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International audience; The effect of toasting method and forest origin on volatile compounds and ellagitannin concentration extracted into Merlot wine during 1-year barrel maturation is described. Sensory analysis concerning vanilla, spicy, overall woody, astringency, bitterness and sweetness is conducted in parallel. The study is realized in two different experimental designs having only a common parameter, the wine. For the first one, common toasting methods (light, medium) and specific ones (medium toast with watering, medium plus toast, medium plus toast with watering, medium toast with toasted head and Noisette) are chosen. For the second one, the oak from which barrels are made is sourced from Center, Limousin, Allier and Colbert forests in France, from Pennsylvania forest in America, and from Slavonia forest in East Europe. Wine with different characteristics is obtained from the same wine in relation to forest origin and toasting process. Watering process during toasting enhances furanic compounds vanillin and oak lactones extraction, whereas toasting barrel head pieces may lead to eugenol and ellagitannin degradation. Wine in light toast barrel is perceived as less sweet, bitter and more astringent. Ellagitannin concentration is closely correlated to astringency, reflecting the relationship between them, R = 0.599, p < 0.001. Forest origin induces important changes; wine in American barrels is differentiated from those in Slavonia and French barrels. Ellagitannin concentration in barrels from Slavonia is halfway between French and American, and ellagitannin concentration is related linearly to astringency intensity (R = 0.811, p < 0.001). Wine aged in Slavonia showed characteristics similar and intermediate to those of the same wine aged in French and American oak woods, suggesting that they are suitable for barrel production of quality wine.

Изменения в структуре древесины дуба под влиянием ультразвука изучались методом термомеханической спектрометрии. Установлены различия молекулярно-релаксационных характеристик древесины в аксиальном и радиальном направлениях относительно роста дерева до и после воздействия ультразвука. Реакция структурных блоков на действие ультразвука обусловлена пространственным расположением морфологических элементов древесины и их размерами относительно оси дерева и надмолекулярным строением составляющих их полимеров., Structural changes in oak wood under the effect of ultrasound were studied by the method of thermomechanical spectroscopy. Molecular-relaxational characteristics of oak wood into axial and radial directions respectively to tree axis growth before and after the effect of ultrasound were examined. The reactions of structural block have been found to depend on spatial distribution of morphological elements of wood and theirs sizes with regard to the axis’s of tree and under molecular structure of polymers.

This work studied the influence of the composition of wine on the evolution of oak compounds and on esters in red wines aged in American oak barrels. For this purpose, two of the most utilized grape varieties in wine-making, Merlot and Cabernet Sauvignon, were used. The wines made with these two varieties showed differences in pH and alcoholic degree. The extraction of furanic aldehydes, oak lactones, phenolic aldehydes and phenolic alcohols was higher in the Merlot wine, with higher alcoholic degree, than in the Cabernet Sauvignon wine, with lower pH. The difference in the concentration of these compounds in both wines was important up to 10-12 months of ageing, as afterwards most of these compounds were degraded. The evolution of fermenting esters was not affected by the composition of wine. © 2004 Elsevier Ltd. All rights reserved.

A red Rioja wine was aged in barrels made of Spanish oak wood (Quercus robur, Quercus petraea,Quercus pyrenaica, and Quercus faginea) during 21 months. The concentrations of some volatile compounds [syringaldehyde, vanillin, eugenol, maltol, guaiacol, 4-ethylphenol, cis and trans isomers of beta-methyl-gamma-octalactone, 2-furfuraldehyde, 5-methyl-2-furfuraldehyde, 5-(hydroxymethyl)-2-furfuraldehyde, and furfuryl alcohol] were studied in these wines and compared with those of the same wine aged in barrels made from French oak of Q. robur (Limousin, France) and Q. petraea (Allier, France) and American oak of Quercus alba (Missouri). Similar concentrations of these compounds were found in wines aged in Spanish and French oak wood barrels, and significantly different concentrations were found with respect to wines aged in barrels made of American oak wood, indicating a different behavior. Thus, wines with different characteristics were obtained, depending on the kind of wood. Also, the kind of wood had an important influence on sensory characteristics of wine during the aging process. Spanish oak wood from Q. robur, Q. petraea, and Q. pyrenaica can be considered to be suitable for barrel production for quality wines, because a wine aged in barrels made of these Spanish oak woods showed similar and intermediate characteristics to those of the same wine aged in French and American oak woods usually used in cooperage.

