Physicochemical traits of olive oil (‘Moroccan Picholine’ cultivar) produced using three extraction technologies in Tetouan province (northern Morocco). A comparative study with refined soybean and sunflower oil

Abstract

Morocco is a potential producer of olive oil (OO), which comes mainly from ‘Moroccan Picholine’ cultivar grown under contrasting environments. Little is devoted to characterization of ‘Moroccan Picholine’ OO (MPOO) from central-northern Morocco as a potential productive region. Hence the originality of this paper, which aimed at investigating MPOO from Tetouan province (sub-humid Mediterranean climate). MPOO was sampled from three extraction processes namely 2-phase (2P), 3-phase (3P), and super-pressure (SP) and compared with commonly consumed table oils (TOs) including soybean SBO and sunflower SFO. MPOO produced using 2P and SP meet the criteria for extra-virgin OO, while those obtained from 3P are classified as ordinary OO. In fact, OO extracted using 3P exhibited high levels of acid value (AV), UV extinction coefficient K270, pigments, monounsaturated fatty acids, stigmasterol, and β-sitosterol, whereas, OO sourced from 2P displayed high peroxide value (PV), UV extinction coefficient K232, saturated, and polyunsaturated fatty acids, cholesterol, campesterol, and ∆7-stigmasterol. OOs had elevated levels of AV, PV, and pigments compared to TOs, which exhibited increased levels of K232, K270, and sterols. Principal component analysis and cluster analysis clearly separated OOs from TOs. Based on simple regressions, several mathematical models were developed to describe the relationship among the studied physicochemical traits. To conclude, OO from 2P displayed the best quality indices compared to those from SP and 3P systems. The obtained results provide valuable information for producers, industrialists, and consumers and promote the value of Moroccan olive oil on the international market.