# Effects of chlorine in mash



## Doctormcbrewdle (14/1/21)

Hey all,

My local municipality water is treated with chlorine and can actually get quite high in the summer (I can smell it when gushing into a container from tap) 

I understand this simply boils off but are there any known effects of this in the mash?

Thanks


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## MHB (14/1/21)

Remove it, it can add nothing good to the flavour of your beer.
In the snip following it says it reacts with Alcohol that's a technical term, there are millions of Alcohols not just Ethanol, Phenolic alcohols have the typical -OH (hydroxyl) functional group that makes something an alcohol. These are found in malt husks (and hops) so yes Chlorine/Chloramines in the mash will form Chlorophenols.
Carbon filtration or Metabisulfite are both very effective, with Met, I would add it to my water early and leave it there while the water was heating to strike temperatures. gives it a chance to scavenge all the Cl and for any excess to gas off.
Will post the Complete beer fault guide again, keep a copy and use it often!
Mark


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## Doctormcbrewdle (14/1/21)

Thanks Mark. And of course I recently threw my MSB out because I thought I'd never use it. Murphy's law!..


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## Doctormcbrewdle (14/1/21)

How much should I use in 30 litres guys, and is too much harmful or does it simply gas-off?


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## MHB (14/1/21)

That is in the snip above, you might have to do a bit of fingercounting to convert to metric.


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## An Ankoù (14/1/21)

Doctormcbrewdle said:


> Hey all,
> 
> My local municipality water is treated with chlorine and can actually get quite high in the summer (I can smell it when gushing into a container from tap)
> 
> ...


I don't know about it doing harm in the mash, perhaps oxidation issues, but it will certainly ruin your beer when it combines with phenolic compounds in the hops during the boil. It'll produce a variety of chlorophenols which have a very low taste threshold, will make your beer taste strongly of mouthwash and render it totally unfit for drinking.
Treat 5 -10 gallons of water with half a Campden tablet or a quarter teaspoonful of sodium metabisulphite to get rid of the chlorine and / or chloramine in the water supply. You'll need to treat both the mash and the sparge water.
Believe me, I know. It happened to me when I moved to france and I had to ditch 2 batches.


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## Dozer71 (14/1/21)

There is chlorine and chloramine which water authorities use. Chlorine can dissipate with boiling or leaving exposed for a period of time before using (like overnight) or by filtering. Chloramine is harder to get rid of. SMB or campden tablets will do it as will ascorbic acid (vitamin C). I use ascorbic acid (from chemist warehouse) at the rate of 0.3g/30L of water,


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## Doctormcbrewdle (14/1/21)

Thanks guys. I do recall using Campden tablets a few years ago and stopped without noticing any difference but it's also possible other things changed too so who really knows for sure. Can't hurt to try again I guess


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## kadmium (14/1/21)

Doctormcbrewdle said:


> How much should I use in 30 litres guys, and is too much harmful or does it simply gas-off?


Using Kmeta (Potassium Metabisulphate) you want to target about 0.005g/l or 0.5g for 10L. The reaction occurs almost instantly and so you can add it 30 seconds before mashing in. 

I however am in the habit of adding my salts, kmeta and lactic acid to cold water because temperature reduces the effectiveness of lactic acid so always add lactic acid to cold water. As such, my habit is to fill the mash water from the cold tap, add the kmeta, stir, add the salts, stir and add lactic acid. 

Be aware Kmeta can induce asthma attacks if inhaled, even if no previous history of asthma so don't go breathing it in. No need to wear a mask, but just be gentle with it. It resembles a salt or sugar like crystal substance. 

The alternative is to add Camden tablets, however I find Kmet to be far cheaper, and means I can add it to my mash and sparge water as needed. You will need an accurate scale though. 

I use a reloading scale that goes down to .001 of a gram.


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## kadmium (14/1/21)

Oh and in my opinion avoid SMB as I believe it can leave a residual taste due to bisulfites. 

Also ascorbic acid can be used, but in my opinion accurately weighed KMeta is the way to go.


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## MHB (14/1/21)

Dozer71 said:


> There is chlorine and chloramine which water authorities use. Chlorine can dissipate with boiling or leaving exposed for a period of time before using (like overnight) or by filtering. Chloramine is harder to get rid of. SMB or campden tablets will do it as will ascorbic acid (vitamin C). I use ascorbic acid (from chemist warehouse) at the rate of 0.3g/30L of water,


That will work, its not quite enough if the free Cl is right up at the limit of Australian Drinking Water Guidelines (5ppm). That's only likely to happen if you were very close to the water treatment plant, or there is some sort of emergency treatment (remember giardia) the Cl is used up as it works its way through the system.
Leaving in a bucket can be a lot slower than people think, probably several days in the sun would do it, less I'm not so sure.
If you way overdose, especially with Lager yeast (different way of handling Sulphur than Ale yeast), the extra free S can impact flavours and aroma, if you add early (I'm another brewer that does his water chemistry early - at ambient) then checks the pH at mashing temps. By the time you heat to strike temperature, it will have reacted and most of any excess will have evaporated.

Kadmium and I have slightly different views on K and Na Metabisulfite (NB not Bisulphate) Its the Met part that reacts with chlorine so both work exactly the same way, its just the residual K or Na that's different, at the doses we are talking about I couldn't tell the difference. If you happen to have three place scales you trust then weighing the powder would be cheaper. But reliable scales like that aren't cheap (about three lifetimes supply of Campden tablets).

