Relationships between Odorant Concentration and Aroma Intensity

Abstract

Aroma intensity of 5 concentrations (0.5, 2.5, 12.5, 62.5, and 312.5 ppm) of dimethyl trisulfide, methional [3-(methylthio) propionaldehyde], linalool (3,7-dimethyl-1, 6-octadien-3-ol), and vanillin (4-hydroxy-3-methoxybenzaldehyde) were evaluated by using sensory panels (n= 15) and gas chromatography olfactometry (GCO, n= 3) coupled with the Osme technique. The exponent (n) from Steven's Power Law was calculated as the slope of the logarithmic scale of perceived intensity versus compound concentration. Both sensory analysis and GCO data demonstrated that all odorants of interest followed Steven's Power Law (R2= 0.92 to 0.99). The relationship between concentration and aroma intensity was more completely explained by Steven's Law than by dilution methods. Results also revealed that GCO-Osme is a time-saving method that provides valuable information about odorants in foods. This method may also be used with other GCO techniques such as combined hedonic aroma response measurement (CHARM) and aroma extraction dilution analysis (AEDA) to more completely explain the contribution of compounds to the flavor of food products.