Classification of Greek Olive Oils from Different Regions by Machine Learning-Aided Laser-Induced Breakdown Spectroscopy and Absorption Spectroscopy

Nikolaos Gyftokostas; Eleni Nanou; Dimitrios Stefas; Vasileios Kokkinos; Christos Bouras; Stelios Couris

doi:10.3390/molecules26051241

Classification of Greek Olive Oils from Different Regions by Machine Learning-Aided Laser-Induced Breakdown Spectroscopy and Absorption Spectroscopy

Molecules. 2021 Feb 25;26(5):1241. doi: 10.3390/molecules26051241.

Authors

Nikolaos Gyftokostas^{1

2}, Eleni Nanou^{1

2}, Dimitrios Stefas^{1

2}, Vasileios Kokkinos³, Christos Bouras³, Stelios Couris^{1

2}

Affiliations

¹ Department of Physics, University of Patras, 26504 Patras, Greece.
² Institute of Chemical Engineering Sciences (ICE-HT), Foundation for Research and Technology-Hellas (FORTH), 26504 Patras, Greece.
³ Department of Computer Engineering & Informatics, University of Patras, 26504 Patras, Greece.

Abstract

In the present work, the emission and the absorption spectra of numerous Greek olive oil samples and mixtures of them, obtained by two spectroscopic techniques, namely Laser-Induced Breakdown Spectroscopy (LIBS) and Absorption Spectroscopy, and aided by machine learning algorithms, were employed for the discrimination/classification of olive oils regarding their geographical origin. Both emission and absorption spectra were initially preprocessed by means of Principal Component Analysis (PCA) and were subsequently used for the construction of predictive models, employing Linear Discriminant Analysis (LDA) and Support Vector Machines (SVM). All data analysis methodologies were validated by both "k-fold" cross-validation and external validation methods. In all cases, very high classification accuracies were found, up to 100%. The present results demonstrate the advantages of machine learning implementation for improving the capabilities of these spectroscopic techniques as tools for efficient olive oil quality monitoring and control.

Keywords: LDA; LIBS; PCA; SVC; classification; laser-induced breakdown spectroscopy; machine learning; olive oil; visible absorption.

MeSH terms

Discriminant Analysis
Greece
Linear Models
Machine Learning*
Olive Oil / analysis*
Principal Component Analysis*
Spectrophotometry, Atomic
Spectrophotometry, Ultraviolet
Spectroscopy, Near-Infrared

Substances

Olive Oil