Do campden tablets de-chlorinate water

I have read conflicting reports about the use of campden tablets (aka potassium metabisulfite) to de-chlorinate water. Some sites say filter your water with a charcoal filter to remove the chlorine then add Campden tablets to remove Chloramines. I have also read that campden tablets remove both chlorine and chloramines. Does anyone have any type of report on this subject or some knowledge in regards to the effectiveness of removing chlorine with campden tablets?

King of Cascade said:

I have read conflicting reports about the use of campden tablets (aka potassium metabisulfite) to de-chlorinate water. Some sites say filter your water with a charcoal filter to remove the chlorine then add Campden tablets to remove Chloramines. I have also read that campden tablets remove both chlorine and chloramines. Does anyone have any type of report on this subject or some knowledge in regards to the effectiveness of removing chlorine with campden tablets?

Click to expand...

carbon filtering removes both chlorine and chloramines. Campden tablets remove both as well. Boiling alone, will remove chlorine (since it's fairly unstable) but not chloramines.

King of Cascade said:

Some sites say filter your water with a charcoal filter to remove the chlorine then add Campden tablets to remove Chloramines. ?

Click to expand...

Activated charcoal (aka: activated carbon) filters are not all created equally and not designed to do the same jobs. Some are whole house filters, shower filters and drinking water filters. The drinking water filters usually do a better job. The amount of both chlorine and chloramine removed or reduced varies widely. If you are considering a filter carefully read the manufactors specs to see the various levels of reduction you are getting from each filter.
Carbon filters remove chemicals such as chlorine and chloramine by absorbing them into the carbon medium. Adding another chemical such as campden tablets changes the chemical make up of chlorine and chloramine, such as changing chloramine into sulfites.

Denny claims that boiling drives the sulfites off. I don't know, he's probably correct. But I personally want to remove chemicals from my water not add more!

Does a carbon snake do well in cleaning up water?

http://***********/mrwizard/1211.html

Nice link brewhead that answers my questions. Thanks

it's not how much you know - it's if you know where to find it

so if you use campden to dechorinate wouldnt that kill the yeast??

MikeFlynn74 said:

so if you use campden to dechorinate wouldnt that kill the yeast??

Click to expand...

no no no no only because my post needs 10 characters or more

is there a difference between sodium and potassium metabisulfite?

instereo13 said:

is there a difference between sodium and potassium metabisulfite?

Click to expand...

Sure, one has Sodium. The other, Potassium.

It's the Sulfites that do the work here. The sulfites bind with the chlorine and create Sulfur which is readily released. The process also liberates a small (varied by municipality) amount of Ammonia, usually no more than 0.5ppm.

MikeFlynn74 said:

so if you use campden to dechorinate wouldnt that kill the yeast??

Click to expand...

First you use a very low level of sulfite to dechlorinate the water. I tablet will dechlorinate all your brewing water, winemakers use 1 tablet per gallon 24 hours before pitching.
Second most brewing yeasts are somewhat sulfite tolerant
Third I believe leaving it sit open over night plus the boiling process removes most of the SO2 from the beer.

So no it will not harm your yeasts.

Craig

Thanks Barron!

I use Campden and it works great. My water is cholorinated and boiling is slow and wastes propane.

So, if I understand this right....

IF you use Campden and let it sit for a while.... then you mash.... then you brew... and you boil.... then all the sulfites (which used to be chloramines) are driven off through evaporation.

Then, if you DIDN'T boil (pretend you were doing one of the many "alternate boil" methods, no-boil, 15-minute-boil, etc etc) would you still have problems with the sulfites being present, since you did not give them the opportunity to exit the wort through boiling?

"you still have problems with the sulfites being present"

No the sulfites are converted to sulfates which is added to brewing water in the form of (calcium sulfate)

chriso said:

So, if I understand this right....

IF you use Campden and let it sit for a while.... then you mash.... then you brew... and you boil....

Click to expand...

You don't even need to let it sit for a while. According to Palmer, the reaction between the campden tablet and chlorine/chloramine is nearly instantaneous. I just crush up the tablet between two spoons and dissolve it in my brew water as it is heating. Easy and works great.

Cool, thanks for clarifying. I have to try this on my next batch. Our water is high in chloramines and I have not done anything to treat it yet, just used tap water as-is so far.

Cool thread. I'm an extract brewer, so I only boil half my water. I understand that adding campden tablets to the boiling water neutralizes both chlorine and chloramine, but how about the tap water with chloramine that fills the rest of the fermenter?

Regarding the use of Campden to knock out chloramines, are you dosing your water prior to the mash/sparge or the pre-boil wort volume?

I have been using Campden to treat my strike water and, when I remember, the sparge water, while heating them to temp. I don't know if that's the right usage......

flyangler18 said:

Regarding the use of Campden to knock out chloramines, are you dosing your water prior to the mash/sparge or the pre-boil wort volume?

Click to expand...

Yea...use it to treat strike and sparge water. No need to treat wort if the mash water has been treated

Cool. We just got word that the water company taking over on the local contract will be using chloramines so I'm planning ahead. Granted, it's three months down the line.

You want to treat all the water used in your brewing to remove chlorine. I fill an 8gal bucket before starting and use that water for strike and sparge. If I need top up I use RO water but that is not often.
The chlorine will react with compounds in the mash as well as the boil to create undesirable flavors. Get rid of them before using the water.

A charcoal filter is the best way to prepare water for brewing as it also removes some other flavor causing compounds from the water. However if your water tastes good but has chlorine then campden tablets are an easy solution.

