Strategy for the identification of key odorants: application to shrimp aroma.
The GC-SNIF technique was used to obtain the olfactograms of shrimps, and their impact odorants were identified by MS hyphenated to the GC/olfactometric system and by comprehensive two-dimensional GC hyphenated to a time-of-flight MS. Confirming these identifications by their linear retention indices required application of a new strategy to compare retention indices between both instruments and with the in-house database. The aldehydes were confirmed by using their pentafluorophenylhydrazone derivatives, and 2-ethyl-3,5-dimethyl pyrazine had to be resolved from co-eluting compounds and then identified by multidimensional GC hyphenated to an MS and a sniff port. In both shrimp products, the most important odorants were trimethylamine, 2-acetyl-1-pyrroline, and 2-ethyl-3,5-dimethyl pyrazine, together with common carbonyl compounds.
Rochat
S
S
Firmenich SA, Corporate R&D Division, P.O. Box 239, CH-1211 Geneva 8, Switzerland.
Egger
J
J
Chaintreau
A
A
D053000:Analytic Sample Preparation Methods; D000818:Animals; D001267:Atlantic Ocean; D016208:Databases, Factual; D008401:Gas Chromatography-Mass Spectrometry / Q000295:instrumentation / Q000379:methods*; D006257:Head; D006801:Humans; D006834:Hydrazines; D007202:Indicators and Reagents; D008744:Methylamines / Q000032:analysis; D015394:Molecular Structure; D009812:Odorants / Q000032:analysis*; D033542:Pandalidae / Q000737:chemistry*; D011108:Polymers; D011719:Pyrazines / Q000032:analysis; D011758:Pyrroles / Q000032:analysis; D012758:Shellfish / Q000032:analysis*; D012984:Software; D014835:Volatilization; D005464:Fluorobenzenes; D005466:Fluorocarbons
D006834:Hydrazines; D007202:Indicators and Reagents; D008744:Methylamines; D011108:Polymers; D011719:Pyrazines; D011758:Pyrroles; C010514:tenax; C031120:(pentafluorophenyl)hydrazine; D005464:Fluorobenzenes; D005466:Fluorocarbons; C426303:2-acetyl-1-pyrroline; C023336:trimethylamine; C522035:2-ethyl-3,5-dimethylpyrazine