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Calling all Chemistry Majors

Alright in sort of a tangled web of root beer making thread I suggested using camden/ meta for reducing chloramines/ chlorine in tap water and it got me to thinking about binding of free SO2 as the PH increases in must. Sorry for the immediate link to the original thread. But if anybody could answer the question I pose within the thread I would greatly appreciate it as it just helps to fully understand the function of Meta as a whole.

Please see the following thread:

viewtopic.php?f=4&t=106274#p939077

You just took all the fun out of making beer for me…I quit!!

Let me cut to the chase and just pose the paragraph/ question within this thread.

“It is interesting that you bring this up because when dealing with wine/ mead/ cider etc… you will have some of the sulfite “bind” depending on PH and this then changes the equation entirely whereas the 90ppm might be total/ free 90ppm in 3.0 must. But in a must at 4.2 ( kinda throwing numbers around loosely) your total/ free might only be 10ppm and you therefore would need to use more to have the total/ free at or above 50ppm. SO If somebody with mad chemistry skills could tell me now will tap water with a PH of 8.7 “bind” any of the ppm like a must would or does it not apply with water itself?”

Just for clarity the question is will sulfur bind in H20 itself the same way it would in any type of must again depending on PH? OR is it just must that will bind sulfur depending on PH due to the multitudes of other compounds within must/s that would not be found in “plain” H2O?

Thank you in advance to anyone that can “get” what I’m saying here.

Pash, sorry your having a bad day dude. Cheer up, drink a brew already.

Add yeast to wort, ferment, carbonate, drink. Simple.

Hey Pash, its interesting that you choose these last couple of days to expend energy commenting on a thread that in all actuality does not even have an ounce of beer or beer making procedure within it. So if a question about the function of Kmeta and PH is enough to drive you bonkers then dont read the thread or comment about it. These questions revolve around wine making, mead making, cider etc…that have a home in this community. You would be surprised that most here are actually curious about topics other than wort, yeast finished.
If you make good beer then keep at it. I choose to expand in this hobby and called on others within the brew community to answer a topic I do not have knowledge in and the wine making portion of the forum will not get my question any answers. That is what is simple.

Totally agree, but you should have posted in the wine section, not All Grain Brewing. :wink:

Free So2 will become Bound due to Volatiles in solution, NOT due to pH.
pH will determine the FREE SO2 level needed for Microbial protection. The higher the pH, the more FREE SO2 required for protection. Further referred to as Storage VS Bottling levels ( .6 VS .8 MOL.) of FREE SO2.
Camden Tablets or Potassium Meta Bisulfite ( K2S2O5) yields approx. one half its weight as SO2 in an acidic solution. This is measured in ppm as Free over Total SO2 with the difference referred to as Bound, i.e. 20/100 ppm, the 20ppm as Free, 100ppm as Total and 80ppm as Bound.
Now, to answer your question. Yes there will be Binding of SO2 in your fairly Alkaline Water, HOWEVER, at that pH level you run the risk of some Reduction to H2S (hydrogen disulfide)
Sorry I didn’t see your posting in the wine making section. But, I have had posting problems in the past.

[quote=“ITsPossible”]Hey Pash, its interesting that you choose these last couple of days to expend energy commenting on a thread that in all actuality does not even have an ounce of beer or beer making procedure within it. So if a question about the function of Kmeta and PH is enough to drive you bonkers then dont read the thread or comment about it. These questions revolve around wine making, mead making, cider etc…that have a home in this community. You would be surprised that most here are actually curious about topics other than wort, yeast finished.
If you make good beer then keep at it. I choose to expand in this hobby and called on others within the brew community to answer a topic I do not have knowledge in and the wine making portion of the forum will not get my question any answers. That is what is simple.[/quote]
Man, I was just messin’ with ya a bit. Relax and have a homebrew.

Tsans-- good info exactly what I was leaning into. Just learned a ton more about this topic from something as simple as going back and forth about root beer of all things. Like the fact that when using Kmeta to reduce chloramines/ chlorine the small amount used will be reduced by the function of the chlorine “scrubbing” action (forgive the non chemist speak, thus the need for clarity in the first place.) I dont know why that never occurred to me.

Another function that makes perfect sense(now) regarding dosing water with high rates of Kmeta (which you never would need to do, But the OP on the root beer was adding 1 tab per gallon to reduce chloramine/ chlorine which is way too high for that function–thus brought me to the question on the table here.) That the formation of H2S becomes a valid topic more than binding. Anybody fancy a good egg drop root beer? just kidding.

Tsans, Can you further explain a possible theory on the full situation( total/bound/free SO2 and possible H2S levels) of lets say adding a campden tablet that is 150 ppm/tab or by weight is .60gram to one gallon of water with 70 TDS/ 51 ALK/ 8.7 PH (If you would need details of a water report I can throw it on in a flash) If not that’s cool as you have answered the question which helps my understanding greatly.

As an aside I did not post this in the wine making forum because it seems like a dead sea in there. I would rather find a chemist that is a brewer or go over to winepress.us or other commercial wine making forums with a techie question like this. So thanks all for the help #1 tsans & #2 we all have something to add at one time or another that’s why I put out the the call to brewers even though it related to “other” topics. So I apologize as it was sort of mis-posted.

