Chemical Profiles of Twenty-three Monovarietal Olive Oils Produced in Liangshan Region of China.

The main objective of this study was to differentiate twenty-three monovarietal olive oils produced in China (Azappa, Thiaki, Leucocarpa ovoid, manzanillo de labata, etc.) by studying their physicochemical properties, fatty acid profiles and oxidative stability. The majority of analytical indicators had statistically significant differences (p < 0.05). The tested cultivars produced excellent olive oils with an appreciable amount of natural antioxidants and chemical composition within the legal range. Our results demonstrate that Leucocarpa ovoid oil was characterized by high mean levels of total phenols (401.8 mg/kg), oleic acid (79.62%) and oxidative stability (18.64 h). Additionally, five types of olive oil were selected due to their high overall quality. Investigation of virgin olive oils indicates that the differences in the fatty acid profiles, phenols, sterols and tocopherols may be caused by genetic factors. The principal components analysis (PCA) results showed a strong differentiation between various cultivars in regard to their fatty acid composition and phenol, sterol and tocopherol levels. These components can be effective tools for efficient comparison and differentiation of these cultivars. To the best of our knowledge, this is the first work on the differentiation of the chemical constituents of virgin olive oils.