Berta Baca-Bocanegra, Julio Nogales-Bueno, Francisco J. Rodríguez-Pulido, M. Lourdes González-Miret, José Miguel Hernández-Hierro* and Francisco J. HerediaFood Colour and Quality Laboratory, Department of Nutrition and Food Science, Facultad de Farmacia, Universidad de Sevilla, 41012 Sevilla, Spain. E-mail: jmhhierro@us.es.