Chloramine and Potassium Metabisulfite

[Mikeyr]

If you are worried about Metabisulphite then you can also use ascorbic acid to neutralise chlorine and chloramines
http://www.beeradvocate.com/community/threads/vitamin-c-for-chlorine-chloramine-removal.76953/

Ok guru's go at it! I prefer the idea of vitamin c over camden tabs. Too many old hiking and cross country skiing water treating , ****** tea tasting memories. Even knowing that in the doses we are talking about should be impossible to discern.

 

[Lyrebird_Cycles]

The reaction in this case is 1:1, so the application ratio is 3.4 : 1 for ascorbic acid (176.1 g/mole vs 51.5 for chloramine) and almost 4:1 for sodium ascorbate (198.1 g/mole). Accordingly, if your water has ~ 2 mg/l chloramine, you'd need to add 7 mg/l ascorbic or 8 mg/l sodium ascorbate.

Trouble with this is that if you want to treat say 20 litres of water you'd need to add 140mg ascorbic and unless you're a drug chemist that's probably hard to do accurately. You could make up a stock solution but ascorbic is notoriously unstable in solution so you'll need to stabilise it. Ironically the standard way to do this is to add metabisulphite and adjust the pH to around 5. Store the solution in a glass bottle in the fridge, preferably after purging the headspace. Plastics like PE are permeable to oxygen.

An easier way to stabilise it would be to make it up at double strength and cut it 50% with commercial lemon or lime juice.

 

[peteru]

Scales with 0.1g resolution are not difficult to get for a few bucks from eBay. Ascorbic acid is easy to get too, and cheap, so you could make a solution, use what you need immediately and discard the rest.

Or even better, rather than discarding, just mix with a bit of fruit juice for flavour and drink it.

 

[Mikeyr]

Scales with 0.1g resolution are not difficult to get for a few bucks from eBay. Ascorbic acid is easy to get too, and cheap, so you could make a solution, use what you need immediately and discard the rest.

Or even better, rather than discarding, just mix with a bit of fruit juice for flavour and drink it.[f/quote]

Yep have some, usually measuring grains (the unit of measure, not malt, one by one) food for thought

 

[MHB]

Yes but 0.1g is 100mg, so if the scales are saying 0.1g the real weight on them is over 0.05g and less than 0.15g and another 0.01 of a g and the scales will say 0.2g.
Weighing 140mg on 0.1g dealer scales is giving you something like a 50% error, not really up to snuff.
Good rule of thumb is that scales need to have one more place than you are using, so if you wanted to measure 0.14g accurately you should have 0.001 resolution. In this case 0.01 would do, for production work, but not for R&D.
Mark

 

[peteru]

I was thinking of measuring out something like 2.8g and dilute in 200g of water. You end up with a solution that has 1,400mg/100g. Use 10g of the solution to get your 140mg dose. The margin of error for the intended purpose (i.e treating brewing water where the chloramine content is guesstimated) is perfectly acceptable.

If you are going to do R&D work, you are very likely to have the equipment and skills already.

 

[Lyrebird_Cycles]

Mark, I know that the action of dehydroascorbic acid as an electron carrier enhancing oxidation can be a problem in finished beer if there's not enough SO2 present, what I don't know is whether the dehydroascorbate produced by the reduction of the chloramine will end up in the beer.

I've checked through both Briggs and Priest and there's no metion of this, do you know of any up to date research?

 

[MHB]

I spent a bit of time last night looking at a few related questions.
Where the question lies for me is that the chemical Cl removal methods other than activated carbon filters all rely on pretty powerful Antioxidants. How sure are we that the antioxidants are reacting with Cl exclusively and that some of it isn't consuming dissolved O2, and leaving some of the Cl behind.

In a commercial brewery, water is likely to be filtered, carbon filtered to remove halides and other organic chemicals, de-aired, then adjusted to suit the water chemistry requirements of what is being brewed.

I'm a little concerned that we are talking about just chucking in various chemicals in what is going to amount to a fairly random way - without any way to monitor the effectiveness of the process.

If there is a surplus of quite powerful antioxidants how will they affect the beer? (see LC above) short answer is I don't know, there appears to be a real shortage of pro/research brewers tossing these type of chemicals into their beer and talking about it! Maybe there are bashful or just chagrin but they ain't talkin.

If you have issues with Cl/NH2Cl, I think at this point I would filter (get the right carbon it will remove NH2Cl). Or boil and de-air my brewing water - all pretty low tech but known to be effective without the potential for unknown side-effects.
Mark

 

[Lyrebird_Cycles]

How sure are we that the antioxidants are reacting with Cl exclusively and that some of it isn't consuming dissolved O2, and leaving some of the Cl behind.

Pretty sure: the reactions with chlorine and chloramine are highly preferential.

The result of this experiment is fairly conclusive*: even in the presence of 50 ppm free chlorine, the addition of ascorbate removed the chlorine in preference to the O2.

