Improvement of Chemlali olive oil oxidative stability by blending with Chétoui and Rekhami cultivars

In order to improve the quality of Chemlali olive oil, characterised by a very low stability (2.09 h), blending with two different monovarietal oils in various proportions: Chétoui and Rekhami (known by their higher stability 7.79 and 13.99 h, respectively) was carried out. Results showed that blended oils had an improved oil composition compared to that of Chemlali. In fact, the highest percentage of Chétoui and Rekhami olive oils (90% of blending) can reduce the acidity up to 68.79% and 79.61%, respectively. At 50% blending, oleic acid increased from 53% to 59.54%, while palmitic acid decreased from 20.97% to 14.89% with Chétoui olive oil. At the lowest percentage (10-20%), chlorophylls in Chemlali olive oil underwent significant increase (from 0.18 to 0.47 and 0.65 mg kg⁻¹, respectively). The amount of carotenoids was higher when Chemlali was blended by 20-40% with Chétoui olive oil (from 2.23 to 4.13 and 4.33 mg kg⁻¹). Blending can be used in industrial applications to provide oils with improved composition related to stability, nutrition and functionality and endowed with the characteristics requested by consumers' preferences.