A novel approach for honey pollen profile assessment using an electronic tongue and chemometric tools Luís G. Dias a, b, ** , Ana C.A. Veloso c, d , Mara E.B.C. Sousa e , Letícia Estevinho e , Ad  elio A.S.C. Machado f , Ant  onio M. Peres g, * a Escola Superior Agr aria, Instituto Polit ecnico de Bragança, Campus Santa Apol onia, 5301-855 Bragança, Portugal b CQ-VR, Centro de Química e Vila Real, University of Tr as-os-Montes e Alto Douro, Apartado 1013, 5001-801 Vila Real, Portugal c Instituto Polit ecnico de Coimbra, ISEC, DEQB, Rua Pedro Nunes, Quinta da Nora, 3030-199 Coimbra, Portugal d CEB-Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal e CIMO-Escola Superior Agr aria, Instituto Polit ecnico de Bragança, Campus Santa Apol onia, 5301-855 Bragança, Portugal f LAQUIPAI e Laborat orio de Química Inorg^ anica Pura e de Aplicaç~ ao Interdisciplinar, Departamento de Química, Faculdade de Ci^ encias da, Universidade do Porto, Rua Campo Alegre n  . 687, 4169-007 Porto, Portugal g LSRE-Laboratory of Separation and Reaction Engineering-Associate Laboratory LSRE/LCM, Escola Superior Agr aria, Instituto Polit ecnico de Bragança, Campus Santa Apol onia, 5301-855 Bragança, Portugal highlights graphical abstract  Honey's floral origin labeling is a legal requirement.  Melissopalynology analysis usually used to evaluate pollens profile is laborious.  A novel E-tongue based approach is applied to assess pollens relative abundance.  MLR models using SA variable selec- tion and repeated K-fold cross- validation.  The approach may be used as a pre- liminary tool for pollinic evaluation. article info Article history: Received 22 November 2014 Received in revised form 3 March 2015 Accepted 21 October 2015 Available online 24 October 2015 Keywords: Electronic tongue Multiple linear regression models Simulated annealing algorithm Honey Pollen profile abstract Nowadays the main honey producing countries require accurate labeling of honey before commercial- ization, including floral classification. Traditionally, this classification is made by melissopalynology analysis, an accurate but time-consuming task requiring laborious sample pre-treatment and high- skilled technicians. In this work the potential use of a potentiometric electronic tongue for pollinic assessment is evaluated, using monofloral and polyfloral honeys. The results showed that after splitting honeys according to color (white, amber and dark), the novel methodology enabled quantifying the relative percentage of the main pollens (Castanea sp., Echium sp., Erica sp., Eucaliptus sp., Lavandula sp., Prunus sp., Rubus sp. and Trifolium sp.). Multiple linear regression models were established for each type of pollen, based on the best sensors' sub-sets selected using the simulated annealing algorithm. To minimize the overfitting risk, a repeated K-fold cross-validation procedure was implemented, ensuring that at least 10e20% of the honeys were used for internal validation. With this approach, a minimum average determination coefficient of 0.91 ± 0.15 was obtained. Also, the proposed technique enabled the correct classification of 92% and 100% of monofloral and polyfloral honeys, respectively. The quite satisfactory performance of the novel procedure for quantifying the relative pollen frequency may * Corresponding author. Escola Superior Agr aria, Instituto Polit ecnico de Bragança, Campus Santa Apol onia, 5301-855 Bragança, Portugal. ** Corresponding author. Escola Superior Agr aria, Instituto Polit ecnico de Bragança, Campus Santa Apol onia, 5301-855 Bragança, Portugal. E-mail addresses: ldias@ipb.pt (L.G. Dias), peres@ipb.pt (A.M. Peres). Contents lists available at ScienceDirect Analytica Chimica Acta journal homepage: www.elsevier.com/locate/aca http://dx.doi.org/10.1016/j.aca.2015.10.014 0003-2670/© 2015 Elsevier B.V. All rights reserved. Analytica Chimica Acta 900 (2015) 36e45