Exploring accelerated oxidative and physicochemical properties of Arbequina and Moroccan Picholine olive oils: A preliminary study on molecular interactions

This preliminary study explores the oxidative and physicochemical properties of Arbequina and Moroccan picholine olive oils by subjecting these samples to accelerated oxidation at a temperature of 60 degrees C for 16 days, using Shaal's method. The results reveal significant variations in physicochemical characteristics between the two extra-virgin olive oil cultivars. Arbequina olive oil stands out for its high phenol content of 104.66 mg/kg, which gives this variety a better oxidative stability of 12.18 h. It also rich in alpha-tocopherol, with a concentration of 219.64 mg/kg. However, Moroccan Picholine oil was the first to surpass the set top limits, indicating lower stability. The results of volatile compound analysis by headspace solid-phase microextraction show that nonanal and 2-undecenal are the main volatile compounds present in all the oils examined. In addition, the dominant fatty acids in these samples are oleic acid, linoleic acid and palmitic acid. Other important observations include a decrease in chlorophyll and carotenoid levels in both cultivars, as well as a progressive decrease in IC50 for Arbequina oil over time from 66.62 mg/ml to 54.73 mg/ml, while picholine shows the opposite trend. In summary, the study establishes a clear link between the oxidative stability of olive oil and its polyphenol and tocopherol content. Arbequina oil, with its elevated phenol and alpha-tocopherol levels, demonstrates higher stability, contributing to a comprehensive understanding of factors influencing olive oil quality.