Tunisian Table Olive Oil Traceability and Quality Using SNP Genotyping and Bioinformatics Tools

Abstract

To enhance and highlight the authentication and traceability of table olive oil, we considered the analysis of 11 Tunisian table olive cultivars based on seven SNP molecular markers (SOD, CALC, FAD2.1, FAD2.3, PAL70, ANTHO3, and SAD.1) localized in six different genes. Accordingly, we assessed the potential genotype-phenotypes links between the seven SNPs, on the one hand, and the quantitative and qualitative parameters, on the other. The obtained genotypes were analyzed with computational biology tools based on bivariate analysis, multinomial logistic regression, and the Bayesian networks modeling. Obtained results showed that PAL70 SNP marker was negatively influenced by the phenol rate (r = -0.886; p <0.001), the oxidative stability (r = -0.884; p <0.001), traducing a direct effect of the PAL70 genotype deviations on the proportion of total phenol for each variety. Additionally, we revealed a significant association of SAD.1 marker with the content of the linolenic unsaturated fatty acids (C18:3; p=0.046). Moreover, SAD.1 was positively correlated with the saturated stearic acid C18:0 (r = 0.644; p = 0.032) based on multinomial logistic regression and Bayesian networks modeling, respectively. This research work provides better understanding and characterization of the quality of Tunisian table olive and supplies a significant knowledge and data information for table olive traceability and breeding.

Eleven Monovarietal Extra Virgin Olive Oils from Olives Grown and Processed under the Same Conditions: Effect of the Cultivar on the Chemical Composition and Sensory Traits

“…On the whole, our findings corroborated the hypothesis that the oil fatty acid profile is strongly under genetic control. Ben Ayed et al [ 41 ] noticed that oleic acid amounts in olive oil can be strongly related to the polymorphisms of fatty acid-related genes, such as the stearoyl-acyl carrier protein desaturase gene (SAD). TT-SAD.1 genotype was found to be associated with a higher proportion of monounsaturated fatty acids, mainly oleic acid, as well as with lower proportions of palmitic acid, thus causing olive varieties with this genotype to produce more monounsaturated fatty acids, namely oleic acid, than saturated fatty acids.…”

Molecular Approaches to Agri-Food Traceability and Authentication: An Updated Review

“…These panels are available in different species of agri-food interest such as grapevine, olive, pulses, cacao, and coffee [ 76 , 77 , 78 , 79 , 80 ]. Most of the works using a SNP-based traceability approach have focused on olive oil analysis [ 40 , 41 ], however, SNPs have been efficiently employed in differentiating Arabica and Robusta coffee varieties [ 81 ], in the authentication of Portuguese wine [ 42 ], and in the identification of Nebbiolo variety in musts and wines [ 43 ].…”

How to Choose a Good Marker to Analyze the Olive Germplasm (Olea europaea L.) and Derived Products

“…SNP markers proved to be an excellent tool also for table olive and oil authenticity testing, being used in all the Mediterranean countries where these products have a substantial economic value [162].…”