title: Antioxidant phenolic extracts obtained from secondary Tunisian date varieties (Phoenix dactylifera L.) by hydrothermal treatments.
abstract: Three common non-commercial Tunisian date varieties were treated by two thermal systems, obtaining a liquid fraction which was characterized and its antioxidant capacity determined. The concentration of total phenols in the three varieties (Smeti, Garen Gazel, and Eguwa) was increased by steam explosion treatment up to 5311, 4680, and 3832 mg/kg of fresh dates, and their antioxidant activity up to 62.5, 46.5 and 43.1 mmol Trolox/kg of fresh date, respectively. Both thermal treatments increased the content of phenolic acids. Additionally, a long scale study was carried out in a pilot plant, with steam treatment at 140 °C and 160 °C for 30 min. The liquid phase was extracted and fractionated chromatographically using adsorbent or ionic resins. The phenolic profiles were determined for each fraction, yielding fractions with interesting antioxidant activities with EC50 values of up to 0.08 mg/L or values of TEAC of 0.67 mmol Trolox/g of extract.
authors.affiliation: Instituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC), Campus Universitario Pablo de Olavide, Edificio 46, Ctra. de Utrera, km. 1, 41013 Seville, Spain; University of Liege - Gembloux Agro-Bio Tech, Department Agro-Bio-Chem, Passage des Déportés, 2, B-5030 Gembloux, Belgium.
authors.forename: Abdessalem
authors.initials: A
authors.lastname: Mrabet
authors.affiliation: Instituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC), Campus Universitario Pablo de Olavide, Edificio 46, Ctra. de Utrera, km. 1, 41013 Seville, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Jiménez-Araujo
authors.affiliation: Instituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC), Campus Universitario Pablo de Olavide, Edificio 46, Ctra. de Utrera, km. 1, 41013 Seville, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Fernández-Bolaños
authors.affiliation: Instituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC), Campus Universitario Pablo de Olavide, Edificio 46, Ctra. de Utrera, km. 1, 41013 Seville, Spain.
authors.forename: Fátima
authors.initials: F
authors.lastname: Rubio-Senent
authors.affiliation: Instituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC), Campus Universitario Pablo de Olavide, Edificio 46, Ctra. de Utrera, km. 1, 41013 Seville, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Lama-Muñoz
authors.affiliation: University of Liege - Gembloux Agro-Bio Tech, Department Agro-Bio-Chem, Passage des Déportés, 2, B-5030 Gembloux, Belgium.
authors.forename: Marianne
authors.initials: M
authors.lastname: Sindic
authors.affiliation: Instituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC), Campus Universitario Pablo de Olavide, Edificio 46, Ctra. de Utrera, km. 1, 41013 Seville, Spain. Electronic address: guirogu@cica.es.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Rodríguez-Gutiérrez
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D062385:Hydroxybenzoates / Q000737:chemistry*; D010636:Phenols; D065749:Phoeniceae / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D062385:Hydroxybenzoates; D010636:Phenols; D010936:Plant Extracts; C017616:phenolic acid
keywords: Antioxidant; Date; Phenolic extract; Thermal treatment