I have tried several types of bottled water, from Aquafina, Deerpark, etc.. in the US, to Sapporo Nihon meizan no tennensui, Asahi tateyama..., etc... to France based Volvic and one of those offbrands sold at Carrefour that is basically Volvic in a different label...
And my determination is that the Japanese water is tap... all the Japanese brands I have tried taste like tap water. Today I and my wife tried a taste test and I couldn't tell the difference between the tap water and the Japanese Sapporo bottled water....
Are there any standards? Tests? I mean when I drink volvic *which I think is pretty good for a pet bottle mineral water, I can tell a huge difference in the cleanliness of the water... With the Japanese water it's got like an extremely mild sulfur taste or something.
Could it be that the waters are just different types like hard and soft water? Or is it that Japanese water has different minerals?
I swear though that the tap and bottled water taste differently to me... compared to foreign bottled waters like Evian, Crystal Geyser, Volvic, etc....