  Improvement of the Composition of Tunisian Myrtle Berries (Myrtus 2 communis L.) Alcohol Extracts; ; et al in Journal of Agricultural and Food Chemistry (2011), 3b2(9), Detailed reference viewed: 10 (4 ULg)Pectin extraction from lemon by-product with acidified date juice : effect of extraction conditions on chemical composition of pectin.; ; et al in Food Science & Technology International (2010), 16(2), 105-114 The microstructure and the rheological properties of lemon-pectin mixtures were studied and compared to those of pure lemon (high methoxyl: HM) and date (low methoxyl: LM) pectins. Rheological properties ... [more ▼] The microstructure and the rheological properties of lemon-pectin mixtures were studied and compared to those of pure lemon (high methoxyl: HM) and date (low methoxyl: LM) pectins. Rheological properties were carried out in the presence of 30%, 45% and 60% sucrose, and increasing calcium concentrations (0-0.1%). The presence of date with lemon pectin led to a gel formation at 45% sucrose and in the presence of calcium, which was not the case for lemon pectin alone under the same conditions. It is suggested that lemon and date pectins interacted, leading to gel formations at different gelling temperatures, which were strongly dependant on degree of methylation. These results were confirmed by scanning electron microscopy, which revealed inhomogeneous gels where dense aggregated network and loose, open network areas were present. Addition of calcium to pectin mixture gels led to stronger and faster gel formation. [less ▲] Detailed reference viewed: 60 (15 ULg)Chemical Composition and Antioxydant Activity of Laurus nobilis Floral Buds Essential Oil; ; et al in Journal of Essential Oil Research (2009) The essential oil of Laurus nobilis floral buds (FB) collected in Tunisia was obtained by hydrodistillation and analysed by GC-MS. Twenty three constituents were identified. The main components of this ... [more ▼] The essential oil of Laurus nobilis floral buds (FB) collected in Tunisia was obtained by hydrodistillation and analysed by GC-MS. Twenty three constituents were identified. The main components of this oil were α-terpinyl acetate (28.43 %), methyl eugenol (19.57 %), eugenol (7.42 %) and elemicin (4.41 %). The antioxidant activity of the oil of Laurus nobilis FB was evaluated by two methods, β-carotene bleaching (BCB) test and 2.2-diphenyl-β-picrylhydrazyl (DPPH) assay using respectively butylated hydroxytoluene (BHT), trolox, gallic acid, caffeic acid and δ-tocopherol as standards. It was found that the Laurus nobilis FB oil have a significant antioxidant effect when tested by each method respectively. The antioxidant activity of this oil is more effective than the synthetic antioxidant (BHT) at 200 ppm and can be attributed to the active compounds eugenol, elemicin and methyl eugenol present in this essential oil. [less ▲] Detailed reference viewed: 147 (8 ULg) |
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