EVALUATION OF THE KEY ODORANTS IN A THERMALLY TREATED SOLUTION OF RIBOSE AND CYSTEINE BY AROMA EXTRACT DILUTION TECHNIQUES

Application of the aroma extract dilution analysis on a solvent extrac t isolated from a thermally treated solution (145 degrees C; 20 min) o f cysteine/ribose led to the identification of 2-furfurylthiol, 3-merc apto-2-pentanone, 2-methyl-3-furanthiol, 5-acetyl-2,3-dihydro-1,4-thia zine, 3-mercapto-2-butanone, and bis(2-methyl-3-furyl) disulfide showi ng the highest flavor dilution factors among the 29 odor-active volati les. HRGC/olfactometry of decreasing headspace volumes established esp ecially 2-furfurylthiol and 2-methyl-3-furanthiol as important odorant s and revealed 2-thenyl mercaptan and ethyl mercaptan as further key c ontributors to the overall roasty, meatlike, sulfury odor of the model mixture. 5-Acetyl-2,3-dihydro-1,4-thiazine, identified for the first time among the volatiles of Maillard model reactions or foods, exhibit ed an intense roasty, popcorn-like odor at the low odor threshold of 0 .06 ng/L of air, which was of the same order of magnitude as those rep orted in the literature for the roasty-smelling odorants 2-acetyl-1-py rroline and 2-acetyl-2-thiazoline.