what is seltzer
While seltzer is plain carbonated water and nothing but, club soda usually has a few mineral-y ingredients mixed in for added flavor (see the carbonated water, potassium bicarbonate, potassium sulfate listed on the label directly above vs. the simple carbonated water pictured above that on the seltzer bottle).hile seltzer is plain carbonated water and nothing but, club soda usually has a few mineral-y ingredients mixed in for added flavor (see the carbonated water, potassium bicarbonate, potassium sulfate listed on the label directly above vs. the simple carbonated water pictured above that on the seltzer bottle).