Category: sweetener
Aliases: E951, NutraSweet, Equal, Canderel, APM, Aspartyl-phenylalanine methyl ester, L-aspartyl-L-phenylalanine methyl ester, N-L-alpha-aspartyl-L-phenylalanine 1-methyl ester
A dipeptide methyl ester (L-aspartyl-L-phenylalanine methyl ester) ~180-200x sweeter than sucrose, binding the sweet-taste T1R2/T1R3 GPCR heterodimer without activating sour/bitter receptors. It is not absorbed intact: gut-lumen and enterocyte esterases/peptidases (chymotrypsin, carboxylesterases, aminopeptidases) hydrolyse it presystemically to aspartate, phenylalanine, and methanol in roughly 40:50:10 mass ratio. These enter normal metabolism — aspartate transaminated to oxaloacetate (TCA cycle), phenylalanine into the body amino-acid pool, methanol oxidised via alcohol/aldehyde dehydrogenase to formaldehyde then formate. Being non-glycaemic it does not raise glucose or insulin. Heat-labile, so it is unsuitable for prolonged baking. Approved as a table-top and food-additive sweetener.
E951; ~180-200x sweeter than sucrose. JECFA/EFSA ADI 40 mg/kg/day (FDA 50 mg/kg/day). Contains phenylalanine, so contraindicated in phenylketonuria (PKU) — mandatory label warning. IARC classified it as possibly carcinogenic (Group 2B) in 2023 while EFSA/JECFA reaffirmed it safe within the ADI.