Acesulfame potassium is known as Ace-K, is a synthetic calorie-free sugar substitute  (artificial sweetener),  In the European Union, it is known under the E number (additive code) E950.

Acesulfame K is 200 times sweeter than sucrose (common sugar), as sweet as aspartame, about two-thirds as sweet as saccharin, and one-third as sweet as sucralose.

Acesulfame K is often blended with other sweeteners (usually sucralose or aspartame).  . These blends are reputed to give a more sucrose-like taste whereby each sweetener masks the other’s aftertaste, or exhibits a synergistic effect by which the blend is sweeter than its components, Most often used in: 

Soda

Frozen desserts

Candies

Drinks

Baked goods 

Chewing gum

Sauces‌

Yogurt