title: How heating affects extra virgin olive oil quality indexes and chemical composition.
abstract: Two monovarietal extra virgin olive oils from Arbequina and Picual cultivars were subjected to heating at 180 degrees C for 36 h. Oxidation progress was monitored by measuring oil quality changes (peroxide value and conjugated dienes and trienes), fatty acid composition, and minor compound content. Tocopherols and polyphenols were the most affected by the thermal treatment and showed the highest degradation rate although their behavior was different for each cultivar. Alpha-tocopherol loss was more important in Arbequina oil whereas, total phenol content loss was greater in Picual oil. The later showed an important decrease in hydroxytyrosol (3,4-DHPEA) and its secoiridoid derivatives (3,4-DHPEA-EDA and 3,4-DHPEA-EA), while lignans decrease was lesser. For Arbequina oil these compounds remained stable, and a lowering tendency was observed for tyrosol (p-HPEA) and its derivatives (p-HPEA-EDA and p-HPEA-EA). In general, flavone content showed a decrease during heating, being higher for Arbequina oil. On the other hand, oleic acid, sterols, squalene, and triterpenic alcohols (erythrodiol and uvaol) and acids (oleanolic and maslinic) were quite constant, exhibiting a high stability against oxidation. From these results, we can conclude that despite the heating conditions, VOO maintained most of its minor compounds and, therefore, most of its nutritional properties.
authors.affiliation: Estación de Olivicultura y Elaiotecnia, CIFA Venta del Llano, Instituto Andaluz de Investigación y Formación Agraria, Pesquera, Alimentaría y de la Producción Ecológica (IFAPA), Mengibar, Jaén E-23620, Spain. yosra.allouche.ext@juntadeandalucia.es
authors.forename: Yosra
authors.initials: Y
authors.lastname: Allouche
authors.forename: Antonio
authors.initials: A
authors.lastname: Jiménez
authors.forename: José Juan
authors.initials: JJ
authors.lastname: Gaforio
authors.forename: Marino
authors.initials: M
authors.lastname: Uceda
authors.forename: Gabriel
authors.initials: G
authors.lastname: Beltrán
mesh_terms: D002851:Chromatography, High Pressure Liquid; D005227:Fatty Acids / Q000032:analysis; D005419:Flavonoids / Q000032:analysis; D006358:Hot Temperature; D000069463:Olive Oil; D010084:Oxidation-Reduction; D010636:Phenols / Q000032:analysis; D010938:Plant Oils / Q000737:chemistry*; D059808:Polyphenols; D011786:Quality Control; D024502:alpha-Tocopherol / Q000032:analysis
chemical_list: D005227:Fatty Acids; D005419:Flavonoids; D000069463:Olive Oil; D010636:Phenols; D010938:Plant Oils; D059808:Polyphenols; D024502:alpha-Tocopherol