Further to your other comments: Ion exchange or RO are commonly used in large breweries for water amelioration. RO will remove chloramine but not necessarily chlorine, which can diffuse across the membrane as a gas. The other thing that works in their favour is that the strike liquor is made up mostly of the output of the wort heat exchanger from the previous brew, so it's spent some time at an elevated temperature.

*Apart from the fact that they wrote chloride when they meant hypochlorite.

 

[MHB]

And they can afford to measure Cl in any form and dose accordingly.
My main concern is that if we are told the typical concentration (subject to change at the water authorities need) at the water treatment plant, that wont necessarily be what we get at the tap, so most people will be over dosing leaving residual anti oxidants in the brewing water.

Even without RO or a way to measure Cl, there are pretty well proven ways to remove Cl (and most O2) fairly easily at a home brew scale without the undefined possibilities of tossing in chemicals that we don't really know the effect of on our beer.

Mark

 

[Mikeyr]

Now I'm getting confused, since we are pre-boil aren't we trying to not to aerate/oxygenate the mash? So any 02 reduction isn't a "biggie"

"Tossing in chemicals" seems a bit harsh when all we're discussing is how to get chloramine out, by using a quarter of a standard vitamin c tab in 23 litres of liquid! And won't the boil process destroy the majority of lingering ascorbic acid in any case?

Oh and on scales .....grain not grams was my comment. 1 grain is about 60mg from memory and we measure to 0.1 gr. level. So yeah plus or minus .05 gr / 3mg.

 

[Lyrebird_Cycles]

won't the boil process destroy the majority of lingering ascorbic acid in any case?

That's the point: the immediate breakdown product of ascorbic acid is dehydroascorbic acid, which is an electron donor and will thus initiate free radical formation*. Dehydroascorbic will further breakdown to diketoglutaric acid and oxalic acid, neither of which will cause such problems.

My question was how far this reaction went in wort. Excess dehydroascorbic is a known problem in beer, causing oxidation in package.

The breakdown product of SO2 is sulphate, so the addition of PMS is very unlikely to cause any problems.



* in the presence of metal ions and the absence of scavengers such as SO2. These conditions are often met in beer post packaging.

 

[MHB]

Now I'm getting confused, since we are pre-boil aren't we trying to not to aerate/oxygenate the mash? So any 02 reduction isn't a "biggie"

"Tossing in chemicals" seems a bit harsh when all we're discussing is how to get chloramine out, by using a quarter of a standard vitamin c tab in 23 litres of liquid! And won't the boil process destroy the majority of lingering ascorbic acid in any case?

Oh and on scales .....grain not grams was my comment. 1 grain is about 60mg from memory and we measure to 0.1 gr. level. So yeah plus or minus .05 gr / 3mg.

Agreed lots of difference between g and gr and an order or two better, they would be fine, fair to say that the use of grain weight wasn't implicit in your post.
Disagree that I was being harsh, we are talking about removing a chemical that is/can cause problems in brewing at very low levels, there isn't much there and we don't need much to neutralise it.
But we need to know that the cure isn't worse than the problem - I suspect sub gram dosed of the chemicals discussed wont cause any problem, tho we know for a fact the same amount of Chloramine will - at this point "I suspect" I don't know and my only concern is to know what is happening and that we just aren't replacing one problem with another.

As above we could just boil/heat our water before use, with some care we could be reducing/eliminating Cl, Cl-amines, O2 and temporary hardness all in the same step, a well tested method that we know the effects of without any downsides except for time and energy cost.
Just cautioning that before we embrace a whole new approach to replace a proven existing one we understand the consequences.
Mark

Edit Just went out for smoke think
If as LC says (not questioning it) Ascorbic acid ends up being broken down into Oxalic Acid, I would have to be taking a long hard look at how much was ending up in my beer, it takes 3-4 Ca to remove Oxalates and if that doesn't raise a question or two you need to google the role of Oxalates in the formation of beer stone and gushing in packaged beer, then take a another long hard look at your water chemistry and the amount of available Ca in there.
I will now have to sit down and play with the numbers - just assuming can lead to some unexpected outcomes...
Often not in a good way.
M

 

[Lyrebird_Cycles]

After a bit of further reading I think I can answer my own question.

It appears that ascorbic in the presence of amino acids and heat will participate in non-enzymatic browning reactions, possibly via furfural. Apparently this is a problem in heat treated orange juice, who knew?

It therefore seems unlikely that anything untoward will end up in the beer.

 

[BKBrews]

Reading this thread, am I safe to assume that a pre-brew day boil of my water and half of a vitamin c tablet while I'm at it will be a major improvement over the brews I've done on my standard supply?

 

[Adr_0]

Reading this thread, am I safe to assume that a pre-brew day boil of my water and half of a vitamin c tablet while I'm at it will be a major improvement over the brews I've done on my standard supply?

Yes. Congratulations!