Olive Oil Quality of Cultivars Cultivated in Super-High-Density Orchard under Cold Weather Conditions

In this work, the quality parameters of the oils of seven different varieties of olives (Olea europaea cvs, Arbequina, Arbosana, Cobrancosa, Cornicabra, Koroneiki, Cacerena, and Chiquitita) grown in hedgerow under cold conditions during three consecutive seasons were analyzed in order to evaluate their adaptation to this growing system. For this purpose, virgin olive oils (VOOs) were extracted, and, in addition to evaluating the indices of hydrolytic, oxidative, and sensory deterioration of the oils, their content in photosynthetic pigments and their composition in fatty acids and phenolic compounds were determined. The correlation between oxidative stability and the parameters evaluated has been studied, with the highest correlation coefficients found for the ratio MUFA/PUFA (0.871) and the content of secoiridoid phenolic compounds (0.816). Furthermore, principal component analysis was performed with the phenolic composition data from each season, which demonstrated the major influence of genetic factors in the phenolic composition of VOO. None of the VOOs presented hydrolytic, oxidative, or sensory deterioration, so all of them remained in the extra category. However, it should be noted that the mean ultraviolet absorbance values were significantly higher in Cornicabra and significantly lower in Cacerena oils. In spite of this, the oxidative stability was significantly higher in Cornicabra oils (125 h), which also had the highest mean phenolic content (1035 mg kg(-1) oil), while the lowest phenolic content values were found in Arbequina and Chiquitita (58 and 52 h, respectively).

Automated summary

This study analyzed the quality parameters of oils from seven different varieties of olives grown in hedgerow under cold conditions. The oils were evaluated for hydrolytic, oxidative, and sensory deterioration, as well as their content in photosynthetic pigments, fatty acids, and phenolic compounds. The study found a strong correlation between oxidative stability and the ratio of MUFA/PUFA and the content of secoiridoid phenolic compounds. Genetic factors were found to have a major influence on the phenolic composition of the oils. All of the oils remained in the extra category, although there were significant differences in UV absorbance and phenolic content among the varieties.