title: Modelling Extraction of White Tea Polyphenols: The Influence of Temperature and Ethanol Concentration.
abstract: The optimization of the extraction of natural antioxidants from white tea has fostered intensive research. This study has investigated the effects of ethanol-water mixtures, temperature and time on the extraction of polyphenols and antioxidant components from white tea. The response surface methodology was applied to identify the best extraction conditions. The best conditions to maximize the extraction of total polyphenols were: ethanol, 50%, for 47.5 min. Although the yield of polyphenols was optimal at 65 °C, the maximum antioxidant capacity was achieved with an extraction temperature of 90 °C. This study has identified the optimal conditions for the extraction of tea liquor with the best antioxidant properties. Epigallocatechin gallate, epicatechin gallate, epigallocatechin and epicatechin were extracted from white tea at concentrations up to 29.6 ± 10.6, 5.40 ± 2.09, 5.04 ± 0.20 and 2.48 ± 1.10 mg/100 g.
authors.affiliation: Department of Health Microbiology and Parasitology, Faculty of Pharmacy, Barcelona University, Avenue Joan XXIII s/n, 08028 Barcelona, Spain. segoviafj@gmail.com.|IRIS-Innovació I Recerca Industrial i Sostenible, Avda. Carl Friedrich Gauss nº11, 08860 Barcelona, Spain. segoviafj@gmail.com.|Chemical Engineering Department, Technical University of Catalonia, Avda Diagonal 647, 08028 Barcelona, Spain. segoviafj@gmail.com.
authors.forename: Sara
authors.initials: S
authors.lastname: Peiró
authors.affiliation: Department of Food and Nutritional Science, University of Reading, Whiteknights, P.O. Box 226, Reading RG6 6AP, UK. m.h.gordon@reading.ac.uk.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Gordon
authors.affiliation: Department of Applied Mathematics III, Technical University of Catalonia, ESAB, Campus del Baix Llobregat, Esteve Terradas 8, 08860 Barcelona, Spain. monica.blanco@upc.edu.
authors.forename: Mónica
authors.initials: M
authors.lastname: Blanco
authors.affiliation: Department of Physiology and Pharmacology, School of Biology, University of Murcia, Campus de Espinardo, 30100 Murcia, Spain. frapella@um.es.
authors.forename: Francisca
authors.initials: F
authors.lastname: Pérez-Llamas
authors.affiliation: Chemical Engineering Department, Technical University of Catalonia, Avda Diagonal 647, 08028 Barcelona, Spain. segoviafj@gmail.com.
authors.forename: Francisco
authors.initials: F
authors.lastname: Segovia
authors.affiliation: Chemical Engineering Department, Technical University of Catalonia, Avda Diagonal 647, 08028 Barcelona, Spain. m.pilar.almajano@upc.edu.
authors.forename: María Pilar
authors.initials: MP
authors.lastname: Almajano
keywords: MECK; RSM; antioxidant; extraction; polyphenols; white tea