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be ition lino to a than 20 % of Americans [11,35,39]. In 2000, obesity was the [7,30,31,52]. Surprisingly, little research has investigated the source of salient sensory perceptions underlying the high post-ingestive feedback [34]. Corn oil is preferred to control Additionally, ZnSO4 nasal treatments to block olfactory cues do not diminish the corn oil preference and anosmic rats are ferences using corn uli [48]. Physiology & Behavior xx (2 + modelpalatability of dietary fat.second leading cause of American deaths accounting for>20% of deaths resulting from modifiable behavioral risk factors [36]. In addition to genetic traits [1,10,45,46,51], poor diet [8,6,30– 33] coupled with physical inactivity [3,40,47,50] have been identified as the principal contributors to obesity [36]. A strong association exists between obesity and high daily intake of dietary fat [30,32,33] with increased palatability cited as the primary motivation for the over-consumption of dietary fat solutions of either mineral oil or xantham gum providing evidence that texture is not the salient orosensory cue [9,16,34,42,48]. Conditioned taste aversions (CTAs) to sucrose–corn oil mixtures produce a stimulus generalization to a sucrose–linoleic acid mixture, but do not generalize to a sucrose–mineral oil mixture [44] suggesting that the salient feature is a non-textural, orosensory cue elicited by the free fatty acid (FFA) constituent of corn oil, linoleic acid.properties. Furthermore, it is unlikely that the detection of the FFAs is due to an enhancement of other concomitant tastants such as saliva or the delivery solution