Development of rancidity in wheat germ analyzed by headspace gas chromatography and sensory analysis

J Agric Food Chem. 2000 Aug;48(8):3522-7. doi: 10.1021/jf981309t.


Wheat germ is susceptible to oxidation due to its high content of unsaturated oil. Volatile compounds in stored wheat germ were evaluated using dynamic headspace gas chromatography (HS-GC) and sensory analysis. Preliminary comparisons were also made between freshly prepared wheat germ and wheat germ subjected to microwave heating at 45 and 55 degrees C prior to storage at room temperature. The progress of oxidation was followed in untreated wheat germ for 4 weeks and in heat-treated wheat germ for 7 weeks by HS-GC and sensory evaluation. Significant (p < 0.05) changes in rancid odor and flavor were observed in the untreated wheat germ after 3 weeks, whereas no corresponding difference was observed in the microwave-heated wheat germ after 7 weeks of storage. Identification of a total of 36 volatile compounds was performed according to their mass spectra and Kovats indices. The major volatiles were hexanal, alpha-pinene, 1-hexanol, and 3-carene. In addition to analysis of a short period of storage, 30 volatile compounds were identified from the headspace of wheat germ stored for >1 year.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromatography, Gas / methods*
  • Female
  • Humans
  • Male
  • Odorants*
  • Triticum / chemistry*