Influence of Linoleic Acid on Taste Intensity Mary Holland Brumbach

Human and rat have an innate preference for fat which may lead to obesity. This preference may be driven by the taste component linoleic acid, the principle free fatty acid found in corn oil. It has been shown that rats are capable of detecting linoleic acid within a solution. It is speculated that rats also perceive an increase in intensity when linoleic acid is added to the solution. This experiment sought to measure the effect on human taste intensity when linoleic acid was added to sweet stimuli. Using a sip and spit method, subjects rated the intensity of a triad, each containing a different amount of linoleic acid (0, 88, or 352 μM) mixed with either sucrose or sucralose (31, 62, 125, 250, 500 mM). There was no effect of linoleic acid on the perceived intensity of the sweet stimuli. However, there was a difference in perceived intensity between the two sweet stimuli. Sucrose was perceived as more intense than sucralose at the 125 and 500 mM concentrations. Body mass index (BMI) and percentage of body fat are two measures of obesity. If taste plays a role in producing obesity, BMI and percentage of body fat would have a positive correlation with taste intensity of sweet stimuli. No correlation was found between either percentage of body fat or BMI and the intensity of the sweet stimuli. Although the current methodology did not measure an effect of linoleic acid, different threshold and discrimination procedures such as forced choice rating system may produce more conclusive data.