Putative Markers of Adulteration of Higher-Grade Olive Oil with Less Expensive Pomace Olive Oil Identified by Gas Chromatography Combined with Chemometrics

• Published in: Journal of agricultural and food chemistry 2017-07, Vol.65 (26), p.5375-5383
• Main Authors: Jabeur, Hazem, Drira, Malika, Rebai, Ahmed, Bouaziz, Mohamed
• Format: Article
• Language: English
• Subjects: Chromatography, Gas - methods; Discriminant Analysis; Food Contamination - analysis; Food Contamination - economics; Olive Oil - chemistry; Olive Oil - economics; Waste Products - analysis
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/acs.jafc.7b00687

This work has been performed to ascertain that extra-virgin olive oil (EVOO) is free of adulteration. For this purpose, refined pomace olive oils (RPOOs) are commonly used for extra-virgin olive oil adulteration and repassed olive oils (ROOs) are used for lampante olive oil (LOO) fraudulent operation. Indeed, fatty acid ethyl esters could be used as a parameter for the detection of EVOO fraud with 2% RPOO. The addition of >10% RPOO to EVOO would be detected by the amount of erythrodiol, uvaol, waxes, and aliphatic alcohols. Moreover, the use of stigmasta-3,5-diene content proved to be effective in EVOO adulteration even at a low level (with 1% RPOO). For the detection of adulteration of LOO with >5% ROO, the sum of erythrodiol, uvaol, and the waxes and esters can be considered as good markers of purity. Using linear discriminant analysis can identify the most discriminant variable that allows a faster and cheaper evaluation of extra-virgin olive oil adulteration by measuring only these variables.