Just out of curiosity, was this #3 and you didn't have enough citric or something?
Just some fun facts:
POWERADE Cherry- Ingredients: Water, Glucose, Fructose, Citric Acid, Sodium Chloride, Fruit and Vegetable Concentrates (Chokeberry, Elderberry, Sweet Purple Potato, Safflower, Radish), Acidity Regulators (Potassium Citrate, Magnesium Chloride, Calcium Chloride, Potassium Phosphate), Stabilisers (Acacia Gum, Glycerol Esters of Wood ...
Without getting into the vegetable concentrates, the stabilisers, like Acacia gum or Glycerol Esters of Wood might cause it to thicken, just one problem being ischemia in smaller vessels like lungs if your liver & kidneys can handles the rest.
Now if you are a POWERADE- Fruit Punch man:
Ingredients
WATER, HIGH FRUCTOSE CORN SYRUP, CITRIC ACID, NATURAL FLAVORS, SALT AND MAGNESIUM CHLORIDE AND CALCIUM CHLORIDE AND MONO-POTASSIUM PHOSPHATE (ELECTROLYTE SOURCES), MODIFIED FOOD STARCH, GLYCEROL ESTER OF ROSIN, CALCIUM DISODIUM EDTA (TO PROTECT COLOR), MEDIUM CHAIN TRIGLYCERIDES, VITAMIN B3 (NIACINAMIDE), VITAMIN B6 (PYRIDOXINE HYDROCHLORIDE), VITAMIN B12 (CYANOCOBALAMIN), RED 40, ASCORBIC ACID (TO PROTECT TASTE.
With this one, the MODIFIED FOOD STARCH, GLYCEROL ESTER OF ROSIN,MEDIUM CHAIN TRIGLYCERIDES stand out as the Jello-matic ingredients that respond very poorly to heat. I've never imagined myself saying this, but Sodium Benzoate would have been a plus.