Hrastovino uvrščamo med najbolj trajne slovenske lesne vrste. V literaturi in tudi na osnovi praktičnih izkušenj smo opazili, da naravna odpornost hrastovine močno niha. Do sedaj je večina strokovnjakov naravno odpornost hrastovine povezovala z vsebnostjo ekstraktivov. Dokazali so, da imajo ekstraktivi velik vpliv na naravno odpornost, vendar samo s tem parametrom niso mogli pojasniti razlik glede obnašanja vzorcev. Da bi ugotovili, kako na odpornost hrastovine vpliva širina branik oziroma gostota, smo, v skladu s standardom SIST EN 113, izdelali vzorce iz hrastovih desk različnih širin branik in jih izpostavili 5 vrstam gliv. Vzporednim vzorcem smo določili delež ekstraktivov, dušika, lignina, kemijsko analizo (FTIR) in barvo. Iz gravimetrično določene izgube mase in mikroskopske analize razkrojenih vzorcev lahko sklepamo, da so bili hrastovi vzorci iz ozkih branik bolj dovzetni na glivni razkroj kakor vzorci iz srednje širokih in širokih branik. Odpornost hrastovine s povprečno širino branik 0,77 mm je primerljiva z naravno odpornostjo bukovine. Poleg tega naši rezultati potrjujejo, da je vpliv ekstraktivov na naravno odpornost hrastovine zelo pomemben. Oak-wood is considered as one of the most durable Slovenian domestic wood species. There were several reports about natural durability of products made of oak. In the past research on oak-wood durability, the most important factor influencing wood durability was assigned to extractives. It was proved that the extractives had a large influence on natural durability, nevertheless, just this parametre did not suffice to elucidate the differencesregarding the behaviour of samples. To find out if oak-wood durability can also be affected by ring-widths or density, oak-wood specimens were prepared from boards with different ring-widths, and exposed to 5 different fungal species, according to the EN 113 standard procedure. In parallel, extractives, nitrogen, lignin content, chemical properties (FTIR), and colour of the specimens were determined as well. From gravimetrically determined mass losses, and microscopy analysis of decayed specimens, it can be resolved that oak wood specimens with the narrowest rings are more susceptible to fungal decay than specimens made of average or wide ring-widths. Durability of oak-wood with average rings width of 0.77 mm is comparable to durability of beech-wood. Furthermore, our results indicate that influence of extractives on wood durability is important as well.

V podjetju, ki izdeluje kuhinjsko pohištvo, želijo v proizvodnjo vključiti modificiran les, ker je dimenzijsko stabilnejši. S postopkom modifikacije lahko vplivamo tudi na barvo, zato jim modificiranega lesa ne bi bilo treba lužiti. Pri tem pa je pomembno, da so klasični in vodni premazni sistemi kompatibilni z modificiranimi podlagami ter kako lastnosti modificiranega lesa vplivajo na lastnosti površinskega sistema. Na nemodificiranem ter v vakuumu termično (pri temperaturah 150 °C in 200 °C) modificiranem hrastovem lesu, smo preizkušali nekatere lastnosti: debelino, oprijemnost, odpornost proti udarcem, razenju in odpornost robov proti vodi, utrjenih filmov vodnega in poliuretanskega laka ter barvo in sijaj. Ugotovili smo, da je vodni lak slabo odporen proti mehanskim poškodbam ter da vrsta podlage močno vpliva tako na debelino utrjenega filma, na sijaj, kot tudi na odpornostne lastnosti površinskega sistema. Z višanjem temperature modifikacije se te lastnosti slabšajo, zmanjša pa se tudi debelina utrjenega filma. Najslabše lastnosti smo ugotovili pri preizkušancih, modificiranih pri 200 °C, pozitivno je izstopala le odpornost robov proti omočitvi z vodo. Kitchen furniture producer wants to introduce thermally modified wood into their regular production. Thermal modification of wood increases its dimensional stability and influences its colour, so there would be no need to stain it. However, there are questions, whether the classical waterborne coating systems are compatible with the modified substrates, and how the properties of modified wood influence characteristics of the system. Some properties: thickness, adhesion, resistance against impact and scratching, and resistance of edges against water of strengthened films of waterborne and polyurethane coatings were tested on untreated and in vacuum thermally modified (temperatures: 150 °C and 200 °C) oak wood colour and gloss. It was found out that waterborne coatings showed low resistance against mechanical injuries, the type of the substrate influenced the thickness of strengthened film strongly, so as gloss, and properties of surface system. These properties get worse with too high a temperature of modification, also thickness of strengthened film reduces. The worst properties were found in wood samples, modified at 200 °C, the only exception being the resistance of edges against watering.

Zaradi omejitve izpustov hlapnih organskih spojin (HOS) lesnopredelovalne industrije v zrak je treba opraviti še precej raziskav za prehod na površinske premaze z manjšo vsebnostjo HOS. podjetju LIP Radomlje d.d. bi radi nadomestili obstoječe materiale na osnovi organskih topil z ustreznimi premazi na vodni osnovi. Vendar je težava v tem, da obdelujejo masivni les hrasta, ki je za obdelavo z vodnimi sistemi še posebej problematičen (venčastoporozen listavec, vsebuje tanin, itd.). Zamenjava premaza pa privede tudi do potrebne prilagoditve opreme ali celo nakupa nove. Pripravili smo večje število vzorcev iz materialov na vodni osnovi ter jih primerjali s kontrolnimi vzorci, narejenimi iz trenutno uporabljanih materialov. Želeli smo ugotoviti ali že obstajajo premazni materiali na vodni osnovi kot nadomestilo materialov na osnovi organskih topil, primerni tudi za obdelavo masivnega hrastovega lesa. Od vseh testiranih pripravkov smo identificirali 2 kombinaciji, morda primerni za uporabo v proizvodnji (obdelava z vodnim lužilom, vodnim temeljnim lakom in vodnim končnim lakom obdelava z vodnim lužilom, vodnim temeljnim lakom in 2-komponentnim vodnim univerzalnim lakom). Limitation of VOC emissions from wood industries demands extensive research activities in order to introduce surface coatings with a low content of VOCs. LIP Radomlje Company wants to substitute currently used solventbornes with waterborne finnishes. However, they have to coat oak wood which shows specific problems when coated with waterbornes (ring porous hardwood, tannins, etc.). Additional problem is that substitution of coatings may require adaptation of existing coating equipment or even acquisition of the new equipment. Larger number of specimens with waterborne coatings were prepared and compared to control samples, finishes with solventborne coatings. We wanted to find out if waterborne coats could represent a suitable substitution for organic solventborne finishes for oak. Among all the tested formulations 2 combinations could be applicable in the production (waterborne stain, waterborne base coat, waterborne surface finish or waterborne stain, waterborne base coat, 2-pack universal waterborne finish).

