Monitoring the Profile of Volatile Compounds During the Storage of Extra Virgin Olive Oils Produced in Brazil from the Koroneiki Variety Using the HS-SPME Technique

This work aimed to evaluate changes in the profile of volatile compounds of extra virgin olive oils (EVOOs) from the states of Minas Gerais and Rio Grande do Sul (Brazil) during 8 months of storage. The samples of Koroneiki olive oils were characterized for fatty acid composition, acidity, peroxide value, and ultraviolet absorbance. Volatile compounds were identified and estimated by headspace solid-phase microextraction (HS-SPME), gas chromatography coupled to mass spectrometry (GC-MS), and flame ionization detection (GC-FID). The results obtained for fatty acid composition, free fatty acids, peroxide value, and ultraviolet absorbance are characteristic of extra virgin olive oils. The main volatile compounds identified at zero storage time were hexanal, (E)-2-hexenal, (Z)-3-hexenol, (Z)-3-hexenyl acetate, and hexyl acetate, all from the lipoxygenase pathway (LOX) and responsible for the characteristic green odor of EVOOs. The major compound found was (E)-2-hexenal, which also had the greatest decrease during storage. In the same period, (E)-2-heptenal, octanal, nonanal, and (E)-2-decenal, compounds associated to undesirable sensory characteristics in olive oils, were identified mainly in the eighth month of storage. Through PCA and fatty acid composition, the samples could be grouped according to their geographic origin.

Automated summary

This study aimed to evaluate the changes in volatile compounds of extra virgin olive oil (EVOOs) from the states of Minas Gerais and Rio Grande do Sul (Brazil) during 8 months of storage. The results showed that the fatty acid composition, acidity, peroxide value, and ultraviolet absorbance of the oils were characteristic of EVOOs. The main volatile compounds identified at the beginning of storage were from the lipoxygenase pathway (LOX) and responsible for the characteristic green odor of EVOOs. Undesirable compounds were detected mainly in the eighth month of storage.