18C-33 |
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T. A. Gnadt1, L. JASSO1, and K. R. Cadwallader. (1) Dept. Food Science and Human Nutrition, Univ. of Illinois at Urbana-Champaign, 1302 W. Pennsylvania Ave, Urbana, IL 61801 Chipotle peppers are dried, smoked jalapeno (Capsicum annuumvar. annuum) peppers. Originally from Mexico, chipotle peppers have gained popularity in Latin-American cuisine, but only limited information is available on their characteristic aroma components. Our previous studies of chipotle peppers revealed the contribution of several semi-volatile compounds to chipotle aroma, but it was evident by those results that some highly volatile compounds may also play important roles in chipotle aroma. The objective of this study was to compare two different methods, direct solvent extraction-solvent-assisted flavor extraction (DSE-SAFE) and dynamic headspace sampling (DHS), for the analysis of the aroma components of chipotle peppers. Three commercial samples of Mexican origin were obtained from specialty retailers. For DSE-SAFE, ground, stem-free samples were rehydrated with deodorized water and then extracted three times with diethyl ether followed by a SAFE cleanup step. Aroma extracts were analyzed by gas chromatography-olfactometry (GCO) and GC-mass spectrometry (GC-MS) using cool on-column injection. DHS was performed on rehydrated chipotle peppers by purging (N2) volatiles onto a Tenax trap. Trapped volatiles were thermally desorbed and cryofocused prior to analysis by GCO and GC-MS. Predominant semi-volatile aroma compounds identified by DSE-SAFE included 2-isobutyl-3-methoxyphenol, linalool, guaiacol, syringol, 4-hydroxy-2,5-dimethyl-3(2H)-furanone and 3-hydroxy-4,5-dimethyl-3(5H)-furanone. Meanwhile, DHS results indicated the importance of some highly volatile compounds, including methylpropanal, 2,3-butanedione, and 2- and 3-methylbutanal. The aroma of chipotle pepper is highly complex, consisting of both highly volatile and semivolatile compounds. This study demonstrates the necessity of using complementary volatile isolation techniques so that highly volatile and semi-volatile components are evaluated.
Session 18C, Food Chemistry: Food composition, analysis and volatiles
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |