Characterization of rare virgin olive oils cultivated in southern Tunisia during fruits development process: major compounds and oxidative state in tandem with chemometrics
The present study reports the olive oil quality properties, namely free fatty acid, peroxides index, purity properties [fatty acid and triacylglycerol (TAG) composition], antioxidant compounds (total phenol, carotenoid and chlorophyll content) and oxidative stability. These analyses were performed for three rare cultivars grown in southern Tunisia (region of Tataouine). All the samples have presented good quality according to the international olive council norms. Nevertheless, there was a difference in many of the evaluated parameters as a function of ripening stages and cultivars. The oleic acid and linoleic acid amounts of olive oils increased with the ripening progress, with the highest rates were found in Fakhari cultivar. The most abundant triacylglycerols of olive oils were OOO, POO, LOO + PLnP, PLO + SLL and POP. Moreover, a general decrease (p < 0.05) of the total phenolic content, pigments content and oxidative stability were observed during maturation. The principal component analysis was used to classify nine olive oils samples depending on cultivars and maturity degree.
KeywordsTriacylglycerols Oxidative stability Phenolic content Rare cultivars Principal component analysis
The authors acknowledge the help of Pr. Jacques Artaud for the TAG analysis. The authors acknowledge also National Funds through Ministry of Higher Education-Tunisia for financing MedOOmics Project “Mediterranean Extra Virgin Olive Oil Omics: profiling and fingerprinting”—“Arimnet2/0001/2015”. The authors also extend thanks to Leila Mahfoudhi, Major teacher of English in the Sfax Faculty of Sciences, for having proofread and polished the language of the manuscript.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
Compliance with ethics requirements
This article does not contain any studies with human or animal subjects.
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