Treating tap water with Campden tablets

[Thumper]

Hi all,

I have just ordered the Brewferm Abdij kit from homebrew online, with 500g of dark candi sugar. Should be with me by Friday, I'm hoping it will be ready for Christmas.

My previous brews have all been done with bottled water, but for this one I intend to use tap water, treated with Campden to drive off the chloramines. Ive got myself some Campden tablets from Wilko. So my question is: what ratio of Campden to water do I need?

Thanks in advance.

 

[Pavros]

I usually use half a crushed tablet in 20 litres of water, but, if the water smells more strongly of chlorine, I will use the whole tablet crushed. Then leave the water for about half an hour or so.

 

[Thumper]

Thanks Pavros. The Brewferm kit is 9l, I believe, so I should need around quarter of a tab.

From your answer, I assume using more than is needed isn't dangerous or undesirable in any way?

 

[terrym]

If you can't smell or taste chlorine in your tap water there is really not much point dosing with campden tablets imo. My tap water doesn't and I could not detect any difference with or without a Camden tablet so don't bother now.
That said if you avoid drinking your tap water for other reasons, smell and/or taste, you should not be using it for brewing.

 

[Thumper]

I drink my tap water perfectly happily, but I don't want TCP beer and it costs nothing to chuck a tablet in. Less than bottled water, in fact, which part of the reason I want to try it. This is sort of an experiment- if it goes **** up, I'll have to stick to bottled.

Where abouts do you live, terrym?

 

[terrym]

I drink my tap water perfectly happily, but I don't want TCP beer and it costs nothing to chuck a tablet in. Less than bottled water, in fact, which part of the reason I want to try it. This is sort of an experiment- if it goes **** up, I'll have to stick to bottled.

Where abouts do you live, terrym?

My water comes from SE Water, but that can mean anything when it comes to water sources and treatment, just like any tap water anywhere in the UK.
If your tap water doesn't taste of TCP before it goes into your beer it is unlikely to develop it afterwards in my opinion. But its good to experiment so go for it.:thumb:

 

[henteaser]

If your tap water doesn't taste of TCP before it goes into your beer it is unlikely to develop it afterwards in my opinion.:thumb:

This is slightly mis-leading.

Chlorine

Present in varying quantities in UK tap water. You can smell it, but it's very volatile and will dissipate readily (probably in less time than it takes to heat your sparge water).

Chloramine

You can not taste or smell it. It is much more stubborn, and can not be easily removed in the same way chlorine can (simply by letting it stand a while).

Chlorophenols

This is the actual off-flavour we're concerned with in finished beer, the medicinal "TCP" like taste which is a result of an interaction with phenols produced by yeast during fermentation, and any remaining chlorine/chloramine.

So whether or not you can smell chlorine in your tap water, is not a good indicator of the presence of chloramine.

If in doubt, 0.5 campden tablet per 5 gallons is plenty to shift it. Or use another source of water (bottled, RO etc.)

 

[Thumper]

Thanks henteaser, that was my understanding. Levels of all three are variable, and terrym might live in an area where they are low enough to have no significant effect, but I'm not willing to take the risk of 9 litres of antiseptic ������

It's beginning to look like half a tab per 5 gallon brew is the general consensus.

Off on a slight tangent, all this had got me thinking about the chemistry involved; an exercise which so far has revealed only that I've forgotten what little I learned at A level. I can't even balance an equation any more.

Anyway, Campden tablets are either sodium metabisulfite, Na2S205, or potassium metabisulfite, K2S2O5.

After dissolving in water and reacting with chloride ions, this would produce (I think) sulfates and either table salt or potassium chloride, depending in the tablet used. Is that right?

I've read that adding sulfates to the brewing water is good for accentuating the hop character of beers, a process called 'Burtonisation' after Burton on Trent. Does adding the Campden tablet Burtonise the water, or is it not enough of a concentration of sulfates to make a difference?

 

[terrym]

This is slightly mis-leading.

Chlorine

Present in varying quantities in UK tap water. You can smell it, but it's very volatile and will dissipate readily (probably in less time than it takes to heat your sparge water).

Chloramine

You can not taste or smell it. It is much more stubborn, and can not be easily removed in the same way chlorine can (simply by letting it stand a while).

Chlorophenols

This is the actual off-flavour we're concerned with in finished beer, the medicinal "TCP" like taste which is a result of an interaction with phenols produced by yeast during fermentation, and any remaining chlorine/chloramine.

So whether or not you can smell chlorine in your tap water, is not a good indicator of the presence of chloramine.

If in doubt, 0.5 campden tablet per 5 gallons is plenty to shift it. Or use another source of water (bottled, RO etc.)

Useful stuff. :thumb:

 

[Pavros]

Thanks Pavros. The Brewferm kit is 9l, I believe, so I should need around quarter of a tab.

From your answer, I assume using more than is needed isn't dangerous or undesirable in any way?

I haven't noticed any ill-effects from using a whole tablet in 20 litres. If in doubt, just let it stand longer before using.

When I said about smelling a stronger chlorine smell in my water, it sometimes happens about once a year. Usually when the water company is 'flushing' the system and puts a higher dose of chemicals through. I use this as an indication that there will be a higher level of chloramines in the water than normal.

 

[pvt_ak]

I usually use half a crushed tablet in 20 litres of water, but, if the water smells more strongly of chlorine, I will use the whole tablet crushed. Then leave the water for about half an hour or so.

+1.
My 2nd brew was TCP !!
Started using half a campden for 20l brews and sorted since.


Sent from my iPhone using Tapatalk

 

[strange-steve]

Anyway, Campden tablets are either sodium metabisulfite, Na2S205, or potassium metabisulfite, K2S2O5.

After dissolving in water and reacting with chloride ions, this would produce (I think) sulfates and either table salt or potassium chloride, depending in the tablet used. Is that right?

Not quite, it reacts with chlorine (actually hypochlorite or hypochlorous acid I think) or monochloramine (NH2Cl) rather than chloride (Cl-). The resultant compounds are sodium or potassium (depending on which metabisulphite you use) plus sulphuric acid and hydrochloric acid or ammonium chloride (which is quite brilliantly a yeast nutrient).

I've read that adding sulfates to the brewing water is good for accentuating the hop character of beers, a process called 'Burtonisation' after Burton on Trent. Does adding the Campden tablet Burtonise the water, or is it not enough of a concentration of sulfates to make a difference?

Nah, the levels of sulphates and/or chlorides are way too small to make any noticeable difference. If you want to increase sulphate then adding gypsum (calcium sulphate) is the way to go.

 

[Thumper]

Cheers Steve! I love that it creates a yeast nutrient 😂