Истраживања, спроведена у оквиру докторске дисертације, односе се на домен унапређивања познавања карактеристика и функција обрадљивости храста лужњака (Quercus robur) при обимном глодању. Основни циљ истраживања је био успостављање методологије за одређивање обрадљивости различитих врста дрвећа. Елементи обраде глодањем који су разматрани у дисертацији су брзина помоћног кретања и дубина резања. Испитивања су спроведена за различите геометрије алата. Критеријуми, на основу којих је оцењена обрадљивост дрвета, су снага резања, силе резања и квалитет обрађене површине (храпавост и валовитост). Истраживања су била фокусирана на развој поузданог аналитичког и симулационог модела за анализу и предикцију снаге и сила резање, као и квалитета обрађене површине при уздужном глодању, а на основу хипотезе да ће различити технолошки параметри обраде узроковати и различиту потребну енергију за резање, као и различит квалитет обрађене површине при истој брзини резања. За математичко моделирање, при испитивању критеријума обрадљивости, коришћен је метод тоталних ортогоналних експерименталних планова. Развијени математички модел се користи за одређивање зависности параметара снаге и сила резања, као и квалитета обрађене површине у функцији од режима резања и геометрије алата. Предложени модел се показао као адекватан и са довољном тачношћу описује зависности испитиваних критеријума обрадљивости од изабраних утицајних фактора при усвојеним условима испитивања. Модел се може применити у пракси на одговарајући реални процес обраде обимним глодањем и за подручје варираних улазних фактора. The research of this doctoral dissertation was conducted in the domain of improvement of the knowledge on the properties and functions characterizing the machinability of common oak (Quercus robur) wood during peripheral milling. The main aim of this research was to establish a methodology for determining the machinability of various tree species. The elements of milling considered in this thesis are feed rate and cutting depth. The investigations were carried out for a variety of tool geometries. The criteria for the assessment of the machinability of wood are cutting power, cutting forces and the quality of the processed surface (its roughness and waviness). The research focused on the development of a reliable analytical and simulation model for the analysis and prediction of the cutting power and cutting forces of longitudinal milling, as well as the quality of a surface processed by that machining operation. The basic hypothesis was that different technological parameters of processing result in different amounts of energy needed for cutting, as well as different surface qualities at the same cutting speed. The method of total orthogonal experimental plans was used as the mathematical model for the investigation of the machinability criteria. The developed mathematical model was used for determining the dependence of the parameters of cutting power, cutting forces and quality of the processed surface on the cutting regime and tool geometry. The proposed model proved to be adequate, as it describes the dependence of the examined machinability criteria on the selected impact factors with sufficient accuracy under the experimental conditions adopted in this research. In practice, this model can be applied to a corresponding real-world process of peripheral milling processing, as well as for varied input factors.

L'élevage des vins en barriques modifie profondément leur expression aromatique.L'étude par chromatographie en phase gazeuse et spectrométrie de masse permet d'identifier plusieurs substances volatiles appartenant à la fraction phénolique des arômes.Les vins rouges présentent naturellement une composition complexe en phénols volatils alors que celle des vins blancs est plus simple. L'élevage sous bois entraîne une augmentation notable des phénols déjà présents ainsi que l'apparition de molécules spécifiques au bois dechêne brûlé.L'interaction des levures et des bactéries avec le bois est mise en évidence.Les vins rouges se caractérisent par une présence parfois abondante d'éthyl phénols, les vins blancs qui ne subissent pas la fermentation malolactique s'en différencient par l'abondancede vinyl phénols.L'étude sensorielle de chaque substance permet de démontrer le rôle négligeable de certaines : furfural, méthyl-5-furfural, alcool furfurylique et le rôle exceptionnel joué par d'autres : cis et trans β-méthyl-γ-octalactone, vanilline et dans certains cas éthyl-4-phénol et éthyl-4-gaïacol.+++Wood storage of wines changes profondly their aromatic expression.Several volatile substances from wines and oak woods phenolic fraction of aroma are identified by gas chromatography and mass spectrometry. Wood storage increases natural phenols concentration. Simultaneously specific burned wood molecules appear.Yeast and bacterial interaction with wood is demonstrated. Ethyl phenols are characteristic of red wines and vinyl phenols of white wines without malolactic fermentation.The sensorial analysis of each substance demonstrates the negligible intervention in wine aroma of furfural, 5-methyl-furfural, and furfuryl alcohol, and the important participation of cis and trans β-methyl-γ-octalactone, vanilin 4-ethyl-phenol and 4-ethyl gaïacol.

