Effect of Fat Content on Odor Intensity of Three Aroma Compounds in Model Emulsions: δ-Decalactone, Diacetyl, and Butyric Acid

The purpose of this investigation is to try to explain the odor intensity of three aroma compounds in model emulsions using physicochemical measurements (liquid/liquid partition coefficients and vapor/liquid partition coefficients) and to evaluate how odor intensity is affected by the oil content and the pH of the emulsion. The aroma compounds chosen for this study were diacetyl, δ-decalactone and butyric acid. The physicochemical analyses agree with the sensory data. Hydrophilic molecules (diacetyl and butyric acid) are all the more odorant as the oil content is high. In contrast, odor of hydrophobic molecules (δ-decalactone) is more pronounced in aqueous media. The odor and the vapor/liquid partition coefficient of butyric acid are influenced by pH. This study also provides the means to predict the vapor/liquid partition coefficient of a compound in an oil/water emulsion on the basis of a few physical measurements.