STUDY OF AROMA COMPOUND-NATURAL POLYMER INTERACTIONS BY DYNAMIC COUPLED-COLUMN LIQUID-CHROMATOGRAPHY

Dynamic coupled column liquid chromatography (DCCLC) was used to study the interactions between the model aroma compounds beta-ionone and limonene and the model food components dextrin and soya bean trypsin inhibitor. Solutions saturated with aroma compound can be obtained by a dynamic and reversible process. Interactions between the two categories of molecules were evidenced using exponential dilution and DCCLC, and the reversibility of the complex formation between limonene and trypsin inhibitor was established. The association constants K-a calculated for the complexes dextrin-limonene and trypsin inhibitor-limonene were 13 650 +/- 250 and 2 944 +/- 784 M(-1), respectively. The decrease of the calculated K-a values when beta-ionone and dextrin are used is indicative of an irreversible adsorption of beta-ionone on dextrin whereas a weak interaction, K-a = 385 +/- 105 M(-1) is obtained in the presence of trypsin inhibitor.