If you aren't sure how much difference it makes, fill a bottle with tap water, another with dechlorinated tap water, carbonate (fizz tops are handy) taste them alongside each other. There is a big difference, making mineral water at home is cheap and easy for keggers, dechlorinated and it tastes way better.
Mark


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## kadmium (14/1/21)

Yeah I was more meaning if you go heavy handed with the SMB but forgot it's the MB that reacts. I barely passed year 12 

Makes sense, in which case go with what ever. Agreed good scales aren't cheap, but they are useful for salt additions I have found too. I think I paid around $65 for mine.


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## An Ankoù (14/1/21)

kadmium said:


> Oh and in my opinion avoid SMB as I believe it can leave a residual taste due to bisulfites.
> 
> Also ascorbic acid can be used, but in my opinion accurately weighed KMeta is the way to go.


Potassium metabisuphite and sodium metabisulphite have the same chemical structure apart from substituting K+ for Na+ so there should be no difference in any residual tastes.
If you chuck in a half a campden tablet in 5 gallons,, or even a full one, you've got far more than you need to neutralise the chlorine/chloramine, but the excess won't hurt as it'll just oxidise to sodium sulphate and then probably precipitate out as calcium suphate. The amounts are too small in a 5 gallon batch to make any significant difference to the water or mash chemistry.
Yes, beware of sniffing the powder in the tub, or any solution you have made and left for a while. it gives off Sulphur Dioxide (the stuff that comes out of volcanoes and kills Pompeiians with regular monotony. Getting a lungful of the stuff leads to all sorts of coughing and spluttering- none of it pleasant.


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## Doctormcbrewdle (15/1/21)

Some good reading, thanks

I actually bought the SMB for packaging (scrubbing all oxygen in the keg) used it once in a pale ale. Now, I'm not sure if I had an infection or it was the SMB but that batch was a horrendous tipper hence me throwing it away so I'm naturally very wary of using it anywhere in beer now. Think I used about quart a teaspoon in that batch.

My best guess is that it stressed residual yeast who inturn threw all kinds of off flavours


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## kadmium (15/1/21)

Doctormcbrewdle said:


> Some good reading, thanks
> 
> I actually bought the SMB for packaging (scrubbing all oxygen in the keg) used it once in a pale ale. Now, I'm not sure if I had an infection or it was the SMB but that batch was a horrendous tipper hence me throwing it away so I'm naturally very wary of using it anywhere in beer now. Think I used about quart a teaspoon in that batch.
> 
> My best guess is that it stressed residual yeast who inturn threw all kinds of off flavours


I would almost guarantee that it had no effect. I use it often in Mead making to stabilise before back sweetening.


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## Grok (15/1/21)

kadmium said:


> Using Kmeta (Potassium Metabisulphate) you want to target about 0.005g/l or 0.5g for 10L ????


Soooo, which formula is it? 2 different ones here!


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## MHB (15/1/21)

Just remember that Wine Cider and Mead yeasts are breed to be tolerant of up to 50ppm of free SO2. This is not the case with Beer yeasts.
Arguable the effect is fast but it isn't instant, I would be adding Met at least 15 minutes before mashing in, that way it has time to react and any excess can evaporate out. People with a background in wine making tend to underestimate how bad Met can be for beer yeast, wine makers tend to think in wide mouthed shovels, we have to be a lot more cautious.
This is pretty handy talks about Cl and O2 removal The Removal of Oxygen and Chlorine from Water
Remembering that any Met that reacts with O2 isn't available to remove Cl and Vice Versa.
A small excess and some time to all settle out is probably the safest option unless you have a dam good lab handy.
Mark


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## kadmium (15/1/21)

Grok said:


> Soooo, which formula is it? 2 different ones here!


Hahahaha. 0.05 for 10L


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## Doctormcbrewdle (16/1/21)

Hey guys, I'm just out enjoying the fruits of homebrew labor while having a dip and notice that my pale ale smells of glorious fruit and resin one minute, then I jump in the pool and everything changes perception. Fruit is gone and replaced with a bandaid kind of taste and aroma. How does this work?


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## S.E (16/1/21)

Doctormcbrewdle said:


> Hey guys, I'm just out enjoying the fruits of homebrew labor while having a dip and notice that my pale ale smells of glorious fruit and resin one minute, then I jump in the pool and everything changes perception. Fruit is gone and replaced with a bandaid kind of taste and aroma. How does this work?View attachment 119825


I think I may know but need a little more info. When you say “jump in the pool” did you pool bomb? And when you got out did there did there seem to be more beer in the glass than before?


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## Doctormcbrewdle (16/1/21)

No, just sitting in the pool is more than enough for this to happen. Takes a god 5-10 minutes to return to normal after getting out too for what it's worth


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## razz (16/1/21)

Doctormcbrewdle said:


> No, just sitting in the pool is more than enough for this to happen. Takes a god 5-10 minutes to return to normal after getting out too for what it's worth


Maybe your Olefactory senses picking up on the pool water odour and affecting your taste for a few minutes. Your the doctor, you should know!


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## MHB (16/1/21)

Got a face full of Cl gas once, couldn't smell or taste much for months. I'm still pretty sensitive to Chlorine, the faintest trace feels like a barbwire pull-through up the sinuses.
Would rather swim in the sea.
Mark


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## Doctormcbrewdle (17/1/21)

Yes, it probably just throws the senses out a bit as you say I guess

Thanks mate


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