Classification of Brazilian roasted coffees from different geographical origins and farming practices based on chlorogenic acid profiles

Sabur Badmos^a, Maotian Fu^a, Daniel Granato^b, Nikolai Kuhnert^a

Department of Life Sciences and Chemistry, Jacobs University Bremen, Campus Ring 1, 28759 Bremen, Germany.

Abstract

Sixty-seven roasted coffee samples from different regions of Brazil cultivated using organic, conventional and biodynamic farming practices were analysed and quantified using high performance liquid chromatography coupled with mass spectrometry, and treated with supervised (PLS-DA) and unsupervised (PCA) multivariate statistical tools. The profile of the chlorogenic acids constituents were analysed by high resolution and tandem mass spectrometry, which allowed the identification of mono- caffeoyl-, feruloyl-, para-Coumaroylquinic acids and their respective regio-isomers. This study provides a comprehensive analysis of absolute quantitative data set of chlorogenic acids constituents (CQA, FQA and pCoQA isomers) in Brazilian coffee beans produced from different regions of the country. Variations in the chlorogenic acids compositions were observed if organic and conventional roasted coffee beans were compared. The use of multivariate statistical tools allowed the identification of suitable biomarkers for determining significant differences between the three coffee agricultural practices, while coffees produced from the diverse geographical regions showed no significant difference.

Keywords: Coffee, Mass spectrometry, Polyphenols, Chlorogenic acids, Multivariate statistics, Chemometrics, Organic farming, Conventional farming, Geographical origin.