We measured the effects of linoleic and oleic fatty acids on the intensity of sweet, sour, umami and salty tastes. Fatty acids were dissolved in 99.9% ethanol. The dissolved fatty acids were placed in distilled water containing one of four tastants (sucrose, citric acid, monosodium glutamate, sodium chloride) producing a 0.01% fatty acid solution. Using a directional paired comparison test, 30 panelists from the University of Minnesota chose the more intense solution between the fatty acid/tastant solution and a control solution containing only water, tastant and ethanol. Oxidation of the solutions was measured immediately following each sensory test using the thiobarbituric acid reactive substances procedure. Spectrophotometric data demonstrated that no oxidation was found in the fatty acid solutions during the study. Neither linoleic nor oleic fatty acids increased or decreased the intensity of any of the four tastants.