Skip to Content
MilliporeSigma
  • Identification of Key Off-Flavor Compounds in Thermally Treated Watermelon Juice via Gas Chromatography-Olfactometry-Mass Spectrometry, Aroma Recombination, and Omission Experiments.

Identification of Key Off-Flavor Compounds in Thermally Treated Watermelon Juice via Gas Chromatography-Olfactometry-Mass Spectrometry, Aroma Recombination, and Omission Experiments.

Foods (Basel, Switzerland) (2020-02-26)
Xiao Yang, Fan Yang, Ye Liu, Jian Li, Huan-Lu Song
ABSTRACT

Thermally treated watermelon juice (TW) presents a strong unpleasant smell, resulting in poor consumer acceptance. It is necessary to identify the key off-flavor compounds in TW. Solid-phase microextraction (SPME) and solvent-assisted flavor evaporation (SAFE) coupled with gas chromatography-olfactometry-mass spectrometry (GC-O-MS) were applied to the extraction and analysis of the volatile compounds in TW. Five aroma-active compounds and seven off-flavor compounds were quantitatively analyzed by the standard curve method. Based on the flavor dilution factor (FD), odor attribute, odor activity value (OAV) of volatile compounds, and partial least-squares regression (PLSR) analysis, seven key off-flavor compounds were preliminarily identified as follows: (E)-2-heptenal, decanal, octanol, diisopropyl disulfide, hexanol, (E)-2-decenal, and (E)-2-octenol. Aroma recombination proved that these off-flavor compounds above had a negative impact on the overall flavor in TW. Omission experiments were taken to confirm them further. Finally, octanol, diisopropyl disulfide, and (E)-2-decenal were identified as the most potent off-flavor compounds in TW.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
trans-2,cis-6-Nonadienal, 95%
Sigma-Aldrich
2-Methyl-3-heptanone, 99%
Sigma-Aldrich
trans-2,cis-6-Nonadien-1-ol, ≥95%, stabilized, FCC, FG
Sigma-Aldrich
Poly(dimethylsiloxane), viscosity 1.0 cSt (25 °C)
Sigma-Aldrich
trans-2-Nonenal, 97%
Sigma-Aldrich
trans-2-Heptenal, ≥95%
Sigma-Aldrich
trans-2-Octenal, ≥95%, stabilized, FG
Sigma-Aldrich
1-Hexanol, anhydrous, ≥99%
Sigma-Aldrich
Decanal, ≥98% (GC), liquid