Related Experiment Video
Updated: May 14, 2026

Identification of Fatty Acids in Bacillus cereus
Published on: December 5, 2016
Shared retronasal identifications of vapor-phase 18-carbon fatty acids
Tariq Chukir1, Richard B Darlington, Bruce P Halpern
1Weill Cornell Medical College, College of Medicine, Doha, Qatar.
Abstract:
The long-chain 18-carbon fatty acids linoleic, oleic, and stearic acids, retronasally in vapor phase, are discriminated from blanks and each other. However, ability to linguistically identify them was unknown. To explore this, a Focus Group and then Check-All-That-Apply measures gave 9 identifiers for the 3 fatty acids plus phenylethyl alcohol (PEA) and geraniol. Next, participants selected 1 of the 9 identifiers from a computer-based display. It was found that the modal identification for linoleic acid was 23% "Rubbery" (next 18% "Oily" and "New Plastic"), oleic acid was 21% Oily (next 19% Rubbery), and stearic acid was 43% Rubbery (next 22% New Plastic), but linoleic acid received ~40% food-related identifiers. Geraniol was 96% "Lemon," and PEA was 67% "Flowers." Identifications for fatty acids differed significantly (P ≤ 0.05) from those for geraniol for most participants (86%) and from those for PEA for 59% of participants. Stearic acid identifications differed significantly from those for linoleic and oleic acids for 32% of participants. However, identification for linoleic acid differed significantly from those for oleic acid for only 14% of participants. Overall, retronasal vapor-phase stearic acid was identified differently from other 18-carbon fatty acids by a substantial minority of participants, but linoleic and oleic acids were not, suggesting that these 2 vapor-phase 18-carbon fatty acids can be identified retronasally as a group but not separately.
More Related Videos
08:43PTR-ToF-MS Coupled with an Automated Sampling System and Tailored Data Analysis for Food Studies: Bioprocess Monitoring, Screening and Nose-space Analysis
Published on: May 11, 2017
11:14Fatty Acid 13C Isotopologue Profiling Provides Insight into Trophic Carbon Transfer and Lipid Metabolism of Invertebrate Consumers
Published on: April 17, 2018
Related Concept Videos
NMR and Mass Spectroscopy of Carboxylic Acids
While α protons of carboxylic acids absorb at 2–2.5 ppm, β protons absorb further upfield.
Carboxylic acids are easily identified by dissolving them in deuterium oxide, which results in a rapid exchange of the acidic protons with deuterium. This leads to the disappearance of the acidic...
Spectroscopy of Carboxylic Acid Derivatives
In the...
IR Frequency Region: Fingerprint Region
The...
IR and UV–Vis Spectroscopy of Carboxylic Acids
However, the stretching absorptions for the C=O bond vary depending on the structure of carboxylic acids. The C=O bond of the free carboxylic acids shows a higher stretching frequency, 1760 cm−1, while H-bonded carboxylic acids (dimers) exhibit stretching absorptions at a lower frequency, 1710 cm−1. The C=O bond of the...
Mass Spectrometry: Long-Chain Alkane Fragmentation
NMR Spectroscopy and Mass Spectrometry of Aldehydes and Ketones