Identification of Novel Orosensory Active Molecules in Cured Vanilla Beans (Vanilla planifolia)

Sequential application of solvent extraction, gel permeation chromatography, and HPLC in combination with taste dilution analyses, followed by LC-MS and 1D/2D NMR experiments, led to the discovery of seven velvety mouth-coating molecules in cured beans of Vanilla planifolia. Among these, 5-(4-hydroxybenzyl)vanillin, 4-(4-hydroxybenzyl)-2-methoxyphenol, 4-hydroxy-3-(4-hydroxy-3-methoxybenzyl)- 5-methoxybenzaldehyde, (1-O-vanilloyl)-(6-O-feruloyl)-β-D-glucopyranoside, americanin A, and 40,60-dihydroxy-30,5-dimethoxy-[1,10-biphenyl]-3-carboxaldehyde were previously not reported in vanilla beans. Sensory studies revealed human recognition thresholds for the velvety mouth-coating sensation between 1.0 and 5.0 μmol/kg (water). Interestingly, the biphenyl derivatives were found to enhance the perception of creaminess and fatty body of sweetened skim milk, among which 40,60-dihydroxy-30,5-dimethoxy-[1,10-biphenyl]-3-carboxaldehyde showed the lowest threshold level of 5 μmol/kg. Quantitative analysis of these compounds in cured vanilla beans from different origins as well as in noncured beans revealed that, with the exception of americanin A, all of the other taste compounds are not present in the green vanilla beans and are formed during the bean curing process