An important source of genotoxic agents in the Western diet is the Maillard, or nonenzymatic, browning reaction of amino compounds and reducing sugars. Glutamic acid is one of the most abundant free amino compounds in most foods and, as such, is an important reactant in Maillard reactions. The present study was conducted to examine the mutagenicity of products of the Maillard reaction of monosodium glutamate and glucose in the salmonella mutagenicity assay. The heated mixture was non-mutagenic to Salmonella typhimurium strains TA35, TA37, TA38, TA98 and TA100, in the absence or presence of a rat hepatic microsomal metabolising system. The Authors conclude that reaction products of glutamic acid do not contribute to the mutagenicity of cooked foods