(Warheads Extreme Sour Hard Candy derive their strong sour flavour primarily from malic acid which is applied as a coating to the outside of the small, hard sweeties. The intense sour flavour fades after about 20 to 40 seconds. The sweet itself contains the somewhat less sour ascorbic acid and citric acid, but at the centre of the boiled sweet is a small pocket of more malic acid. I wonder what part of “sweet” they don’t understand.)
Warheads are the world’s sourest sweets.