Enhancing mass spectrometry interpretability by ComDim-ICA multi-block analysis: Geographical and varietal traceability of Brazilian Coffea canephora

Author(s)

Baqueta, Michel Rocha ; Pallone, Juliana Azevedo Lima ; Pilau, Eduardo Jorge ; Goulartc, Bruno Henrique Fermino ; Rocha, Rodrigo Barros ; Valderrama, Patricia ; Rutledge, Douglas N.

• Document type: Journal article
• Source: Talanta; v. 281, p. 9-pg., 2024-09-21.

Abstract

Mass spectrometry can gain analytical interpretability by studying complementarity and synergy between the data obtained by the same technique. To explore its potential in an untargeted metabolomic application, the objective of this work was to obtain organic and aqueous coffee extracts of three coffee Canephora groups produced in Brazil with distinctive aspects: geographical origin and botanical variety. Aqueous and organic extracts of roasted coffee beans were analyzed by direct infusion electrospray ionization mass spectrometry. Due to the large number of samples, the injector of the liquid chromatography system was used to automate the analysis. The column was removed, and a peak tube was added to connect the system directly to the mass spectrometer to inject both polar and nonpolar fractions of the coffee extracts individually. The technique provided characteristic fingerprinting mass spectra that not only allowed for differentiation of geographical origins but also between robusta and conilon botanical varieties. The mass spectra of the organic and water extracts represented two separate data blocks to be analyzed by the ComDim-ICA multi-block data analysis method. While the classical ComDim is based on applying PCA to the iteratively reweighted concatenated matrices, in the ComDim-ICA, the factorization is done using independent components analysis, which promotes specific improvements since it is based on extracting components that are statistically independent of one another. The results highlighted by ComDim-ICA show that both water and organic extracts contributed with important ions to the characterization of the coffee composition. However, the results revealed a high variability of metabolomic composition within each botanical variety (Robusta Amaz & ocirc;nico and Conilon Capixaba) and geographical provenance (Rond & ocirc;nia indigenous-1, Rond & ocirc;nia non-indigenous-2 and Esp & iacute;rito Santo-3). Even so, water mass spectra differentiated the botanical variety Conilon from Robusta based on significant ions related to trigonelline, caffeic acid, caffeoylquinic acid, and methylpyridinium; both water and organic mass spectra differentiated Rond & ocirc;nia indigenous from Rond & ocirc;nia non-indigenous and Esp & iacute;rito Santo Conilon based on significant ions related to benzoic acid, pentose, coumaric acid, caffeine in the organic extract and malonic acid, pentose, caffeoylquinic acid, methyl pyridinium, caffeine, and sucrose present in the water extract. With the proposed approach acquiring ion fingerprints of different coffee extracts and their subsequent analysis by ComDim-ICA, new complementary chemical aspects of Brazilian Coffea canephora were put in evidence. (AU)

• FAPESP's process: 22/04068-8 - Innovative chemometrics-based analytical approaches for the multiplatform evaluation of Brazilian Canephora coffees with geographical indication
• Grantee: Michel Rocha Baqueta
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 22/03268-3 - Alternative analytical techniques and in vitro digestion assays to special foods
• Grantee: Juliana Azevedo Lima Pallone
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/21062-0 - Chemical descriptors and emerging green technologies combined with chemometrics for characterization and evaluation of Brazilian specialty coffees
• Grantee: Michel Rocha Baqueta
• Support Opportunities: Scholarships in Brazil - Doctorate