I can only say Coca Cola taste the same in The Netherlands, Germany, and Vietnam. While I can generally tell quite well when I get a different cola then a Coca Cola one. Based on that there should be some kind of international standard?
I can imagine US being different due to less strict rules around food than EU (much American junkfood is altered in the EU market due to this). But then I'm suprised Vietnam taste the same for that same reason π€.
I generally drink Zero. If the sugar is the different, could that be why?
Zero taste the same as regular to me but less sweet, but since I rarely drink regular I don't have the exact taste of that in my mouth.