The objective of this study was to investigate the suitability of oak (Ouercus robur L.) wood fibers from Turkey as a raw material for medium density fiberboard. In this study, some of the oak wood parts that are especially not suitable for other forest industries was utilized to produce fiberboards in laboratory environment. Test panels of varying densities (0.6, 0.7 and 0.8 g cm-3) were produced at 18 mm thickness using urea-formaldehyde adhesive. Mechanical, water resistance and dimensional stability properties of the test panels were determined according to Turkish standards. The results indicated that laboratory MDF panels produced using oak fibers resulted in mechanical properties that exceed (except panel type A) levels specified in the appropriate existing standards for the general propose fiberboards. © 2007 Asian Network for Scientific Information.

Infrared (IR) thermography is a widely applicable non-destructive testing (NDT) method for measuring the temperature distribution of an observed object surface. Through thermographic analysis, the IR radiation intensity of the electromagnetic spectrum is detected and recorded on the obtained thermograms. IR thermography has its advantages and disadvantages but it is a promising technique, which is easily applicable in the field and has no harmful impacts on the operator or equipment. In wood science and related fields, IR thermography can be applied in production quality control, monitoring of manufacturing equipment and plants for hydrothermal wood processing, wood properties characterization, defects detection (particularly holes, rot and drying cracks), heat flux in wood, and more [1]. During the thermographic analysis, temperature is not measured directly, but indirectly. Therefore, many factors can affect the accuracy of temperature measurement during quantitative thermography analysis, and one such factor is the emissivity of the observed object. Emissivity of the material is the ability of the surface to emit radiant energy expressed as the ratio of the radiant energy emitted by a surface to that emitted by a blackbody at the same temperature and under the same conditions. Emissivity depends on wavelength, temperature, object surface (opacity, roughness, orientation), the material from which the object is made, angle of measurement. Although important, those associated parameters often are not entirely specified along with the emissivity value in the literature. Therefore the experiment for establishing thermo-modified oak wood emissivity values within spectral range 7.5 – 13 μm was conducted. Also the emissivity of innate oak wood was determined for the comparison. For the experiment, an FLIR infrared system with the following characteristics was used. Imaging and optical data were as follows : field of view 25° x 25°, minimum focus distance 0.1 m, focal length 10 mm, instantaneous field of view (spatial resolution) 2.42 mrad, F-number 1.5, NETD 100 mK, image frequency 9 Hz. Detector type: FPA, uncooled microbolometer, with spectral range 7.5–13 μm (LWIR, ISO–MIR), IRR 180 x 180 pixels. Oak wood (Quercus robur L.) specimens used in the experiment were radial texture elements clear of defects, with approximately the same three ring width. There were 60 innate oak wood specimens and 60 thermo-modified oak wood specimens with the final dimensions 270 mm (length) by 65 mm (width) by 25 mm (thickness). Innate oak wood elements were kiln dried and then four sides planed. The moisture content of the specimens was 9 %. Thermo- modified wood elements were kiln dried, then thermally treated and afterwards four sides planed. The moisture content of the specimens was 5 %. The moisture content of specimens was determined according to EN 13183-1:2002/AC:2003 Moisture content of a piece of sawn timber – Part 1: Determination by oven dry method. A polyvinyl chloride material with known emissivity in long wavelength infrared (LWIR) spectral range was applied to the surface of all specimens. The emissivity of the polyvinyl chloride material was verified and the oak wood specimens were heated to 50 °C. During the experiment, the ambient characteristics were as follows: air temperature 21 °C, relative humidity 60 %, reflected apparent temperature 20.2 °C, the distance of oak wood specimens surface from the lens was 120 mm, angle of measurement in relation to the object normal was 15°, airflow and dotted reflections were inhibited. Emissivity values were determined via FLIR software with an area box tool with following dimensions 70×30 pixels. There was a significant difference in the results for innate and thermo- modified oak wood emissivity values (two-sample t(df) = -15.6, p = 0.00).

International audience; The evolution of both volatile and nonvolatile (ellagitannins) compounds extracted from oak wood chips while being macerated for 3 months in wine model solution with eight different commercial chips [Toasted LT (Light Toast), LT+ (Light plus Toast), MT (Medium Toast), MT+ (Medium plus Toast), HT (Heavy Toast), Noisette, Special) and un-toasted (UN)] was studied. Sensory analysis concerning vanilla, spicy, overall woody, astringency, bitterness and sweetness descriptors was conducted in parallel. A 2-month time is needed for the maximum extraction of ellagitannins and of furfural compound. Relating to other volatile compounds, their concentration increased progressively over time. Spicy, woody and vanilla aromas as well as sweetness perception increased during contact time with oak wood. Additionally to pyrolytic toasting stage, watering process during toasting influences significantly oak wood composition (lactones, vanillin guaiacol compounds and ellagitannins). Correlation analysis between chemical and sensory data demonstrated significant correlations between chemical and sensory parameters and provides some insight into the implication of volatile and nonvolatile composition on the final quality perception of astringency. A predictive model between astringency intensity and ellagitannins, furfural, guaiacol and methyl guaiacol contents was established. Ellagitannins levels explained 45 %, guaiacol and methyl guaiacol contents interpreted 13.20 and 8.86 %, respectively, whereas furfural levels justified 5.66 % of the total astringency variance.

