding the water treatment and the grains to dough in with a mash cap (pizza pan that fit the mash tun perfectly with a silicone gasket). After many, many batches, I pulled out the KMeta and Ascorbic Acid and quit using those. Then eventually, I let go of the pre-boiling and simply avoided excessive splashing. The beers seem to turn out fine (I won awards both ways), so I just live with the gentle stirring and modest boil to keep O2 at bay without undertaking more aggressive low O2 measures. I am not saying that my Helles is just as good as the German brewers or low O2 adherents, but I haven’t had one turned down when offered for as long as I can remember.
Just sayin’…KMeta isn’t an absolute necessary addition to a good pale lager.
Instead of the boiling and chilling, I used (and still do) the yeast + sugar addition to the brewing water. It’s supposed to bring the O2 level down to close to zero within about 20 minutes. I still have some of my low(er)-O2 processes in place but the SMB/AA is out of my process now.
Here is how it all turned out. I started this thread asking if it would be possible to use SMeta in the FERMENTER (plastic Spiedel) to scavenge some residual chlorine that I had left over from an attempted sanitation (stupid move on my part).
After attempting to clean to remove the chlorine with a soak of 140F water and SMeta, I ran a 2 gallon test batch consisting of 2 lbs DME, ½ lb of homemade candy syrup and some old hops. Fermented with Mangrove M41 which I knew would dry it out. I did not detect any chlorophenols in the finished 3.5% beer. It actually wasn’t bad.
I went ahead with a 5 gal batch of French Farmhouse, and following Martin’s suggestion that it might be worth a try, added SMeta to the fermenter. Fermented it with Lallemand Farmhouse and M41, the latter of which I knew could throw some sulfur. However, this batch threw sulfur like nothing I had ever smelled. Horrific. Similar to the experience cited above by Village Taphouse.
Let it ferment out and condition, total of about 3 weeks. Kegged and carbonated. Tasted off and I believe I could smell faint sulfur. I could not tell if I was tasting sulfur, or chlorophenol. I was looking for chlorophenol since I was trying to rescue the fermenter.
I was ready to dump the batch, it tasted bad. Then I re-read this thread, specifically the comments about sulfur. Thinking about how I could get rid of sulfur I recalled an episode of the brew files when Denny commented that to get rid of sulfur you throw a hunk of copper in the fermenter. Or at least that’s what I thought I recalled. I suspended a hunk of coper in the keg from the lid for about 4 hours, and it seems to have removed the bad flavor and my perceived sulfur smell. I can only conclude that it was in fact sulfur, not chlorophenol.
So that seems to have saved the batch, and I can corroborate the sulfur created in a fermentation containing SMeta. Again, my fermentation included a yeast that I knew to throw sulfur, so perhaps the SMeta amplifies the yeast’s production of sulfur. Meta-bisulfite, right?