Discrimination and characterisation of extra virgin olive oils from three cultivars in different maturation stages using Fourier transform infrared spectroscopy in tandem with chemometrics

Abstract

A methodology based on Fourier transform infrared (FTIR) spectroscopy, combined with multivariate analysis methods, was applied in order to monitor extra virgin olive oils produced from three distinct cultivars on different maturation stages. For the first time, this kind of methodology is used for the simultaneous discrimination of the maturation stage, and different cultivars. Principal component analysis and discriminant analysis were utilised to create a model for the discrimination of olive oil samples. Partial least squares regression was employed to design calibration models for the determination of chemical parameters. The performance of these models was based on the multiple coefficient of determination (R(2)), the root mean square error of calibration (RMSEC) and root mean square error of cross validation (RMSECV). The prediction models for the chemical parameters resulted in a R(2) ranged from 0.93 to 0.99, a RMSEC ranged from 1% to 4% and a RMSECV from 2% to 5%. It has been shown that this kind of approach allows to distinguish the different cultivars, and to clearly discern the different maturation stages, in each one of these distinct cultivars. Furthermore, the results demonstrated that FTIR spectroscopy in tandem with chemometric techniques allows the creation of viable and accurate models, suitable for correlating the data collected by FTIR spectroscopy, with the chemical composition of the EVOOs, obtained by standard methods.

FTIR chemometrical approach for clonal assessment: Selection of Olea europaea L. optimal phenotypes from cv. Cobrançosa

“…In fact, several research works have shown the efficiency of this technique for distinct determinations in olive oils, such as geographical origin or cultivars used, besides the detection of possible adulterations . Furthermore, in recent years the joint application of FTIR analysis and multivariate determinations has emerged as an interesting approach that allows the determination of several chemical parameters of olive oil, such as fatty acids, peroxide values, acidity, phenolic and volatile compounds, freshness, and oxidized fatty acids …”

FTIR–ATR spectroscopy applied to quality control of grape-derived spirits

“…In addition, it has recently been used in the control of honeys' sugar concentration (Anjos, Campos, Ruiz, & Antunes, 2015) and in olive oil characterisation (Gouvinhas, de Almeida, Carvalho, Machado, & Barros, 2015). Despite the increasing interest and the recent developments, few studies focus on the use of FTIR-ATR for the quality control of grape-derived distillates (grape marc spirits, wine spirits and brandies).…”

Principal Component Analysis Application on Flavonoids Characterization

“…Despite some studies performed on the identification of compound using few combination of chemometric techniques such as hierarchical cluster analysis [24], PCA, partial least square (PLS) and factor discriminant analysis (FDA) [25], the application of PCA into the characterization model has not been undertaken yet.…”