title: α-Tocopherol and fatty acids contents of some Tunisian table olives (Olea europea L.): Changes in their composition during ripening and processing.
abstract: An experimental investigation was carried out on Tunisian olive-fruits of Meski, Sayali and Picholine cultivars. α-Tocopherol and fatty acids (FA) contents were analyzed, during both ripening and processing, according to the Spanish style. The relationship between oil, unsaponifiable and α-tocopherol contents was determined only during ripening. A genetic effect on FA composition was observed throughout the sampling periods. The highest oleic acid content was found in Sayali cultivar at green stage (78.5% of total FA). α-Tocopherol was positively correlated with unsaturated FA content (R=0.71, p<0.05), and oil amount (R=0.984; R=0.976; R=0.952, p<0.05 for Picholine, Sayali and Meski, respectively), but it was not correlated with unsaponifiable matter. In processed olive-fruits, the results showed primarily, that processing according to the Spanish style is not restricted to green olive-fruits but can be successfully used in cherry olives with guaranteed quality and nutritional value of processed product (Meski and Picholine) related to FA content. Secondly, both α-tocopherol and FA amounts decreased during processing for all cultivars. This decrease was cultivar dependent. It was more pronounced in the black fruit than in the green one for the same cultivar. During fermentation, pH variation showed the same profile in all cultivars. Final pH values at the end of fermentation depend on the concentration of free FA (acidity) in the brine.
authors.affiliation: Laboratoire de Biochimie des Lipides, Département de Biologie, Faculté des Sciences de Tunis, 2092 El Manar II, Tunisia. Electronic address: Faouzi.Sakouhi@fst.rnu.tn.
authors.forename: Faouzi
authors.initials: F
authors.lastname: Sakouhi
authors.affiliation: Laboratoire de Biochimie des Lipides, Département de Biologie, Faculté des Sciences de Tunis, 2092 El Manar II, Tunisia.
authors.forename: Saoussem
authors.initials: S
authors.lastname: Harrabi
authors.affiliation: Centre d'Etude Structurale et d'Analyse des Molécules Organiques, Institut des Sciences Moléculaires, Université de Bordeaux1, 351, Cours de la Libération, 33405 Bordeaux, France.
authors.forename: Cristelle
authors.initials: C
authors.lastname: Absalon
authors.affiliation: Laboratoire de Biochimie des Lipides, Département de Biologie, Faculté des Sciences de Tunis, 2092 El Manar II, Tunisia.
authors.forename: Khaled
authors.initials: K
authors.lastname: Sbei
authors.affiliation: Laboratoire de Biochimie des Lipides, Département de Biologie, Faculté des Sciences de Tunis, 2092 El Manar II, Tunisia.
authors.forename: Sadok
authors.initials: S
authors.lastname: Boukhchina
authors.affiliation: Laboratoire de Biochimie des Lipides, Département de Biologie, Faculté des Sciences de Tunis, 2092 El Manar II, Tunisia.
authors.forename: Habib
authors.initials: H
authors.lastname: Kallel
keywords: Anaerobic processes; Cherry olives; Fatty acids; Ripening; Table olive; α-Tocopherol