Zotz is a hard candy with a sour, fizzy center that contains sherbet.When bitten into, the candy releases a sour powder that causes a fizzing sensation.Zotz comes in a variety of flavors, including apple, cherry, watermelon, grape, orange, and blue raspberry.The candy’s secret ingredient is a combination of malic and tartaric acids and sodium bicarbonate, which reacts with saliva to create the fizz