A study of the solution properties of selected binary mixtures of bulk and intense sweeteners in relation to their psychophysical characteristics

The solution properties of binary mixtures of two bulk sweeteners (sucrose and maltitol) and three intense sweeteners (acesulfame K, aspartame and sodium cyclamate) were studied. The parameters measured were apparent specific volumes, isentropic compressibilities and compressibility hydration numbers. An attempt has been made to correlate the solution properties of some of the mixtures with their sweetness responses. Both specific volume and isentropic compressibility data have been used to interpret the possibility of synergism or suppression in the mixtures in terms of the affinity of the solutes for the surrounding solvent structure, and hence the effectiveness of transport of the molecules to their appropriate receptor sites. However, an understanding of the nature and stereochemistry of the individual components in the mixtures is necessary for predicting the packing characteristics of molecules in water and their accession to receptor sites. The intense sweeteners seem to play an important role in modifying the structure of water in solution. Although there is no clear proof of how this affects perception, fine differences in solution behaviour can be observed with isentropic apparent specific compressibility measurements. The study supports the idea that receptors lie at different depths in the lingual epithelium, and also that in two-component systems, one species may alter the packing efficiency of the other in solution sufficiently to effect a change in taste quality or intensity.