Multi-chemical analysis combined with chemometrics to characterize PDO and PGI Italian apples

J Sci Food Agric. 2021 Sep;101(12):5106-5115. doi: 10.1002/jsfa.11156. Epub 2021 Mar 4.

Abstract

Background: The use of PDO (protected designation of origin) and PGI (protected geographical indication) labels allows to protect and promote agricultural products characterized by unique features related to the place of origin and traditional know-how. However, the presence of non-authentic products in the market represents a fraud that can be tackled applying analytical techniques combined with chemometric analysis. In this study, we applied multi-element and multi-isotope analysis to characterize PDO and PGI apples cultivated in northern Italy, comparing them with Italian apples without labels of geographical indications.

Results: The multi-element and multi-isotope approach allowed to characterize the apples cultivated in northern Italy. Despite a significant effect of the sampling sites on the apple composition, the comparison of the multi-chemical fingerprint of the apples significantly varied among cultivation areas. Results of this characterization were used to classify samples according to their cultivation area applying a linear discriminant analysis (LDA). Outputs of the LDA showed that correct sample classification can be successfully achieved (balanced accuracy > 96%). Moreover, using a selection of variables, it was possible to correctly classify samples also at regional level.

Conclusion: The presented evidences indicate that the multi-element and multi-isotope fingerprint can be successfully applied to traceability studies. The combination of this characterization with chemometric tools allows the classification of Italian apples based on their origin both on a national and regional scale. This approach represents an interesting tool to enhance and protect PDO and PGI Italian products. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Keywords: PDO and PGI labels; geographical origin; isotope ratio; linear discriminant analysis; mass spectrometry; multi-element analysis.

Publication types

  • Evaluation Study

MeSH terms

  • Discriminant Analysis
  • Food Analysis / methods*
  • Fruit / chemistry
  • Fruit / classification
  • Geography
  • Isotopes / chemistry
  • Italy
  • Malus / chemistry*
  • Malus / classification
  • Mass Spectrometry / methods*

Substances

  • Isotopes