Purple Thunder is a Berry Plum (Blackberry Plum) flavor of Mountain Dew, and its name implies a purple color.  
 
Imported From USA
 
INGREDIENTS
CARBONATED WATER, HIGH FRUCTOSE CORN SYRUP, CITRIC ACID, NATURAL AND ARTIFICIAL FLAVOR, SODIUM BENZOATE (PRESERVES
FRESHNESS), CAFFEINE, SODIUM, CITRATE, GUM ARABIC, CALGIUM DISODIUM EDTA (TO PROTECI FLAVOR), RED 40, BLUE 1.