title: Application of FTIR-ATR to Moscatel dessert wines for prediction of total phenolic and flavonoid contents and antioxidant capacity.
abstract: Fourier transform infrared spectroscopy (FTIR) attenuated total reflectance (ATR) was applied for the determination of total phenolic and flavonoid contents and antioxidant capacity (DPPH and FRAP assays) in Moscatel dessert wines (n=56). Prediction models were developed for the referred parameters using Partial Least Squares (PLS) considering the spectral region 1800-900cm(-1). The determination coefficients (r(2)) values in the calibration models ranged from 0.670 to 0.870. Cross validation (leave-one-out technique) was applied to the data. Root mean square errors of calibration (RMSEC) and cross validation (RMSECV) as well as the relative errors of prediction (REP) were calculated. Minimum errors of prediction were obtained for total flavonoid content (0.2%) and maximum values (22%) for antioxidant capacity measured by FRAP. The proposed method may be used for rapid screening of total phenolic and flavonoid contents in Moscatel dessert wines. The implemented methodologies may also be used to get rough estimates for DPPH and FRAP antioxidant capacities.
authors.affiliation: Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780 - 901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica, Av. da República, Estação Agronómica Nacional, 2780-157 Oeiras, Portugal. Electronic address: ssilva@itqb.unl.pt.
authors.forename: Sandra D
authors.initials: SD
authors.lastname: Silva
authors.affiliation: Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780 - 901 Oeiras, Portugal.
authors.forename: Rodrigo P
authors.initials: RP
authors.lastname: Feliciano
authors.affiliation: Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780 - 901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica, Av. da República, Estação Agronómica Nacional, 2780-157 Oeiras, Portugal.
authors.forename: Luís V
authors.initials: LV
authors.lastname: Boas
authors.affiliation: Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780 - 901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica, Av. da República, Estação Agronómica Nacional, 2780-157 Oeiras, Portugal; Faculdade de Farmácia de Lisboa, Av. das Forças Armadas, 1649 - 019 Lisboa, Portugal.
authors.forename: Maria R
authors.initials: MR
authors.lastname: Bronze
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D005419:Flavonoids / Q000032:analysis*; D010636:Phenols / Q000032:analysis*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D014920:Wine / Q000032:analysis*
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols
keywords: Antioxidant capacity; Fourier-transform infrared spectroscopy; Moscatel wine; Phenolic compounds