Artificial sweeteners are common enough, but bitter blockers are only recently emerging from the laboratory. Salt, sodium chloride is now known to enhance the taste of food by inhibiting various bitterness receptors (of which there are dozens) on the tongue. Monosodium glutamate has a similar action, endowing food with "umami" (deliciousness). Linguagen patented adenosine monophosphate (AMP) as a bitter blocker in 2003 and received regulatory approval a year later. Now, Givaudan Flavors Corporation of Cincinnati reports in the journal Current Biology a compound codenamed GIV3727 that defeats 400 million years of evolutionary protection against ingesting noxious or toxic foods to switch off the tongue's bitter receptors. Major food manufacturers are investigating how to incorporate bitter blockers into products that might otherwise taste off-putting.