2.7 Coffee and tea

Differentiation of coffee samples is based mostly on fatty acid profiles and volatile and semi-volatile compounds (organic acids, sugars, terpenoids). Differentiations of various tea plants were based exclusively on volatile components. In order to enable differentiations and classifications of investigated samples of beverages, the data obtained after GC analysis were combined with various chemometric techniques: HCA, PCA, SLDA and OPLS-DA. Table 7 represents chronological literature data on the authentication and adulteration detection procedures of coffee and tea from various plant species.

chiral GC GC enantioselective comprehensive two-dimensional gas

chromatography

MCOCPLS Monte Carlo one-class partial least squares

P-IRMS pyrolysis isotope ratio mass spectrometry

SIMCA soft independent modeling of class analogy SLDA stepwise linear discriminant analysis

OPLS-DA orthogonal projections to latent structures discriminant

Q-TOF-MS quadrupole accurate mass time-of-flight mass spectrometry

OC-SVM one-class support vector machine

analysis

PCA principal component analysis PCoA principal coordinate analysis PLS principal least squares regression

QDA quadratic discriminant analysis R-SVM recursive support vector machine RDA regularized discriminant analysis

SPME solid-phase microextraction SVM support vector machine

Kristian Pastor\*, Marijana Ačanski and Djura Vujić

\*Address all correspondence to: pastor@tf.uns.ac.rs

provided the original work is properly cited.

Faculty of Technology Novi Sad, University of Novi Sad, Novi Sad, Serbia

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

HCA hierarchical cluster analysis

HR high resolution HS headspace HT high temperature IR isotope ratio IT ion-trap

Gas Chromatography in Food Authentication DOI: http://dx.doi.org/10.5772/intechopen.88512

kNN k-nearest neighbors KNN Kohonen neural network LC liquid chromatography LDA linear discriminant analysis MLP multilayer perceptron

MS mass spectrometry O olfactometry

RF random forests

TOF time-of-flight UF ultrafast module

Author details

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