http://www.sciencedirect.com/science/article/pii/S0963996913003736; International audience; Controlled and reproducible IR heat treatments were applied to oak wood surfaces in order to establish a depth-profiled picture of the extractability of volatile compounds, with particular emphasis on the impact of the initial water content. Headspace-solid phase microextraction-gas chromatography coupled to mass spectrometry (HS-SPME-GC-MS) has been used to compare the concentrations of six aroma compounds (vanillin, furfural, eugenol; guaiacol and cis- and trans-whisky lactones) in hydroalcoholic extracts of series of slices representative of the first 8 mm of the wood facing the IR source. Results have shown that although water is supposed to have a delaying effect with respect to the thermal degradation of wood macromolecules, it can favor heat transfers and thus promote higher-than-expected transient local temperatures in a soaked wood. Yet, distinct behaviors could be observed between thermally-generated compounds (vanillin and guaiacol), where adsorbed water seemed to prevent the thermal degradation of the parent macromolecule, and thermally-degraded compounds such as eugenol where the presence of water would balance the compound degradation through a more efficient extraction process of this biogenesis molecule. Furfural exhibited a more complex behavior since its production as a result of hemicellulose degradation was thermally-favored in the presence of adsorbed water. Finally, whatever the applied heat flux and regardless of the initial water content, temperatures experienced by the wood deeper than 4 mm, were lower than 160 °C, which meant that beyond that depth, the initial wood composition was unaffected.

This research paper reports on oven-dry oak wood (Quercus robur L.) emissivity value. Emissivity is very important property of material and it is used in infrared (IR) thermography. IR thermography is a non-destructive testing (NDT) method for measuring the temperature distribution of an observed object surface. It is applicable in a wide range of industrial and science applications. Currently in literature available emissivity values for wood differ from one another, and there is insufficient important complementary data. Often temperature, IR spectral waveband, wood specie, texture and other relevant wood information are not specified. Therefore the experiment for establishing oven-dry oak wood emissivity values within spectral range 7.5 – 13 μm (LWIR) was conducted, and the obtained results are presented in this research paper. Determined oak wood emissivity along with all important supporting data will facilitate the application of infrared thermography in wood related processes.

[EN] During red wine maturation in the presence of oak wood, reactions involving anthocyanins and ellagitannins might affect wine organoleptic properties such as color and astringency. In this work, the condensation reaction between myrtillin (delphinidin 3-O-glucoside) and vescalagin has been performed to determine the behavior of this anthocyanin in this kind of reaction and to assess the possible impact of such a reaction in wine color modulation. Two different hybrid pigments have been hemisynthetized and characterized by HPLC-DAD-MS and NMR spectroscopy. These pigments have been identified as 1-deoxyvescalagin-(1β→8)-myrtillin (major) and 1-deoxyvescalagin-(1β→6)-myrtillin (minor). The minor pigment could be formed both by the condensation reaction and by a regioisomerization process from the major pigment. Moreover, the chromatic properties of these pigments have been studied and compared to those of myrtillin. The hybrid pigments showed an important bathochromic shift (ca. 20 nm) in the maximum absorbance wavelength and lower molar absorption coefficients.

International audience; Flavours extracted from oak wood during barrel ageing contribute to the organoleptic character of wines and spirits. The aim of this work was to identify the glycosidic precursors of the key volatile compounds responsible for oak wood aroma. Oak extract is a very complex matrix and, furthermore, precursors are present in very small quantities. Preparative centrifugal partition chromatography (CPC) is a promising solution for purifying the oak extract. The solvent system was selected on the basis of the partition coefficient of glycosidase enzyme activity (Kca). Thanks to the efficacy of CPC separation, three glucoside gallates were subsequently isolated by HPLC chromatography. Vanillin-(6′-O-galloyl)-O-β-d-glucopyranoside, 3,4,5-trimethoxyphenyl-(6′-O-galloyl)-O-β-d-glucopyranoside, and (6R,9R)-3-oxo-α-ionol-9-O-(6′-O-galloyl)-β-glucopyranoside (macarangioside E) were isolated and identified. This was the first time that vanillin-(6′-O-galloyl)-O-β-d-glucopyranoside was identified and the first time that macarangioside E was isolated from oak wood. Heating macarangioside E resulted in the formation of megastigmatrienone, which has an aroma reminiscent of tobacco.

