Degradation of olive oil by light or heating. Comparative electronic nose and sensory analysis data.

BABY, ROSA; CALVIÑO, A.M.; MESSINA, V.; CABEZAS, M.; BAUZA, M.; WALSOE DE RECA, N.E.

Journal Argentine Chemical Society

Asociación Química Argentina

Lugar: Buenos Aires; Año: 2005 vol. 93 p. 57 - 67

The aim of this work was to compare results of the SA and NE analysis of the odors of edible oils: soybean oil, sunflower oil, olive oil (before called ordinary olive oil) and virgin olive oil, and the different oxidation processes of olive oil and virgin olive oil under day light or heat.Sensorial panel discrimination of soybean and sunflower oils comparatively with extra-virgin olive oil or olive oil was successful. On the other hand, it could not successfully separate between them both, extra-virgin and olive oil. In comparison the e-nose could clearly discriminate the four studied oils: soybean oil, sunflower oil, extra-virgin olive oil and olive oilSensorial panel was not successful to separate both olive oil types. On the opposite, the electronic nose could clearly discriminate extra-virgin olive oil from olive oil.Non-degraded and degraded by day light specimen of  both types of  olive oils as analyzed by sensorial panel showed opposite results, i.e. a higher number of mistakes comparatively to hits for extra-virgin olive oil but, a higher number of hits in comparison with mistakes for the olive oil. Discrimination with the e-nose has shown that olive oil degradation by light seemed to be stronger for olive oil than for the extra-virgin type. This fact enables to infer that odorous products from the most degraded by light olive oil could be more easily smelled by the panel,Non-degraded and degraded by heat specimen of both types of olive oils as analyzed by the sensorial panel have shown  successful results in both cases since the number of hits is higher than that for mistakes. Otherwise, the number of hits and mistakes for both types of oils are very similar, indicating that the emission of odors from degradation products were able to be smelled similarly by panel. The e-nose results have shown a similar separation of non-degraded and degraded by heat specimen data pointing out a similar oxidation process by heat in both types of olive oils.