This is a nice legend about the secret recipe. However production differs oflver the world. I.e. I'm the US the sweetener is high fructose corn syrup, while Europe uses Sycrose.
(anyone know specifically why the sweetener differs? I'm guessing either cost or legislation...)
http://www.motherlindas.com/HFCS_murky.htm
https://grist.org/article/adm-high-fructose-corn-syrup-and-e...
https://youtu.be/gPbh6Ru7VVM (skip to 5:30)