Dynm, i can tell the difference between hfcs and non-hfcs soda. I get blockage near the vocal cords about 5 - 15 minutes after consuming it, so there's definitely something worse than sugar about it.
Sounds like allergy. (I am not a physician. This is not medical advice.)
Difference in trace constituents, triggering allergy, is completely plausible. But either way, it is the fructose identical in both that is actually poisoning you.
I am indeed, i know allergies vs non-allergies. Consider the reactions people have to fried food. You would bin that all under allergies with your logic.
Allergy is defined as an anomalous auto-immune reaction to an introduced substance. Indigestion from a common foodstuff is a good candidate. You would of course need a medical examination to reliably determine that your particular intolerance is allergy. But that's the way to bet.
Difference in trace constituents, triggering allergy, is completely plausible. But either way, it is the fructose identical in both that is actually poisoning you.