Object: The oils from three monovarietals (Arbosana, Coratina, and Koroneiki) olive tree of different ages, which were planted in Xichang, Sichuan Province, one of the primary suitable areas for Olea europaea L. in China were analyzed.
Methods Used: Determination of physicochemical quality indices (FA, PV, K232, K270, and ΔK) was performed by using the analytical methodologies described in International Organization for Standardization (ISO) methods ISO 660, ISO 3960 and ISO 3960, respectively. Fatty acid profiles were analyzed by gas chromatography (GC) as FAMEs obtained by trans-esterification using potassium hydroxide in methanol (IOC, 2015). Minor compounds including tocopherols, phenolic compounds, total sterols, and squalene were determined by HPLC or GC-MS. Oxidative stability of olive oil was expressed as the induction time (h) in a 892 Professional Rancimat.
Results: The physicochemical quality indices (FA, PV, K232, K270, and ΔK) of the oils were within the prescribed limits established for extra virgin olive oil by IOC. Both cultivar and tree age affect the chemical composition of olive oils. The oils from the tree in mature period (7-year-old) demonstrated greater oxidative stability than the oils from younger (2-year-old) or older (11-year-old) trees mainly due to they contained more oleic acid and minor components.
Conclusions: The result showed that the quality of oils from 7-year-old trees was better than those from younger or older trees. However, the available research results indicated that the oils from ancient olive trees appeared superior quality if the tree were managed well. Thus, the level of olive cultivation in China needs further development.
