Burtonizing

I am having a hard time wrapping my head around Burtonizing. From what I understand, "Burtonizing" is loosely defined as the addition of calcium salts (typically gypsum, CaSO4) to balance the calcium hardness and the alkalinity to allow one to brew pale colored beers.

I readily admit that I still have only a cursory understanding of this stuff, and I am probably not thinking about all the variables. I am going to go through my rudimentary understanding and bring up questions. I would greatly appreciate help answering these questions.

From what I can gather from a number of sources, the idea is that balancing the calcium and alkalinity matches the Burton water profile, so that would allow one to hit target mash pH with only light colored malts. But that doesn't make sense to me, since all of that carbonate will (simplistically) keep the pH buffered way too high. There has to be a way to bring down the pH.

I figure there are 2 ways of dropping the pH:

1) Adding acid. There are a number of ways of doing this:
a)Sauermalz - as frequently prescribed by A.J. Delange
b)lactic/mineral acid - same idea as sauermalz, but directly lowers pH of water
c)acid rest - Is this all you would really need, instead of adding extra acid? Or do you only get the desired effect from using certain malts?

2) Precipitating calcium carbonate, a la adding lime to increase calcium concentration. This, from what I understand, will reduce hardness (buffering capacity) and allow the light colored grains alone to drop the pH to desired levels. However, if this were really all that was going on with Burton waters, then wouldn't they have this huge amount of chalk at the bottom of their HLTs all the time? I guess what I am asking is isn't the concentration of CaCO3 in Burton water WAY above the Ksp? How does it stay in solution?

Another way of asking these questions is, if you took real Burton water and only used light crystal malts and base malts and a single-step infusion, would you hit the target pH? Don't you have to use some other techniques (e.g., removing precipitated lime or acid rest) for reducing the mash pH?

dinertime said:

I am having a hard time wrapping my head around Burtonizing. From what I understand, "Burtonizing" is loosely defined as the addition of calcium salts (typically gypsum, CaSO4) to balance the calcium hardness and the alkalinity to allow one to brew pale colored beers.

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There are 2 reasons to "Burtonize". One is to increase the calcium level in the water. This reacts with malt phosphates to release hydrogen ions (acid) and lower mash pH. This is, in effect, neutralizing alkalinity (base). The second reason is to get the high level of sulfate ion which are a characteristic of beers which were traditionally brewed with the waters of that region.

dinertime said:

There has to be a way to bring down the pH.

I figure there are 2 ways of dropping the pH:

1) Adding acid. There are a number of ways of doing this:
a)Sauermalz - as frequently prescribed by A.J. Delange
b)lactic/mineral acid - same idea as sauermalz, but directly lowers pH of water
c)acid rest - Is this all you would really need, instead of adding extra acid? Or do you only get the desired effect from using certain malts?

Click to expand...

d)adding calcium which reacts with malt phosphate precipitating apatite (calcium phosphate) and releasing H+ in the process. That is Reason 1 for Burtonizing.

dinertime said:

2) Precipitating calcium carbonate, a la adding lime to increase calcium concentration. This, from what I understand, will reduce hardness (buffering capacity) and allow the light colored grains alone to drop the pH to desired levels.

Click to expand...

Precipitating calcium carbonate reduces the buffering capacity of the water by removing bicarbonate. It is carbonate system ions that form the buffer. The calcium has nothing to do with it. With reduced alkalinity you can use less acid to get to reasonable mash pH. Adding calcium back in to replace the calcium you precipitate by boiling or lime treatment may be sufficient as the H+ released is better able to neutralize the reduced bicarbonate. Note that Burton water is not very alkaline but is very hard. Thus, even without decarbonation there is enough calcium to overcome the relatively modest alkalinity. As you might expect there is a way of characterizing this relationship between calcium and bicarbonate. It is the Residual Alkalinty you see discussed so widely on these fora.

dinertime said:

However, if this were really all was going on with Burton waters, then wouldn't they have this huge amount of chalk at the bottom of their HLTs all the time? I guess what I am asking is isn't the concentration of CaCO3 in Burton water WAY above the Ksp? How does it stay in solution?

Click to expand...

As I noted Burton water isn't very alkaline and so a modest pH the solution is not supersaturate WRT CaCO3 at room temperature. When I have emulated Burton water (there is a bit more to it than just adding Burtonizing salts) I did get chalk at the bottom of the HLT as soon as I heated it up. And I would expect that to happen in a commercial brewery in Burton if they doughed in with water from an HLT. If, OTOH, they dough in a cooler strike temperature and then raise from there the precipitate would stay with the mash.

dinertime said:

Another way of asking these questions is, if you took real Burton water and only used light crystal malts and base malts and a single-step infusion, would you hit the target pH?

Click to expand...

In theory, no. The Residual Alkalinity is negative and pH is thus not detrimentatlly effected. Most British pale ale malts have a distilled water pH of about 5.6. With negative RA you will obtain a pH a few tenths below this which is fine.

dinertime said:

Don't you have to use some other techniques (e.g., removing precipitated lime or acid rest) for reducing the mash pH?

