SweetN Low sweetener. Coloured scanning electron micrograph (SEM) of crystals of SweetN Low artificial sweetener. This sweetener uses a mixture of Aspartame and AcesulfameK to mimic the taste of sugar (sucrose). Aspartame is a source of phenylalanine, so products must carry a warning as people with the disease phenylketonuria (PKU) are unable to metabolise this amino acid.
