I've tested coke/pepsi/RC by random identical cups and I was able to tell, but it was more difficult than I expected it to be. I believe some of that is the way

I've tested coke/pepsi/RC by random identical cups and I was able to tell, but it was more difficult than I expected it to be. I believe some of that is the way your brain works to where, if you believe you know what you are about to eat/drink, it primes you with your memory of the flavors. Going in blind makes it more difficult to do so. To me at least, Coke has more citrus notes and is a bit more sour. RC, at least in the US is slightly more bitter and also seems to have a slightly sweet aftertaste, but not that different from Coke. Pepsi is more sweeter as well, and doesn't have the citrus hit. The more interesting difference is Sugar cane Coke, like they have in Australia, and Corn Syrup. They are both equally sweet, IMO, but the corn syrup has a different aftertaste and texture. Still mostly identical.