Sensory and chemical analysis of fractions obtained by gel permeation of water-soluble Comte cheese extracts

The pure water extraction of Comte cheese solubles and their chromatographic separation facilitate sensory analysis experiments with the fractions directly collected from the column. Two extracts, one obtained after ultrafiltration, the other after chromatography on Sephadex G25, have been separated on Toyopearl HW-40S. The sensory evaluation of the obtained fractions shows in the two cases that some fractions have interesting flavors. However, physicochemical analysis shows that organoleptic characteristics are linked more to the presence of amino acids and salts than to the presence of peptides. Apart from monosodium glutamate, most of the amino acids are present in the fractions at concentrations lower than their threshold values measured in water. Therefore, the hypothesis of synergistic effects among amino acids or between amino acids and other kinds of compounds, such as salts, can be raised. Moreover, the fractions containing free amino acids are also generally the most aromatic. The nature and the origin of these volatile compounds responsible for these aromas have to be determined.