International audience; Some wood substances such as ellagitannins can be extracted during wine aging in oak barrels. The level of these hydrolyzable tannins in wine depends of some parameters of oak wood. Their impact on the organoleptic perception of red wine is poorly known. In our research, oak staves were classified in three different groups according to their level of ellagitannins estimated by NIBS (near infrared spectroscopy) online procedure (Oakscan). First, the ellagitannin level and composition were determine for each classified stave and an excellent correlation between the NIBS classification (low, medium and high potential level of ellagitannin) and the ellagitannin content estimated by HPLC-UV was found. Each different group of NIRS classified staves was then added to red wine during its aging in a stainless tank, and the extraction and evolution of the ellagitannins were monitored. A good correlation between the NIRS classification and the concentration of ellagitannins in red wine aging in contact with the classified staves was observed. The influence of levels of ellagitannins on the resulting wine perception was estimated by a trained judge's panel, and it reveals that the level of ellagitannins in wine has an impact on the roundness and amplitude of the red wine.

cited By 12; International audience; The aim of the study is to apply a plasma nitriding process to the 90CrMoV8 steel commonly employed in wood machining, and to determine its efficiency to improve both mechanical and electrochemical properties of the surface. Treatments were performed at a constant N2:H2 gas mixture and by varying the temperature and process duration. The structural and morphological properties of nitrided layers were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with EDS microanalyses. Surface hardening and hardness profiles were evaluated by micro hardness measurements. To simulate the wood machining conditions, electrochemical tests were carried out with an oak wood electrolyte with the purpose of understanding the effects of the nitriding treatment on the corrosion resistance of the tool in operation.X-ray diffraction analyses revealed the presence of both γ' (Fe4N) and ε (Fe2-3N) nitrides with a predominance of the ε phase. Moreover, α-Fe (110), γ' and ε diffraction peaks were shifted to lower angles suggesting the development of compressive stresses in the post nitrided steel. As a result, it was shown that nitriding allowed a significant hardening of steel with hardness values higher than 1200HV. The diffusion layers were always composed of an outer compound layer and a hardened bulk layer which thickness was half of the total diffusion layer one. No white layer was observed. Similarly, no traces of chromium nitrides were detected. The temperature seemed to be a parameter more influent than the process duration on the morphological properties of the nitrided layer, while it had no real influence on their crystallinity. Finally, the optimal nitriding conditions to obtain a thick and hard diffusion layer are 500°C for 10h.On the other hand, to verify the effect of these parameters on the corrosion resistance, potentiodynamic polarization tests were carried out in an original "wood juice" electrolyte. After corrosion, surface was then observed at the SEM scale. Electrochemical study indicated that the untreated steel behaved as a passive material. Although the very noble character of steel was somewhat mitigated and the corrosion propensity increased for nitrided steels, the passive-like nature of the modified surface was preserved. For the same optimized parameters as those deduced from the mechanical characterization (500 °C, 10. h), surface presented, in addition to a huge surface hardening, a high corrosion resistance. © 2011 Elsevier B.V.

The oenological quality of Spanish oak wood from Navarra (Quercus petraea Liebl.) in relation to French wood of recognised quality in cooperage has been evaluated. We have studied the effects of the Spanish wood on wine evolution during ageing, in regards to chromatic characteristics, polyphenols, and volatile compounds related to oak wood, in three different mono-varietal wines (cv. Tempranillo, cv. Cabernet Sauvignon and cv. Merlot) from the Origin Denomination Navarra. The results were compared with those obtained for the same wines aged in French oak barrels from central regions of France, obtained from five different French and Spanish cooperages. The wines aged in Spanish oak evolved in the same way as those aged in French. In general, at the end of the ageing process the differences in their chromatic and chemical characteristics were very small, although each wood type added special characteristics, the exact properties of which also depended on the grape variety. The Spanish oak wood (Q. petraea Liebl.) from Navarra has an oenological quality similar to French oak wood of the same species from Central region. © 2009 Elsevier Ltd. All rights reserved.

A miniaturised pressurised liquid technique has been applied to the extraction of volatile compounds present in oak wood samples used in making wine. The solvent extraction performed at high pressure and temperature has allowed the detection of a large number of compounds some of which present sensory and antioxidant properties. The effect of the main process variables on the efficiency of extraction has been studied: the composition of the extracted fraction depended mainly on the polarity of the solvent and the extraction temperature had a high influence on the extracted amount, while the effect of static extraction time and pressure were almost negligible. The highest recoveries were obtained for dichloromethane, for two static 10-min extraction cycles at 60 C. Among the solvent extraction techniques, miniaturised pressurised liquid extraction presents several advantages, such as the use of reduced amounts of both sample and solvent and high extraction efficiency., This work was financed by the Ministerio de Educacion y Ciencia under the project AGL2008-04913-CO2/ALI and by Comunidad de Madrid (ANALISYC Program, S-505/AGR-0312). M. Elena Alañónn thanks the Ministerio de Educacion y Ciencia for awarding a doctoral grant.

