title: Determination of sterol and fatty acid compositions, oxidative stability, and nutritional value of six walnut (Juglans regia L.) cultivars grown in Portugal.
abstract: Six cultivars (Franquette, Marbot, Mayette, Mellanaise, Lara, and Parisienne) of walnuts (Juglans regia L.) were collected during the 2001 crop, from Bragança, Portugal. Chemical composition, including moisture, total oil content, crude protein, ash, carbohydrates, and nutritional value, was evaluated. Fat was the predominant component, ranging from 62.3 to 66.5%. Total oil was extracted and analyzed for fatty acids, sterols, oxidative stability, and peroxide value. Fatty acids and sterols were determined by gas-liquid chromatography coupled to a flame ionization detector. Eighteen fatty acids were quantified. Polyunsaturated fatty acids and, in particular, linoleic acid were predominant. Beta-Sitosterol, delta(5)-avenasterol, and campesterol were the major sterols found. Differences were observed among the studied cultivars, especially in peroxide values and in the sterol profile.
authors.affiliation: REQUIMTE, Serviços de Farmacognosia and Bromatologia, Faculdade de Farmácia, Universidade do Porto, R Aníbal Cunha 164, 4050-047 Porto, Portugal.
authors.forename: Joana S
authors.initials: JS
authors.lastname: Amaral
authors.forename: Susana
authors.initials: S
authors.lastname: Casal
authors.forename: José A
authors.initials: JA
authors.lastname: Pereira
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Seabra
authors.forename: Beatriz P P
authors.initials: BP
authors.lastname: Oliveira
mesh_terms: D002241:Carbohydrates / Q000032:analysis; D002849:Chromatography, Gas; D005227:Fatty Acids / Q000032:analysis*; D031324:Juglans / Q000737:chemistry*; D009753:Nutritive Value; D009754:Nuts / Q000737:chemistry*; D010084:Oxidation-Reduction; D010840:Phytosterols / Q000032:analysis*; D010938:Plant Oils / Q000032:analysis; D010940:Plant Proteins / Q000032:analysis; D011174:Portugal
chemical_list: D002241:Carbohydrates; D005227:Fatty Acids; D010840:Phytosterols; D010938:Plant Oils; D010940:Plant Proteins