Principales maderas tropicales utilizadas en España: Características, tecnología y aplicaciones

Se describen las características de las principales maderas tropicales con uso en España. La descripción incluye el nombre científico, sinonimias, nombres vulgares, su distribución en el mundo y en España, la descripción del fuste y de las trozas, con sus defectos más característicos, la descripción de la madera, sus características físicas, mecánicas, resistentes y durables. También se incluye sus aspectos tecnológicos, en el sentido de indicar que aspectos deben considerarse a la hora de trabajar estas maderas. Por último se indican los usos más comunes de las distintas maderas, las ventajas e inconvenientes frente a otras maderas Las especies principales que se describen son las siguientes: Algarrobo blanco, Prosopis alba, Grisebach Andiroba, Carapa guianensis, Aubl. Balsamo, Myroxylon balsamun, Harms. Sandwith. Barba jolote, Pithecolobium arboreum (L), Urban. Bubinga, Guibourtia tessmanii Caoba, Swietenia macrophylla, King. Cedro, Cedrela odorata, L. Cenizaro, Pithecellobium saman, (Jacq.) Benth Chinchon, Guarea grandiflora, A. DC. Cocobolo, Dalbergia retusa, Hemsl Cristobal, Platysmicium polystachyum Elondo o tali, Erythrophleum ivorensis Espavé, Anacardium excelsum, Skeels Gonzalo Alves, Astronium graveolens, Jacquin. Guayabillo, Terminalia lucida, Hoff. Guapaque, Dialium guianense, (Aubl.) Sandwith. Guayacán, Guaiacum sanctum, L. Huesito Homalium racemosum, Jacq. Ipe, Tabebuia guayacan, Hemsl. Iroko, Milicia excelsa Sim Jatoba, Hymenaea courbaril L. Machiche, Lonchocarpus castilloi, Standley. Manil, Symphonia globulifera, L. Marupa, Simarouba glauca, DC. Melina, Gmelina arborea, Roxb. Mongoy, Guibourtia ehie J. Léonard Nance, Byrsonima crassifolia (L.), H.B.K. Nazareno, Peltogyne purpurea Nispero, Manilkara zapota, (L.) Van royen. Palo blanco, Cybitax donnell- smith , Seibert. Pino amarillo, Erblichia odorata Piojo, Tapirira guianensis, Aubl. Quaruba, Vochysia guatemalensis, Donnell Smith Quira, Platysmicium pinnatum. Redondo, Magnolia yoroconte, Dandy. Rosul, Dalbergia tucurensis, Donn-Smith. Sande, Brossimiun ssp San juan areno, Ilex ssp. Saqui-saqui, Bombacopsis quinatum, (Jacq.) Dugand Santa maría, Calophyllum brasílíense Camb. Sapelly, Entandrophragma cylindricum Sprague Tamboril, Enterolobium cyclocarpum, Gris Teca, Tectona grandis, L.F.. Ukola, Tieghemella africana Ururucana, Hieronyma alchorneoides, Allem

Characterisation and oxidative stability of speciality plant seed oils

The past decade has seen an influx of speciality plant seed oils arriving into the market place. The need to characterise these oils has become an important aspect of the oil industry. The characterisation of the oils allows for the physical and chemical properties of the oil to be determined. Speciality oils were characterised based on their lipid and fatty acid profiles and categorised as monounsaturated rich (oleic acid as the major acyl components e.g. Moringa and Marula oil), linoleic acid rich (Grape seed and Evening Primrose oil) or linolenic acid rich (Flaxseed and Kiwi oil). The quality of the oils was evaluated by determining the free fatty acid content, the peroxide value (that measures initial oxidation) and p-anisidine values (that determines secondary oxidation products containing the carbonyl function). A reference database was constructed for the oils in order to compare batches of oils for their overall quality including oxidative stability. For some of the speciality oils, the stereochemistry of the triacylglycerols was determined. Calophyllum, Coffee, Poppy and Sea Buckthorn oils stereochemistry was determined. The oils were enriched with saturated and/or a monounsaturated fatty acids at position sn-1 and sn-3. The sn-2 position of the four oils was esterified with a polyunsaturated and/or a monounsaturated fatty acid indicating that they follow a typical acylation pathway and no novel acylation activity was evident from these studies (e.g enrichment of saturates at the sn-2 position). The oxidative stability of the oils was evaluated at 18oC and 60oC and the effect of adding a-tocopherol at commercially used level i.e 750ppm was assessed. The addition of 750ppm of a-tocopherol at 18oC increased the oxidative stability of Brown flax, Moringa, Wheat germ and Yangu oils. At 60oC Brown Flax, Manketti and Pomegranate oil polymerised after 48 hours. The addition of 750ppm a-tocopherol delayed the onset of polymerisation by up to 48 hours in Brown Flax seed oil. Pomegranate oil showed a high resistance to oxidation, and was blended into other speciality oils at 1%. Pomegranate oil increased the oxidative stability of Yangu oil at 18oC. The addition of Pomegranate oil to Wheat germ oil at 60oC, decreased the peroxide content by 10%. In Manketti and Brown Flaxseed oil at elevated temperatures, Pomegranate oil delayed the onset of polymerisation. Preliminary studies of Pomegranate oil blending to Moringa and Borage oil showed it to be more effective than a-tocopherol for certain oils. The antioxidant effects observed following the addition of Pomegranate oil may be due to its conjugated linolenic acid fatty acid, punicic acid.