Pyrolytic oils produced from poultry litter differ in physico-chemical properties and the chemical composition. The litter is composed of manure and bedding material with traces of spilled feed and feathers. The type and amount of bedding material was varied to investigate its influence on the pyrolysis of layer manure. 400g of each feedstock: manure, wood (pine and oak), and mixtures of manure and wood in proportions (75:25 50:50, and 25:75 w/w %) respectively were subjected to fast pyrolysis at 450oC in a fluidized bed reactor. The total pyrolytic oil yield ranged from 43.3% to 64.5 wt%. The highest bio oil yield and the lowest char yield were obtained from oak wood. The manure oil had the highest HHV of 29.7 MJ/kg, the highest pH (5.89), the lowest density (1.14 g/cm3) and a relatively low viscosity of 130cSt. The oils had relatively high nitrogen content ranging from 5.88wt% to 1.36 wt%; low ash content (approximately

The evolution of almost 40 oak-related volatile compounds and the sensorial characteristics of red wines from four Spanish denominations of origin (DOs) (Bierzo, Toro, Ribera de Duero, and Rioja) during aging in barrels made of Rebollo oak wood, Quercus pyrenaica, were studied and compared to the same wines aged in American and French oak barrels. Each oak wood added unique and special characteristics to the wine, and in addition, each wine showed a different ability to extract the compounds, which result in these characteristics from the oak wood. In general, wines aged in Q. pyrenaica wood were characterized by high levels of eugenol, guaiacol, and other volatile phenols. In regards to compounds like cis-whiskylactone or maltol, the behavior of this wood is very similar to that of American oaks. When considering phenolic aldehydes and ketones, the levels of these compounds are intermediate between those of French and American woods and depend greatly on the type of wine. The type of oak, on the other hand, does not affect the chromatic characteristics of the wines. In sensory analysis, the biggest differences are found in the olfactory phase. Among the four DOs studied, wine aged in Q. pyrenaica presented the highest notes of wood, with more aromas of roasting, toasting, milky coffee, spices, or wine-wood interactions. The wines aged in barrels made of Q. pyrenaica wood were highly regarded, and preference was shown for them over those same wines when they had been aged in barrels of American or French oak. © 2008 American Chemical Society.

WOS: 000255516100015, PubMed: 19325775, In this study, screw and nail withdrawal resistance of fir (Abies nordmanniana), oak (Quercus robur L.) black pine (Pinus nigra Arnold) and Stone pine (Pinus pinea L.) wood were determined and compared. The data represent the testing of withdrawal resistance of three types of screws as smart, serrated and conventional and common nails. The specimens were prepared according to TS 6094 standards. The dimensions of the specimens were 5x5x15cm and for all of the directions. Moreover, the specimens were conditioned at ambient room temperature and 65+/-2% relative humidity. The screws and nails were installed according to ASTM-D 1761 standards. Nail dimensions were 2.5mm diameter and 50 mm length, conventional screws were 4x50mm, serrated screws were 4x45mm and smart screws were 4x50mm. Results show that the maximum screw withdrawal resistance value was found in Stone pine for the serrated screw. There were no significant differences between Stone pine and oak regarding screw withdrawal resistance values. Conventional screw yielded the maximum screw withdrawal resistance value in oak, followed by Stone pine, black pine and fir. Oak wood showed the maximum screw withdrawal resistance value for the smart screw, followed by Stone pine, black pine, and fir. Oak wood showed higher nail withdrawal resistances than softwood species. It was also determined that oak shows the maximum nail withdrawal resistance in all types. The nail withdrawal resistances at the longitudinal direction are lower with respect to radial and tangential directions.

Background and Aims: During ageing in oak barrels, wine undergoes changes because of the release of polyphenols and other molecules from wood. The aim of this study was to evaluate the influence of some oak wood-derived volatile compounds, ellagic acid and oak wood extracts on the levels of (+)-catechin, procyanidin B1 and malvidin-3-glucoside. Methods and Results: Phenolics and the oak wood derived volatile compounds studied were quantified by HPLC and by GC, respectively. Additionally, the new compounds formed in the solutions were characterised by their spectral properties. Ellagic acid and/or oak wood extracts slowed the decline in the levels of (+)-catechin and procyanidin B1. In contrast, the decrease in malvidin-3-glucoside was more pronounced in the presence of ellagic acid and oak wood chip extracts. Furfural slowed (+)-catechin degradation, while breakdown of malvidin-3-glucoside was slightly more pronounced in the presence of guaiacol, furfural, vanillin and eugenol. (+)-Catechin, procyanidin B1 and malvidin-3-glucoside did not significantly affect the rate of the degradation of ellagitannins during the storage time studied. Finally, new HPLC peaks were detected in the solutions containing (+)-catechin and ellagic acid, as well as with malvidin-3-glucoside with ellagic acid and oak wood extract. Conclusions: Malvidin 3-glucoside and (+)-catechin and procyanidin B1 presented distinct behaviours during time in the presence of volatile and non-volatile compounds from oak wood. Significance of the Study: This work points out the importance of oak wood components in the degradation of anthocyanins and tannins, as well as the reactions that occur during the ageing of red wine

Background and Aims: During ageing in oak barrels, wine undergoes changes because of the release of polyphenols and other molecules from wood. The aim of this study was to evaluate the influence of some oak wood-derived volatile compounds, ellagic acid and oak wood extracts on the levels of (+)-catechin, procyanidin B1 and malvidin-3-glucoside. Methods and Results: Phenolics and the oak wood derived volatile compounds studied were quantified by HPLC and by GC, respectively. Additionally, the new compounds formed in the solutions were characterised by their spectral properties. Ellagic acid and/or oak wood extracts slowed the decline in the levels of (+)-catechin and procyanidin B1. In contrast, the decrease in malvidin-3-glucoside was more pronounced in the presence of ellagic acid and oak wood chip extracts. Furfural slowed (+)-catechin degradation, while breakdown of malvidin-3-glucoside was slightly more pronounced in the presence of guaiacol, furfural, vanillin and eugenol. (+)-Catechin, procyanidin B1 and malvidin-3-glucoside did not significantly affect the rate of the degradation of ellagitannins during the storage time studied. Finally, new HPLC peaks were detected in the solutions containing (+)-catechin and ellagic acid, as well as with malvidin-3-glucoside with ellagic acid and oak wood extract. Conclusions: Malvidin 3-glucoside and (+)-catechin and procyanidin B1 presented distinct behaviours during time in the presence of volatile and non-volatile compounds from oak wood. Significance of the Study: This work points out the importance of oak wood components in the degradation of anthocyanins and tannins, as well as the reactions that occur during the ageing of red wine

