Olive pomace oil shows a much better performance in discontinuous (domestic) and continuous (industrial) frying than conventional sunflower oils and similar oils, or even slightly better than high oleic sunflower oils. This is one of the main conclusions drawn from the comparative research carried out by the Institute of Science and Technology of Food and Nutrition (ICTAN) of the Higher Council for Scientific Research (CSIC).
The study “Behavior of Olive Pomace Oil in frying and comparison with conventional sunflower and high oleic sunflower oils” has been presented by its principal investigator, Gloria Márquez, at the ‘The Science of Croquettes‘ event organized by the Interprofessional of the Olive Pomace Oil (Oriva).
According to the researcher Gloria Márquez, three batches were used for each category of oil (from different periods of the campaign in the case of olive-pomace oil). Their behavior was evaluated in equal conditions using potatoes as cooked food in the discontinuous and continuous frying modes. In this way, the results have been analyzed from a double angle: the quality and modifications in the oils and in the product used.
According to the results obtained, the best frying behavior with respect to conventional sunflower oils is due to differences in oleic acid content. In relation to high oleic sunflower oils, the additional advantage of olive-pomace oil is the protective and joint action of the minority compounds, highlighting the positive effect attributed to squalene and beta-sitosterol.
In terms of durability, the tests also showed a high stability of olive-pomace oil. The comparative study in discontinuous frying showed that, in the oils tested and the established conditions, the conventional sunflower oils reached their maximum use level, set by regulations in 25% of polar compounds, in the 9th-10th fry and the of high oleic sunflower in the 17th-18th fry. Meanwhile, two of the lots of olive-pomace oil have reached the 21st fry. ‘This good stability has also been observed over 40 fritters in the continuous frying trials,’ commented the ICTAN researcher.
In relation to the health properties of olive-pomace oil, during the investigation it was confirmed that ‘considerable quantities of bioactive compounds are maintained during frying, especially of triterpene alcohols and aliphatic alcohols’. The biological results obtained so far on the latter suggest that they can exert a protective function against the inflammatory damage inherent to any pathological process. As for squalene and beta-sitosterol, they stand out for their antioxidant properties.