thomcat333
Well-Known Member
I like chemistry, so I've been working on building up (or down) my local water to suite my brewing purposes. I downloaded our local water report to get a baseline and began calculating additions from there.
Preface: this question/observation only concerns additions affecting hardness and carbonate levels. Sulfate, sodium, chloride, and other taste-affecting ions aren't really covered b/c that's not part of my question.
I've listed below the traditional brewing waters with some chemical data. By using the bicarbonate (HCO3), calcium (Ca), and magnesium (Mg) concentrations, one can calculate the alkalinity (in equivalents of CaCO3) as well as the hardness (also in equivalents of CaCO3). Please note that neither of these are concentrations of CaCO3. It's just a way of expressing the data.
Going on...
Alkalinity is (in tap water) primarily a function of the bicarbonate (HCO3) and carbonate (CO3) concentrations. These are the conjugate bases of carbonic acid and part of the carbonic buffering system. The more carbonate and bicarbonate you have, the more acid can be introduced without changing the solution pH as much... hense... the term buffer.
Hardness relates to the calcium (Ca) and magnesium (Mg) concentrations. These ions help to counteract the basic buffering properties of carbonate and bicarbonate by becoming associated with them via charge-charge interactions, not allowing them to accept more H+ molecules (acid).
Here's my observation/question.
Since higher alkalinity helps neutralize acids, and hardness helps counteract that effect.... shouldn't the ratio of hardness to alkalinity be a good design variable? (given the fact that acidity and grain roast level are roughly proportional)
To test this, I charted the traditional brewing waters below in order of this ratio. It seems to make sense that the lowest hardness to alkalinity ratio is Dublin. That means that Dublin should have more alkalinity per hardness and therefore be able to neutralize more acid. And, sure enough that water naturally makes the darkest beers well (using dark roasted acidic grains). The reason that the acid needs to be neutralized somewhat is to keep the mash pH near it's sweet spot between 5.0 and 5.5.
So... I've started building my water based on the hardness to alkalinity ratio. And so far so good. Any thoughts? or flames? It's okay, my feelings won't be hurt. Just looking for input/dialogue.
Cheers!
Preface: this question/observation only concerns additions affecting hardness and carbonate levels. Sulfate, sodium, chloride, and other taste-affecting ions aren't really covered b/c that's not part of my question.
I've listed below the traditional brewing waters with some chemical data. By using the bicarbonate (HCO3), calcium (Ca), and magnesium (Mg) concentrations, one can calculate the alkalinity (in equivalents of CaCO3) as well as the hardness (also in equivalents of CaCO3). Please note that neither of these are concentrations of CaCO3. It's just a way of expressing the data.
Going on...
Alkalinity is (in tap water) primarily a function of the bicarbonate (HCO3) and carbonate (CO3) concentrations. These are the conjugate bases of carbonic acid and part of the carbonic buffering system. The more carbonate and bicarbonate you have, the more acid can be introduced without changing the solution pH as much... hense... the term buffer.
Hardness relates to the calcium (Ca) and magnesium (Mg) concentrations. These ions help to counteract the basic buffering properties of carbonate and bicarbonate by becoming associated with them via charge-charge interactions, not allowing them to accept more H+ molecules (acid).
Here's my observation/question.
Since higher alkalinity helps neutralize acids, and hardness helps counteract that effect.... shouldn't the ratio of hardness to alkalinity be a good design variable? (given the fact that acidity and grain roast level are roughly proportional)
To test this, I charted the traditional brewing waters below in order of this ratio. It seems to make sense that the lowest hardness to alkalinity ratio is Dublin. That means that Dublin should have more alkalinity per hardness and therefore be able to neutralize more acid. And, sure enough that water naturally makes the darkest beers well (using dark roasted acidic grains). The reason that the acid needs to be neutralized somewhat is to keep the mash pH near it's sweet spot between 5.0 and 5.5.
So... I've started building my water based on the hardness to alkalinity ratio. And so far so good. Any thoughts? or flames? It's okay, my feelings won't be hurt. Just looking for input/dialogue.
Cheers!