How critical is the amount of camden tablet?

[guypettigrew]

Having started treating my water relatively recently, with excellent results, I'm wondering about the camden tablet addition.

My current regime is to add half a camden tablet to the mash liquor and the same to the sparge liquor.

Is there any need to cut the tablet in half, which is a bit fiddly, or can I just add a whole tablet each time?

Thanks.

Guy

[Horden Hillbilly]

Is there any need to cut the tablet in half, which is a bit fiddly, or can I just add a whole tablet each time?

You could always get campden powder

[jmc]

I think you only need 1/2 tablet per 50L water.

I use a solution of sodium metabisulphate. No worries then about crushing tablets or whether it dissolved on not.

[guypettigrew]

Thanks for the replies.

So. if I use the Camden powder, what rate (grams/litre) should it be used at, please?

Guy

[Aleman]

1 campden tablet will treat 3ppm chlorine in 17UK gallons of water.

In my case the residual chlorine is 0.35ppm so 1 campden tablet will treat ~170 Gallons. I don't cut in half or crush . . . I dissolve in a known volume of water (~10ml) and then use an appropriate amount.

In all grain brewing overdosing is not critical, as the sulphite will behave as a reductone in the mash, there is a theory that using too much in a kit beer will lead to excessive hydrogen sulphide production. . . while this is a possibility it is more probable that excess sulphite will also act as a reductone in the beer. . . . it will all depend on the required activation energies of the various (many) metabolic pathways.

Some breweries have no problems with the levels of residual chlorine in their brewing liquor, Here when drawing liquor at weekends the chlorine level is easily detectable via smell.

I do agree with Graham though that a vast majority of TCP/Phenols in the final beer is probably due to an infection or even insufficient rinsing of a chlorine based cleanser/disinfectant. . . .When I used to use such I would always do a final rinse with a metabisulphite solution, which neutralises the chlorine (Not that I knew it at the time )

[Aleman]

So. if I use the Camden powder, what rate (grams/litre) should it be used at, please?

I think (but would have to check) that it is 5ml of a 10% solution gives 50ppm sulphite which will treat 3ppm chlorine in 17UK gallons

[greenxpaddy]

I use 3/4 tablet per 50L, which is even fiddlier! or 2 tabs for 150L

[potatoes]

In relation to adding the camden tablet, Does it matter when it is added? Is this best done before the mash, or after the mash or after the boil?

[dcq1974]

Sounds correct Aleman

IIRC 5 ml of a 10% Sodium Metabisulphide solution is equivalent to a single Camden tablet

[jmc]

Sounds correct Aleman

IIRC 5 ml of a 10% Sodium Metabisulphide solution is equivalent to a single Camden tablet

Thanks DCQ

I've based my camden tablet calcs on a previous post of yours
I've been using it for ages and no probs with chlorine off-taste.

I've even accidentaly over dosed on one brew 10x, by using the wrong bottle (10% solution rather than normal 1%)
But luckily brew was fine

I think overdoing camden tablet with AG doesn't cause a lot of harm as long as its added before mash & boil.
as I would have thought that any excess SO2 would boil off.