Click to expand...

Again, theoretically, no but you might choose to add acid (the Brits use a product called CRS which is a blend of hydrochloric and sulfuric acids) to pull pH even lower down to say 5.4 or 5.5.

Please excuse my stream of consciousness ramblings, I am trying to verbalize my train of thought for my own benefit as well as for anyone else who may be following along...

ajdelange said:

There are 2 reasons to "Burtonize". One is to increase the calcium level in the water. This reacts with malt phosphates to release hydrogen ions (acid) and lower mash pH. This is, in effect, neutralizing alkalinity (base). The second reason is to get the high level of sulfate ion which are a characteristic of beers which were traditionally brewed with the waters of that region.

d)adding calcium which reacts with malt phosphate precipitating apatite (calcium phosphate) and releasing H+ in the process. That is Reason 1 for Burtonizing.

Click to expand...

Ok this makes a lot of sense. I was basically oblivious to the role of calcium WRT phosphates.

I was aware of the sulfate effect on hop perception, so I left that part out of my initial post. Am I correct in assuming that that is the only way that sulfate participates (i.e., does not affect pH)?

Precipitating calcium carbonate reduces the buffering capacity of the water by removing bicarbonate. It is carbonate system ions that form the buffer. The calcium has nothing to do with it. With reduced alkalinity you can use less acid to get to reasonable mash pH. Adding calcium back in to replace the calcium you precipitate by boiling or lime treatment may be sufficient as the H+ released is better able to neutralize the reduced bicarbonate. Note that Burton water is not very alkaline but is very hard. Thus, even without decarbonation there is enough calcium to overcome the relatively modest alkalinity. As you might expect there is a way of characterizing this relationship between calcium and bicarbonate. It is the Residual Alkalinty you see discussed so widely on these fora.

Click to expand...

When performing RA calculations, you take the entire Ca and Mg numbers and stick them in. According to Palmer, the calcium reacts with phytin to release protons. I'm pretty sure this is the same thing you said earlier about precipitating apatite. Regardless of exactly what the source is, are we therefore assuming that this phosphate source is always in excess, and the pH-lowering potential of the grain is dependent only on hardness (neglecting for the moment either adjuncts such as sauermalz or the effect of alkalinity)?

If, OTOH, they dough in a cooler strike temperature and then raise from there the precipitate would stay with the mash.

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Because the Ca and Mg in the water react with phosphate in the grist to keep the pH reasonable.

In theory, no. The Residual Alkalinity is negative and pH is thus not detrimentatlly effected. Most British pale ale malts have a distilled water pH of about 5.6. With negative RA you will obtain a pH a few tenths below this which is fine.

Click to expand...

So just to be absolutely clear, Residual Alkalinity is a term made up entirely for brewing, with the understanding that the hardness of the water offsets the alkalinity by reacting with the grain and releasing H+.

Again, theoretically, no but you might choose to add acid (the Brits use a product called CRS which is a blend of hydrochloric and sulfuric acids) to pull pH even lower down to say 5.4 or 5.5.

Click to expand...

Ok that makes sense, just to give it that little bit extra drop in pH if you need it.

Thanks so much! It is beginning to make sense (I think )

dinertime said:

I was aware of the sulfate effect on hop perception, so I left that part out of my initial post. Am I correct in assuming that that is the only way that sulfate participates (i.e., does not affect pH)?

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Sulfate does have an effect on "ionic strength" (as do all other charged ions) and as it is doubly charged has 4 times the effect of, e.g. sodium or calcium ions. Enough gypsum to give 630 ppm sulfate and 147.5 ppm calcium would appear to be different in pH by 0.05 from a water without the gypsum. As that is pretty small, no spreadsheet I'm aware of (except my own) accounts for this as as we seldom deal with that much dissolved mineral, practically speaking, sulfate has no effect on pH.

dinertime said:

When performing RA calculations, you take the entire Ca and Mg numbers and stick them in. According to Palmer, the calcium reacts with phytin to release protons. I'm pretty sure this is the same thing you said earlier about precipitating apatite.

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It is. Phytin is myo-inositol hexaphosphate and is the source of the inorganic phosphate which reacts with calcium and, to a lesser extent, magnesium.

dinertime said:

Regardless of exactly what the source is, are we therefore assuming that this phosphate source is always in excess, and the pH-lowering potential of the grain is dependent only on hardness (neglecting for the moment either adjuncts such as sauermalz or the effect of alkalinity)?

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Malt contains a lot of phosphate (about 2% by weight as the pentoxide) so it's pretty safe to assume that there will be enough for any but the most absurd calcium levels.

dinertime said:

So just to be absolutely clear, Residual Alkalinity is a term made up entirely for brewing, with the understanding that the hardness of the water offsets the alkalinity by reacting with the grain and releasing H+.

Click to expand...

That's it!

dinertime said:

Thanks so much! It is beginning to make sense (I think )

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Great!