Quality evaluation of cork from Quercus suber L. by the electronic tongue Original Research Article

The aim of the present study was application of the electronic tongue multisensor system (ET) for discrimination of cork both standard and Mancha Amarela (Yellow spot). Extracts of cork in 10% ethanol water solutions were analysed. Two sets of cork samples that included both standard (S) and Mancha Amarela (MA) cork samples from two different factories were studied. It was found that ET could reliably distinguish extracts made from S and MA cork regardless samples’ origin. ET could predict total phenols’ content with average precision of 9% when calibrated using reference data obtained by Folin–Ciocalteu method. The ET was demonstrated to be promising tool for the cork quality evaluation. Difference in composition between S and MA cork was studied by ET. The largest difference in concentration between two types of cork extracts was found for gallic and protocatechuic acids.