FLAVOR CONSTITUENTS OF AQUEOUS FRACTION EXTRACTED FROM COMTE CHEESE BY LIQUID CARBON-DIOXIDE

Isolation, purification and identification of some low-molecular-weigh t compounds from a water-soluble extract of Comte cheese was achieved. We used liquid CO2 extraction, subsequent fractionation (by gel perme ation and reserve-phase HPLC) and mass spectometry. Major constituents were N-acyl amino acids (N-acetyl methionine, N-propionyl methionine, N-propionyl leucine, N-propionyl phenylalanine), dike-topiperazines ( cyclo(Pro-Pro), cyclo(Pro-Val), cyclo(Pro-Phe), cyclo(Pro-Leu), cyclo( Pro-Ala)) and non-peptide compounds (theobromine, 4-methyl-t-thiazolee thanol, uracil, (5-6)dihydro-uracil, thymine). These compounds were sy nthesized and tasted. Most were bitter. N-propionyl methionine had a c heese flavor but was not detected when added to a simulated cheese at 180 mg/L.