SUMMARYFollowing a request from the European Commission, the Scientific Panel on Food Additives, Flavourings, Processing Aids and Materials in Contact with Food (AFC) was asked to deliver a scientific opinion on the safety of neotame as a sweetener and flavour enhancer.Neotame is a dipeptide methyl ester derivate. Its chemical structure is N-[N-(3,3-dimethylbutyl)-L-α-aspartyl]-L-phenylalanine 1-methyl ester. It is intended for use in food as a sweetener and flavour enhancer. Neotame has a sweetness factor approximately 7000 to 13000 times greater than that of sucrose and approximately 30 to 60 times greater than that of aspartame, depending upon the food application.Neotame is manufactured by the reaction of aspartame and 3,3-dimethylbutyraldehyde, followed by purification, drying, and milling. Neotame is generally stable under conditions of intended use as a sweetener across a wide range of food and beverage applications.
Neotame as a sweetener and flavour enhancerThe EFSA Journal (2007) 581, are not detected at the anticipated concentrations and conditions of neotame use in carbonated soft drinks.At least 30% of neotame ingested is rapidly absorbed in all species. The major metabolic pathway is de-esterification by non-specific esterases to NC-00751, which accounts for approximately 80% of the neotame dose as NC-00751 in all species tested. Peak plasma concentrations of neotame and NC-00751 are observed at approximately 0.5 hours and within 1 hour, respectively. Neotame is completely eliminated from the body with recovery in urine and faeces exceeding 98% in the human and greater than 93% in the rat and the dog within 72 hours. The majority of radioactivity is excreted in faeces in all species. The major component in the faeces is NC-00751.Studies with radiolabelled neotame given orally to rats indicate no accumulation in tissues. The highest radioactivity is associated with the contents of the gastrointestinal tract and organs of metabolism and excretion (liver, kidney, urinary bladder). In whole body autoradiography studies with pregnant rats no radioactivity has been reported in the fetus.The safety of neotame has been investigated in in vitro studies and in short and long-term studies in mice, rats, rabbits and dogs. The results indicate that neotame is not genotoxic, carcinogenic, teratogenic or associated with any reproductive/developmental toxicity. The consistent findings in animal studies were reduced feed consumption, body weight and body weight gain relative to that of controls, with no clear dose response. These effects are considered not adverse or indicative of toxicity but a consequence of reduced palatability of the neotame-containing diets. Therefore body weight parameters were not considered appropriate endpoints for setting no-observed-adverse-effect levels (NOAELs) in these studies.A consistent finding was an increased activity of alkaline phosphatase (AP) of hepatic origin in dogs in the 13-week study at doses of 600 and 1200 mg/kg bw and in the 52-week study at 800 mg/kg bw. In the lat...