Acesulfame-K, ace-K, acetosulfam, Sunett®
Acesulfame is an oxathiazinone dioxide. Chemically, it bears some structural resemblance to saccharin. It is sold as the potassium salt (elemental symbol K), so it often referred to as "acesulfame-K" or "ace-K".
Acesulfame has a sweet taste; many people experience a bitter-metallic aftertaste (much like saccharin). Its onset of sweetness is rapid. The sweetness potency relative to sucrose is about 200, but it depends upon the concentration of sucrose which is being matched.
Acesulfame has good heat stability. Its water solubility is quite good, about 0.3 g per mL.
Acesulfame is a small molecule with high water solubility. It is rapidly absorbed by the body and then rapidly excreted in the urine. Acesulfame has been approved by the United States FDA, the European Food Safety Authority (EFSA), and The Joint Expert Committee on Food Additives (JECFA).
Because of its off taste for some consumers, acesulfame-K is often blended with one or more other sweeteners.