Campden tablets necessary if diluting with RO?

[FirstAidBrewing]

Hey All,

got a shiny new water report and so I'm about to brew for the first time with RO-diluted water. Getting ready to fire up the monster! :rockin:

I've always used CAmpden tablets to treat Chloride but I am wondering if I no longer need to do this since I am cutting my Chloride ppm in half with my RO water additions. My EZ Water spreadsheet would indicate that I don't need to do this.

Thoughts?

 

[PlinyTheMiddleAged]

FirstAid,

I'd definitely still use the Campden tablet on the tap water. They're pretty cheap and it doesn't take much chlorine to ruin a batch of beer. Insurance is cheap!

Cheers!

 

[FirstAidBrewing]

thank you sir

 

[Yooper]

Campden doesn't reduce chloride- it removes chlorine. Chlorine is a disinfectant that is in many municipal water supplies and the interaction of chlorine and malt produces terrible phenolic flavors in beer if combined.

Chloride is a difference substance. Depending on what you are making, you may want 50-100 ppm of chloride in your water for the flavor contribution to the beer.

 

[ajdelange]

Confusion over chloride, chlorine and chloramine aside there is some level of chlorine (free or as combined in chloramine) below which you will not have a problem. Even if your water is quite high in one or the other or both if you dilute it enough with RO then the concentration(s) will be low enough to be harmless.

There are some simple tests you can do to see if you have chlorine or chloramine in your tap. You could do the same tests with diluted tap water. In a nutshell: if you can't smell chlorine you are probably OK. OTOH part of a Campden tablet is cheap insurance.

See https://www.homebrewtalk.com/f128/campden-tablets-sulfites-brewing-water-361073/ for details.

 

[mabrungard]

Well FirstAid, if you don't want BandAid, you should still use the Campden to remove the chlorine compounds in your tap water. ;-)

It takes incredibly little chlorophenol in beer to become noticeable. Its not worth the possibility of this fault, so go ahead and use it. You won't need the Campden in the RO water since the prefilter in the RO system removes the chlorine compounds for you.

 

[FirstAidBrewing]

Thanks all. I stuck with the campden tablet. FWIW, my water report puts my chlorine at 77 ppm. My last brew was 50/50 my water and RO water.

 

[ajdelange]

That's your chloride.

 

[Qhrumphf]

As has been mentioned, already, chlorine and chloride are different things. Like sulfate and sulfite are different things. Similar words, but they are different chemical compounds. Chloride can often be a good thing in brewing water. Chlorine is never a good thing in brewing water.

My understanding (I'll certainly defer to the experts who've already posted here if I'm wrong) was that the the taste/smell threshold of chlorophenols was well below the taste/smell threshold of chlorine/chloramine. In other words, the level of chlorine/chloramine needed to produce noticeable chlorophenols is low enough that not being able to taste or smell it in your brewing water is not good enough. As mentioned already, campden tablets are cheap insurance.

 

[ajdelange]

Chlorine and chloramine have taste/smell thresholds in the hundreds of parts per billion. Chlorphenolics have taste smell thresholds in the ppb. But not all chlorine/chloramine turns into chlorphenolics so generally if your chlorine/chloramine level is low enough that you cannot smell it in the water chlorphenolics will not form at levels high enough that you can taste smell them. This isn't always the case but I've certainly tasted lots of beers made by my brewing club members using untreated chloraminated water where there is no hint of chlorphenolics. OTOH I have taste quite a few beers where the same water does produce noticeable chlorphenolics.

Part of a Campden tablet is cheap insurance.

 

[mabrungard]

AJ, I've noted the same thing. I have friends in the homebrew and pro ranks that brew without dechlorination and surprisingly, I don't typically note a chlorophenol in some of their beers. Its a real headscratcher as to why chlorophenols can present themselves so prominently in some beers and not others?????

 

[Teesquar]

Sorry for waking the dead, but re-educated myself after reading the water chem primer and will be brewing a batch where my tap water will be cut with RO water.

Should I treat the tap water with the campden before diluting it with the RO or can I just mix the full volume of tap/RO and then add the portioned tablet, figuring it will "seek and destroy" the chlorine?

 

[dyqik]

Sorry for waking the dead, but re-educated myself after reading the water chem primer and will be brewing a batch where my tap water will be cut with RO water.

Should I treat the tap water with the campden before diluting it with the RO or can I just mix the full volume of tap/RO and then add the portioned tablet, figuring it will "seek and destroy" the chlorine?

Either is fine - the metabisulfite will find the chloramine. You should probably portion the tablet by the volume of tap water, but personally I then at least double the dose anyway. The usual dosage can only treat 2ppm chlorine/chloramine, and I've had one batch where the usual dosage wasn't enough.