Water Addition Advice - 1st AG Batch

[WoodlandBrew]

It was more comment on the use of the word "science" than anything else you wrote. I disagree with a lot of the conventional homebrewing water chemistry wisdom - specifically the concept of RA and as someone who lives in a place that RO flows from the taps, i have to question the minimum ion concentrations that are often quoted. ...and yeah...the classic city stuff is complete fantasy (unreferenced fake history, BS styles, impossible profiles) and won't help you brew any better.

Agreed on MgSO4, NaCl and NaHCO3. Get the lowest carbonate water and supplement the Ca with CaCl and CaSO4. Yeast nutrient can provide anything else you need. If you were brewing huge commercial batches of the same recipe with the same malt every day, you might be able to dial in your water profile perfectly but as a homebrewer doing 5 gallon batches with different malt and different recipes every time I brew I don't believe its possible to anything better than just ball park (vs the 2 decimal pts the spreadsheets calculate to). Your daily water profile isn't accurately known, the margin of error measuring salts is too great, different malts will behave differently, etc

I don't understand residual alkalinity well enough to really have an opinion on it, but other than that small exception I agree with you 100%

 

[mabrungard]

GBX has it correct that there are too many variables in all the ingredients used in brewing to assume that any program or prediction is going to be precise. Getting within a tenth with a pH prediction starts to border on luck with all that ingredient variability. Showing predictions with a precision in the hundreths is folly. I do disagree with GBX that this is more art than science. There is more than enough evidence and knowledge to show that it is FAR more a science than art. The art comes in deciphering the nuances that make great beer. The proper application of science will at least get you in the ballpark.

Magnesium is unnecessary in brewing water. The malt provides magnesium to the wort. But, this is not to say that you shouldn't use it. In beers that focus on bittering and hoppiness, I find that Mg is a welcome compliment when used at low concentration. Its sour and bitter flavor fits in those bitter beers and adds character. I do keep Mg at 30 ppm or less in those beers.

The confusion with chloride is the result of an unfortunate reference in How to Brew. It cites the Secondary Standard for drinking water that lists the recommended allowable chloride concentration as 250 ppm. That is the point where the drinking water becomes unpleasant or undesirable to drink. It is not an acceptable target for brewing good beer. ALL the notable brewing waters of the world have less than 100 ppm Cl. A notable exception is Dortmund water that is known for its 'minerally' character (130 ppm). Therefore, its clear that history shows that 250 ppm is not an acceptable or desirable upper limit.

The concept of the sulfate/chloride ratio has some merit. The problem comes when brewers try to apply it under all conditions. When the concentrations of those ions are either very high or very low, the ratio is meaningless. I recommend that brewers consider the ratio valid when the chloride concentration is between 25 and 100 ppm.