Strictly speaking, seltzer water (or just "seltzer") is a particular type of carbonated mineral water
. The Oxford English Dictionary
defines it as "an effervescent mineral
water obtained near Nieder-Selters, containing sodium chloride
and small quantities of sodium
, and magnesium carbonate
s," or any artificial imitation of that formula. The name comes from the German "Selterser," or "from Seltser," the village in Germany
where springs producing this water were located.
Since this water was reputed to be good for one's health, it was widely exported (and imitated) in the 18th and 19th centuries. An 1881 recipe book gives the process for making your own as follows:
Chloride of calcium and chloride of magnesium of each 4 grs. Dissolve these in a small quantity of water, and add it to a
similar solution of 8 grs. bicarbonate of soda, 20 grs. common salt, and 2 grs. of phosphate of soda. Mix, and add a solution of 1/4 of a gr. of sulphate of iron. Put the mixed solution into a 20-oz. bottle, and fill up with aerated water.
The recipe is followed by a warning that a lot of things sold under the label "seltzer water" were just carbonated
water without anything else special. This is still the case; in fact, "filtered, carbonated tap water
" is how seltzer water is defined in U.S. government water sale guidelines, so apparently it can have other minerals or not.(Seltzer water is considered a soft drink
and does not have to meet the same relatively strict standards as bottled water