Maxwell Colonna-Dashwood's water article in Barista
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DavidMLewis
- Posts: 590
- Joined: 19 years ago
In the current issue of Barista, on page 74, there is an article by Maxwell Colonna-Dashwood about water that I found interesting. In it, he opens a line of research into the binding energies of various components of common water supplies, as well as into the effect of bicarbonates. It is the only thing I have seen that correlates with observed changes in flavor as hardness increases. I would love to hear the opinions of those such as Jim whose knowledge dwarfs my own.
Best,
David
Best,
David
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another_jim
- Team HB
- Posts: 13961
- Joined: 19 years ago
It's a good article with no nonsense and some new ideas. So my comments are more questions than criticisms.
The point made about the different catalytic (or extraction assisting) affects of magnesium and calcium are new to me. It should be a result that can be repeated in a blind taste test.
The account that very hard waters contain enough carbonates (alkalinity) to buffer the acids in coffee has some elements that need confirmation. First off, it envisions that very hard water contains unusually high proportions of carbonates. That would require it to contain a balancing amount of other cations -- potassium, sodium, or metals for instance, rather than calcium or magnesium. Is this generally true? It is true of salt softened water which replaces the calcium with sodium but leaves the carbonates; but is it true of natural waters?
The other question is how do the raised levels of carbonates get into the brewing water. When natural water is heated, the carbonates scale out very quickly. How hard is the water coming out of an HX or out of a brew boiler? In the water FAQ, I made the simplifying assumption that the excess minerals left the water immediately on heating, and formed scale. This means hard water is a scaling prolem, not a brewing one. You cannot brew with too hard water, since 90C water at equilibrium is neutral, not hard. This may be true with a brew boiler, or a Zoshirushi dispenser; but it may not be true of quickly heated brew water.
The only time one can assuredly get very high carbonates in brew water is if the water is cation softened; at which point the carbonates remain soluble. Very hard water that is cation softened does dull the cup; this has been observed repeatedly. The article suggests that some areas have natural water that has the same effect, at least when using the brew methods they did.
The point made about the different catalytic (or extraction assisting) affects of magnesium and calcium are new to me. It should be a result that can be repeated in a blind taste test.
The account that very hard waters contain enough carbonates (alkalinity) to buffer the acids in coffee has some elements that need confirmation. First off, it envisions that very hard water contains unusually high proportions of carbonates. That would require it to contain a balancing amount of other cations -- potassium, sodium, or metals for instance, rather than calcium or magnesium. Is this generally true? It is true of salt softened water which replaces the calcium with sodium but leaves the carbonates; but is it true of natural waters?
The other question is how do the raised levels of carbonates get into the brewing water. When natural water is heated, the carbonates scale out very quickly. How hard is the water coming out of an HX or out of a brew boiler? In the water FAQ, I made the simplifying assumption that the excess minerals left the water immediately on heating, and formed scale. This means hard water is a scaling prolem, not a brewing one. You cannot brew with too hard water, since 90C water at equilibrium is neutral, not hard. This may be true with a brew boiler, or a Zoshirushi dispenser; but it may not be true of quickly heated brew water.
The only time one can assuredly get very high carbonates in brew water is if the water is cation softened; at which point the carbonates remain soluble. Very hard water that is cation softened does dull the cup; this has been observed repeatedly. The article suggests that some areas have natural water that has the same effect, at least when using the brew methods they did.
Jim Schulman
