Roberts,D.D. and Acree, T.E. 1995
Retronasal Flavor Release in Oil and Water
Model Systems with an Evaluation of
Volatility Predictors
In Interactions Between Flavor and Non-Flavor Conponents. R. McGorrin and J. Leland (Ed.),ACS, Washington D.C. in press
A device was constructed to simulate retronasal aroma incorporating the conditions of salivation, stirring, and air flow that occur in the mouth. Made from a 4 L blender, the simulator was able to handle large sample sizes for increased sensitivity. The volatilities of eight flavor compounds in soybean oil or water were compared, with a calculation of the first-order rate constant, k (min-1). The most volatile compounds in water, a-pinene, ethyl-3-methyl butyrate, and 1,8-cineole had large rate constants of 3.3 x 10 -1, 1.4 x 10-2, and 2.3 x 10 -3 min -1, respectively, which decreased by 2 to 4 orders of magnitude in oil. Two moderately volatile compounds, 2-methoxy-3-methyl pyrazine and butyric acid, behaved differently from each other in oil. Volatility of the pyrazine decreased 7 fold in oil while the acid showed no decrease. The highly non-volatile compounds, methyl anthranilate, maltol, and vanillin, showed low volatilies in both systems. Log P (octanol-water partition coefficients) were measured for the compounds and related to their oil versus water volatilities. Several chemical parameters of the compounds were evaluated for their prediction of volatilities and found to only roughly correlate.