102 research outputs found
Tahitian Vanilla (Vanilla ×tahitensis): A Vanilla Species with Unique Features
This chapter reviews the main findings on Tahitian vanilla (Vanilla ×tahitensis) over the last 10 years. It brings new insights into the hybrid origin of V. ×tahitensis and its diversification in French Polynesia. It details then the different analytical methods used to characterize the flavour properties and the aroma impact compounds of Tahitian vanilla, with a special emphasis on how they can be used to differentiate Tahitian vanilla from other vanillas. Finally, the effect of the curing process on the chemical composition and the sensory properties is discussed. These results highlight the need to include some of the key volatile compounds into a more adapted quality control, in order to describe the characteristic sensory properties of Tahitian vanilla but also those from other origins
Comparison of teak wood properties according to forest management: short versus long rotation
Key message: Teak (Tectona grandis L.f.) is one of the most important tropical hardwood tree species, which is widely planted in Indonesia. Wood properties are strongly influenced by forest management conditioning further utilization of wood. Context: In Indonesia, teak wood has been supplied from the state forests (Perhutani) for long rotation teak and from community teak plantations for short rotation teak. Short rotation teak has been harvested at 7–10 years and long rotation teak at 40–60 years. Aims: This paper discusses the characterization of technical properties of short and long rotation teak wood based on the chemical, anatomical, physical, and mechanical properties. Methods: The properties of short rotation and long rotation teak woods were characterized by measuring their density, extractive contents, chemical composition, swelling, wettability, water sorption isotherm, decay resistance, anatomical properties, bending strength (modulus of rupture (MOR), modulus of elasticity (MOE)), and hardness. Results: The results indicate that short rotation teak was not particularly different in swelling, MOE and MOR, and Brinell hardness compared to long rotation teak, although it was less dense and less durable due to lower heartwood and extractive contents. Therefore, careful attention should be given to the use of short rotation teak in some wood-processing technologies. Conclusion: Lower wood density and durability of the short rotation compared to the long rotation teak will restrict its utilization to some extent for both indoor and outdoor applications. Fast-growing teak from community cannot be used as usual heartwood teak from Perhutani because of the very low proportion of useful heartwood in the stem
Characterization of bark extractives of different industrial Indonesian wood species for potential valorization
Barks are available as waste material and by-product of wood industry. They have been reported to contain interesting molecules and show some bioactivity such as antioxidant and antifungal. This study aimed at evaluating the amounts of extractives in Acacia mangium (acacia), Paraserianthes falcataria (sengon) and Swietenia mahagoni (mahoni) barks, to evaluate their extractive contents and the presence of potential valuable molecules. The extraction method used soxhlet with four different solvents. Antioxidant activity assays were carried out using methyl linoleate and 2,2-diphenyl-1-picrilhidrazyl (DPPH) and the antifungal activity was determinate by fungal growth inhibitions assays. 5.3%–18.5% extraction yields were obtained. All acetone and toluene ethanol extracts show high antioxidant activity by DPPH. The highest antioxidant value obtained by DPPH was obtained for mahoni bark acetone extract with 3.9 mg/L of EC50, followed by mahoni bark toluene ethanol 6.8 mg/L, acacia bark acetone 7 mg/L, and acacia bark toluene ethanol extract 7.4 mg/L. Sengon bark extracts had the greatest antifungal activity inhibition. The greatest antioxidant and antifungal activity were obtained with phenolic compounds which were contained in the extracts
Oil composition of the sandalwood (Santalum austrocaledonicum) from Erromango and Aniwa islands, Vanuatu
The essentiel oil composition of 16 wood samples from Erromango and Aniwa has shown important differences between a group where the individual variability is high and 2 individual samples. Considering that alpha-santalol and beta-santalol are the most important molecules in the Indian sandal oil, this group presents a surprisingly low content of these components (20%-30%) whereas one of the individual samples has a content of 70%, similar to the New Caledonian S. #austrocaledonicum# and the standard #S. album# sandal oil. There are two significantly distinct chemotypes. This difference leads to several questions to which the present sampling can only reply partially : where does this difference come from ? (particularities of the stands, environmental characteristics, characteristics of the tree...) If the chemotypes cannot be linked to the stand, is the 1/15 ratio significative of the population ? The answers to these two questions are of prime importance for future germplasm conservation and strategies of tree propagation for a planting policy. The selection of germplasm, the sandal oil content of which is not similar to the standard one presently known on the market, would lead to lower prices for the wood although the best pieces will always find buyers at a good price. A large and systematic survey of all the stands on all the islands is therefore recommended in order to identify the real oil variation determinism. (Résumé d'auteur
Partage d'expériences en matière de recueil de savoirs traditionnels et d'étude des activités biologiques de plantes liées à ces savoirs
International audienc
Partage d'expériences en matière de recueil de savoirs traditionnels et d'étude des activités biologiques de plantes liées à ces savoirs
International audienc
Glucosinolates in three Brassicales of French Polynesia
International audienc
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