Identification of Specific Odour Markers in Oil from Diseased Olive Fruits Using an Electronic Nose

摘要

This study applied an electronic nose (e-nose) to identify specific odour markers in oil extracted from diseasedolive fruits. Virgin olive oil (VOO) is a valuable vegetable oil extracted from fresh and healthy olive fruits.Anthracnose, the most important fungal disease of olives worldwide, results in damage to mature olive fruits.The HERACLES II e-nose (Alpha MOS, Toulouse, France) is based on dual fast gas chromatographytechnology (two columns of different polarities in parallel coupled to two flame ionization detectors). Therefore,two chromatograms are obtained simultaneously, providing a fingerprint of the product to allow an easycomparison of the overall odour profiles of a batch with the target profile. E-nose analysis made it possible topre-screen specific odour compounds. Comparing the chromatograms showed important differences in theconcentrations of volatile compounds between VOO and the oil extracted from diseased fruits. Twelve peakswere highly specific for oil from the diseased fruits. To allow the e-nose to determine the minimum limit ofdetection of the unique odour compounds, olive oil from healthy fruit was mixed with oil from diseased fruits atdifferent concentrations. Alpha MOS’s AroChemBase library was used to investigate the nature of the uniqueodour compounds in the oils based on the retention times of the main peaks. Almost all of these compoundswere associated with off-odours of oil from diseased olive fruits. These results have shown that specific odourmarkers in oil extracted from diseased olive fruits can be identified using the e-nose.