I suspect by the time the Malnatis get Lake Michigan water to their restaurants, it has gone through a lot of processing

. I have never used the municipal water where I live for making pizzas. Since I wouldn't drink the stuff, I decided that I wouldn't use it for pizza. Maybe I was a bit rash. I think I will give it a try, just to see what results I get and whether I should mend my ways

. I would have no reservations whatsoever about using NYC municipal water for making pizza dough. It's the best city water I have ever tasted and its drinkability came to me as a shock since I would never have imagined that a city as large as NYC and so heavily populated could produce water that is so good tasting. Maybe that's what perpetuates the NY water myth.
I'm sure the bottled water I use is missing some good things. Professional pizza makers who are concerned about the quality of the water they use look mainly at the mineral content (mainly calcium and magnesium) and the pH (percentage of hydrogen ions) of the water. The mineral content (and hardness/softness) is important since the minerals act as nutrients for the yeast. Tests indicate that the best fermentation rate is produced when the water hardness is 125-150 parts per million.
pH--a measure of the degree of acidity or alkalinity of a solution--is important to dough-making because it affects the chemical and biological reactions, most notably the conversion of starch to sugar (maltose) to feed the yeast and make the dough rise. The optimum pH for pizza dough is considered to be around 5.0 (or slightly acidic). This pH level is best achieved by using water that has a pH in the range of 6.5-8.0, with a pH of 7.0 (neutral) being the optimum. If the pH is too low (high acidity), it can inhibit fermentation activity. In Naples, where the water is filtered through volcanic deposits, the pH is 6.7.
I will have to see if I can dig up my municipality's water report to see if my water meets all of the above requirements

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Peter