Chemometric Characterization of Fruit Juices from Spanish Cultivars According to Their Phenolic Compound Contents: I. Citrus Fruits

Abstract

The data set composed by phenolic compound profiles of 83 <i>Citrus</i> juices (determined by HPLC-DAD-MS/MS) was evaluated by chemometrics to differentiate them according to <i>Citrus</i> species (sweet orange, tangerine, lemon, and grapefruit). Cluster analysis (CA) and principal component analysis (PCA) showed natural sample grouping among <i>Citrus</i> species and even the <i>Citrus</i> subclass. Most of the information contained in the full data set can be captured if only 15 phenolic compounds (concentration ≥10 mg/L), which can be quantified with fast and accurate methods in real samples, are introduced in the models; a good classification which allows the confirmation of the authenticity of juices is achieved by linear discriminant analysis. Using this reduced data set, fast and routine methods have been developed for predicting the percentage of grapefruit in adulterated sweet orange juices using principal component regression (PCR) and partial least-squares regression (PLS). The PLS model has provided suitable estimation errors