Abstract
<jats:p>The behavior of Uruguayan virgin olive oil during the frying of frozen, pre-fried potatoes was evaluated. The frying cycles consisted of 1 hour of thermo-oxidation of the oil, followed by frying 300 g of potatoes. Samples were taken every five cycles, replacing the oil consumed (sampling + oil absorption). The following deterioration parameters were monitored: polar compounds (PC), total polymers (TP), peroxide value (PV), extinction coefficient at 268 nm (K268), and free acidity (%A), as well as the evolution of the fatty acid profile and the content of natural antioxidants (tocopherols and polyphenols). An increase in PC, TP, and K268 was observed as the frying cycles progressed. In contrast, PV and %A showed a reduction compared to the original oil and subsequently a slight upward trend, which was not significant in PV. A marked loss of both types of natural antioxidants was observed during the early stages of the study. This was accompanied by a significant reduction in the ratio of polyunsaturated fatty acids to palmitic acid. In conclusion, although this oil performed well and remained stable during the frying process, its main advantages, such as natural antioxidants with known bioactive properties, were lost during the first frying cycles.</jats:p>