Application of headspace analysis to the study of aroma compounds‐lipids interactions

Abstract

Taking into account interactions between aroma compounds and food components is necessary to better manage the flavoring of food products. These interactions occur at a molecular level and reflect changes, at a macroscopic level, in thermodynamic equilibria, such as solubility or volatility. The rate of transfer of an aroma compound from the liquid to the vapor phase can be affected as well. The behavior of aroma compounds in water and lipid solutions was studied in two complementary ways, a thermodynamic and a kinetic approach (headspace analysis). The transfer rate of volatiles at the liquid-water interface does not only depend on the hydrophobicity of the aroma compounds. Vapor-liquid partition and activity coefficients show the presence of solute-solvent interactions. The Gibbs free energy values indicate their physicochemical nature. JAOCS 75, 127-130 (1998).

Temperature effect on solubility of aroma compounds in various aqueous solutions

“…Various aroma compounds constitute the flavoring used in food formulation. The behavior of aroma compounds in both simple and complex media had been largely studied (Solms, Osman-Ismail, & Beyeler, 1973;Solms, 1986;Le Thanh, Thibeaudeau, Thibaut, & Voilley, 1992;Druaux, Le Thanh, Seuvre, & Voilley, 1998;Espinoza-Diaz, 1999;Voilley, Espinosa-Diaz, Druaux, & Landy, 1999;Guichard, 2002). Some of those media included aqueous solutions and emulsions containing major constituents.…”

“…Some thermodynamic equilibrium of aroma compounds in food systems such as partition coefficients between air-liquid phases, liquid-liquid phases and solubility had been reported in literature. Especially, the physicochemical interactions of flavor compounds with water, fat, protein, carbohydrates and emulsifiers had been studied (Druaux et al, 1998;Espinoza-Diaz, 1999;Voilley et al, 1999;Guichard, 2002). These works showed that both components and food structure, may control flavor distribution and release from the different phases of food.…”

An accurate quantitative method for the analysis of terpenes in milk fat by headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry

“…When standards were dissolved in milk fat, the calibration sensitivity for monoterpenes was considerably higher than for sesquiterpenes which were strongly retained in the oily matrix. This occurred because as the solubility of volatile and semi-volatile compounds in a hydrophobic solvent increases, the vapour-liquid partition coefficient decreases (Druaux, Le Thanh, Seuvre, & Voilley, 1998). Another reason to explain this behaviour is that the vapour pressure values at the temperature used in the headspace are higher for monoterpenes than for sesquiterpenes (Fichan, Larroche, & Gros, 1999).…”

Delivery of Flavours from Food Matrices

“…The effect of chain length can be explained by the lipophilicity of the flavour compounds, which is an important factor with respect to the affinity of aldehydes, ketones, esters, thioesters, sulfides and disulfides for the lipid phase (Piraprez et al, 1998;Gijs et al, 2000). Fat concentration (Schirle-Keller et al, 1994) and composition (Druaux et al, 1998), pH (van Ruth et al, 1999) and temperature (Hall and Andersson, 1983) determine the extent of interactions between lipids and small molecules.…”

“…This is the result of the size of the flavour molecule, which differs significantly from that of the solvent molecules and results in repulsive forces. For other compounds in oil, ␥ i values larger than 1 indicate attractive forces between flavour compounds and oil (Druaux et al, 1998).…”