Pash, your good people but it seemed as though you were (harshing out man-LMFAO) for no reason thus my comment.

With wine if you get much over pH 4.0 you lose all preservative powers of kmeta. I think it is very much a function of pH rather than binding, although binding does occur as well. Its why when you add kmeta to water for a sanitizing solution, you need to add some acid. Otherwise the metabisulfite doesn’t turn into sulfite, SO2 is the bacteria killer.

You’d have to reduce the sulfite to sulfide in order to get H2S/rotten egg smell. An oxidizer like chlorine won’t do that, it will react and become sulfate.

It may be slow but I see no reason to discredit advice given in the winemaking section on NB’s forum.

Winepress is the best winemaking forum, you’ll get very quick responses there. I always forget to check NB’s wine forum.

Tom, what you said corresponds ( I think - again chemist noob! / I’m learning though, much thanks for your input BTW. ) I think tsans had other thoughts regarding the reduction to H2S. I’m not sure he was referencing to chlorine in that part of his comment. I gathered that he was talking about the alkalinity to some effect.
“HOWEVER, at that pH level you run the risk of some Reduction to H2S (hydrogen disulfide)”

Baratone, no discredit it is what it is. There is and will continue to be good threads within and I continue to seek it out from time to time. BUT when I see you and I and like 2 others giving the majority of the feedback lately then I need to gather my own research in a forum venue such as calling on Brewer/ Chemists as in this one time exception I promise ( Admins dont snuff me out just yet. ) or highly traveled information sources such as winepress or other.

I re-read the thread and I’m not sure what you’re question is. Are you afraid that adding a Campden tab to a gallon of water is going to have some detrimental effect? I would certainly only add one tab to the entire amount of water I was wanting to treat, but theres already proably some sulfate in your water and definitely in your grain/extract (SMM, sulfur-containing amino acids, sulfate). I don’t think theres enough of anything in water to reduce the SO2 to sulfide, but smell it next time you do a treatment and that’ll tell you about sulfide.

Better yet, buy RO water and build your own brewing water. I went away from my tap water because it was inconsistent and had too much sulfate. Its really helped my beer quality.

Tom, being this thread originated from a post revolving around root beer it can be a slight bit confusing to follow I’ll admit that.

Here’s some clarity:
The OP on the root beer thread was adding 1 tab per gallon to remove chloramine/ chlorine which we all know is too high as that one tab is meant for 20 gallons. So this is what sparked my curiosity about the MANY things such as the following.

a. If dosing just plain water (mine for example/ SEPT report) 8.7 PH/ 51 ALK/ 24 CA/ 3 MG/ 17 NA/ 35 CL/ 21 SO4/ 3.65 ppm chlorine what would be the final effect for total/bound/ free SO2 using 1 campden tablet that weighs .60 gram/ 150ppm per tablet to a gallon of the following water? And is it the high PH that still binds portions of the sulfite in solution. ( Now this was preliminarily answered by tsans so I have some better understanding that it is mostly the volatiles in solution of must and that was exactly what I wondered because some of the cider, wine making sulfite calculators/ documents show this in their models, I have included a copy of one or two of the documents I’m referencing to. I fully understand that must itself will be within 2.8 - 4.0 in most cases so the water PH is what I wanted to understand because of how the root beer OP dosed his water. As said somewhere in this thread you would never need to dose water this high its just what spurred the whole question pattern.)

b. Being that tsans raised the issue about the water PH causing the Kmeta/ campden to cause rates of H2S more than the binding of the sulfite then sparked even more curiosity now regarding H2S to become an off aroma/ flavor in the finished root beer as in this case alone. Which brings more understanding of the kmeta/ campden as a whole for me. Please understand this is all worst case scenario learning curve questions not actual process.

c. As you can see in my example above I am in the heart of the St Paul, MN watershed district and feel blessed to have the water I do. I find no issue with it whatsoever other than treating it at .25 tablet per 5 gallons for chloramines/ chlorine and then minor salt manipulations for CA and SO4 and I use a slight amount of phosphoric to lower PH when mashing light SRM beers. Otherwise as stated to new brewers in my area without adjustment most 7-15 SRM beers will hit 5.2-5.5 PH in the mash.

d. I actually just got off the phone with a St Paul watershed lab tech as they have not posted OCT/ NOV water #'s so here are those if anybody is interested.

OCT: 32 CA/ 2 MG/ 17.5 NA/ 40 CL/ 21 SO4/ 55 ALK/ 67 HCO3
NOV: 25 CA/ 5 MG/ 18.1 NA/ 38 CL/ 21 SO4/ 55 ALK/ 67 HCO3

Cant attach the .xls file so here is the link and the I will link the page it comes from if any would like to browse it also it has some good info also about cider.

http://www.cider.org.uk/sulphite_binding.xls

webpage:

http://www.cider.org.uk/sulphite.html

Another good read about this topic from Moorbeer:

http://morewinemaking.com/public/pdf/so2.pdf

e. Like you just mentioned Tom that at/ above 4 PH in a must you either have to use so much as to be unreasonable and also you lose antioxidant properties that you should use acid to reduce the PH to under 3.8 first.

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