Craig

CBBaron said:

You want to treat all the water used in your brewing to remove chlorine. I fill an 8gal bucket before starting and use that water for strike and sparge. If I need top up I use RO water but that is not often.
The chlorine will react with compounds in the mash as well as the boil to create undesirable flavors. Get rid of them before using the water.

A charcoal filter is the best way to prepare water for brewing as it also removes some other flavor causing compounds from the water. However if your water tastes good but has chlorine then campden tablets are an easy solution.

Craig

Click to expand...

I agree with using a charcole filter first to remove the chlorine then adding the campden to take care of the chloramines

Mr. Wizard on the BYO article said one 1/2 ounce Campden tablet is enough to treat 20 gallons of water. Does anyone know if Campden tablets are pure sodium metabisulfite, or does it have something else in it too?

King of Cascade said:

I agree with using a charcole filter first to remove the chlorine then adding the campden to take care of the chloramines

Click to expand...

My understanding is that charcoal filter will remove both from the water. You do have to run it slow though and not just flush the water through the filter. The charcoal actually absorbs the chemicals instead of actually filtering them so the longer the water is in contact with the charcoal the more effective it is. It is possible that chloramines take a longer contact time than chlorine.

Craig

billtzk said:

Mr. Wizard on the BYO article said one 1/2 ounce Campden tablet is enough to treat 20 gallons of water. Does anyone know if Campden tablets are pure sodium metabisulfite, or does it have something else in it too?

Click to expand...

They can be either pure or a combination of sodium and potassium metabisulfite. There shouldn't be any filler.

1/2 an ounce (15 grams) is more than enough, but it depends on how much chlorine your town adds. It doesn't take much to neutralize the chlorine or chloramine, I prepare about 60L of water for my 10gallon batches (60L is about 15gallons) and I add maybe .6grams of metabisulfite to neutralize 4ppm of chloramine. Haven't had an off flavour since doing this.

On reading the article, I think Mr Wizards masses are off. He quotes 1/2 ounce per tablet, but that's 15 grams, the pill would choke a horse.

Most campden tablets I see are .5 grams, or 1/60 of an ounce. At this size, one tablet will treat 20gallons of 2ppm chlorine.

Charcoal filters are effective in removing chlorine but less effective removing chloramines. I prefer both and if I’m making a special beer I even preboil my water the day before then let it rest 24 hours.

I use 1/8 tsp potassium metabisulfite per 15 gallons

How did you come up with 1/8 tsp of potassium metabisulfite for 15 gallons of water, King of Cascade? Also since the molecular weight of potassium and sodium metabisulfite are different (222.32 for K2S2O5, and 190.13 for NA2S2O5), do you happen to know how to calculate how much would be required for sodium metabisulfite?

By the way, my local water supply averages 2.4 ppm residual chlorine, with min and max of 1 and 4 ppm. The water report doesn't mention chloramine.

Just a warning about BYO's Wizard.

I don't have it in front of me, but in one article he recommends half an ounce of metabisulfite per 10-20 gallons of water to remove chlorine; it should be half a campden tablet (about 250 mg).

FlyGuy said:

You don't even need to let it sit for a while. According to Palmer, the reaction between the campden tablet and chlorine/chloramine is nearly instantaneous. I just crush up the tablet between two spoons and dissolve it in my brew water as it is heating. Easy and works great.

Click to expand...

It was my understanding that it was nearly instantaneous too but the latest issue of BYO mentions to use campden tables to treat the water the day before to give the gas time to escape (and to not taste the water immediately after adding).

I did try tasting my 20 gallons of strike water ~15 minutes after adding a campden tablet after the last time I brewed and it has a noticeable sulphur taste.

Kal

After the boil and 3-4 week fermentation there will be none left. I have 2 beers on tap right now that I used campden in. Neither exhibit any chlorophenols or sulfur taste.

Edcculus said:

After the boil and 3-4 week fermentation there will be none left. I have 2 beers on tap right now that I used campden in. Neither exhibit any chlorophenols or sulfur taste.

Click to expand...

That's my experience too and why I do it the way I do... just curious why BYO would say you need to do it the day before. Odd.

Kal

It was just someone being overly cautious, and not really understanding the chemical reaction.

Here is a much better article from BYO on the topic:

http://***********/stories/recipes/...-clear-the-beer-of-this-compound-is-this-true

FlyGuy said:

It was just someone being overly cautious, and not really understanding the chemical reaction.

Click to expand...

Makes sense ... and thanks for the link!

Kal

Anyone have any idea how adding a campden tablet affects the minerals/salts in water?

I measured the pH of my city water at 9.2, then added 1 crushed campden tablet to 20 gallons and 5 minutes later the pH was down to 8. So there's definitely something going on there!

Kal

kal said:

Anyone have any idea how adding a campden tablet affects the minerals/salts in water?

I measured the pH of my city water at 9.2, then added 1 crushed campden tablet to 20 gallons and 5 minutes later the pH was down to 8. So there's definitely something going on there!

Kal

Click to expand...

Can anyone else speak to this? Do I need to adjust my water spreadsheet if there is campden in the mix?

are you guys still adding 1 tablet per gallon even if its to dechlorinate strike/sparge water?

i need to use these tommorow and i will need ~8-10 Gal of water for the brew. the bottle of campden tabs doesnt give any directions as to how many to use..

i was planning on filling two 5 Gallon buckets of my regular chlorinated tap water and adding the tabs to those. then fill my HLT with that water for the strike water shortly after.

does this all sound kosher to you folks?