CO2 increases acidity, changing the taste. Nitrogen doesn't do this. See "chemistry" section of https://en.wikipedia.org/wiki/Carbonated_water https://en.wiki

CO2 increases acidity, changing the taste. Nitrogen doesn't do this. See "chemistry" section of https://en.wikipedia.org/wiki/Carbonated_water https://en.wikipedia.org/wiki/Carbonated_water