The effect of various oak wood seasoning methods, natural seasoning in open air, artificial seasoning in a kiln, and a mixed method that combines open air and kiln drying, on the chemical composition in American (Quercus alba) and French (Quercus petraea) oak was studied. The results confirm the evolution of ellagitannins in wood, low molecular polyphenols, and volatile compounds in relation to oak species and seasoning method. Natural seasoning in open air can be considered a superior method to mixed or artificial drying for wood seasoning in cooperage. It was more effective in reducing the excess of ellagitannins, especially in French oak wood. Moreover, the evolution of wood volatile compounds was more positive in the natural seasoning than mixed or artificial drying, since it led to woods with higher aromatic potential (larger concentrations of compounds such as volatile phenols, phenolic aldehydes, furanic compounds, and cis- and trans-β-methyl-γ-octalactones) than mixed or artificial methods. However, the three seasoning methods showed similar effectiveness regarding the desired reduction of off-flavors compounds. © 2008 American Chemical Society.

Patterns of spore dispersal of the fungal pathogen Apiognomonia quercina and its anamorph Discula quercina were investigated over two consecutive growing seasons in a natural mixed stand of Quercus cerris and Q. pubescens trees located in a inland area of Tuscany, at an altitude of 400 m a.s.l. To measure spore dispersal, a transect was laid out in the stand to serve as an inoculum source. The rate of inoculum dispersal (conidia and ascospores) was quantifi ed by means of spore traps positioned at 10, 100, 500 and 1000 m from the southern end of the transect. The disease gradient was also assessed by determining the disease incidence on selected trees at the same distances from the transect. The amount of inoculum detected decreased steeply with the distance from the transect. Disease incidence was inversely correlated with the disease gradient, i.e. with the distance from the inoculum source, and it was much higher at the shorter distances. The level of spore dispersal was related to both the distance from the infection foci and the sporulation time. The experimental approach constituted a valid means for describing and understanding the dynamics of windborne diseases in forests.

The study have dimostrated the evolution of c-glucisidic ellagitannins during wine aging occurred in presence of oak wood. HPLC-MS was used to characterizise these compounds. After 24 days of maceration with oak, the wine showed a similar concentration of the same wine ageing for 1 year in barrique.

In this paper, the changes in the composition of a red wine obtained from Tempranillo grapes (Vitis vinifera L.), stored from 12 to 24 months in bottles were studied. The wine was previously aging for 21 months in barrels made of Spanish oak wood (Quercus spp.). The changes of chromatic data, global polyphenolic families assessment (polyphenols, catechins, proanthocyanidins and anthocyanins) and individually polyphenols by HPLC during their storage time in bottles were studied and compared with these of the same wine aged in barrels made of French oak and American oak and stored in bottle for 24 months. Samples of wines obtained after 12 months in bottle were also compared with those after 24 months. The stepwise discriminant analysis with data of chromatic parameters and global polyphenolic families indicates that the wines aged in Spanish and French oak wood barrels, after 24 months stored in bottle, have similar characteristics, but they are significantly different to those of wines aged in barrels made of American oak wood. Regarding the analysis of individually non-anthocyanic polyphenols, discriminant analysis shows that wines stored for 24 months in bottle, aged in barrels made of Spanish, French and American oak woods, show overlapping results, while those from wines after 12 months in bottle are more dispersed. The discriminant analysis carried out on anthocyanidin concentrations of wines stored 24 months in bottles has shown three groups according the kind of wood used, indicating that wines aged in Spanish and French oak barrels are much more similar in anthocyanidin concentrations than those aged in the American barrels. © Springer-Verlag 2007.

The need for new sources of quality wood supply for cooperage has led to looking into the possibility of utilizing Quercus pyrenaica Wild. oak, a species native to the Iberian peninsula, as an alternative to other European (Quercus robur and Qurecus petraea) and American (Quercus alba) oaks. The low molecular weight phenolic composition, ellagitannins, and volatile compounds (including a wide range of compound families such as volatile phenols, furanic compounds, lactones, phenyl ketones, other lignin-derived compounds, and volatile compounds related to off-flavors) of green heartwood from Spanish forest regions were studied by HPLC and GC, in order to know its enological characteristics. The chemical composition of Q. pyrenaica is similar to that of other species commonly used in cooperage to make barrels, showing only quantitative differences that were more significant with respect to American than to French species. The four provenance regions studied showed similar chemical composition, with high variability among individuals, often higher than the variability among regions of provenance, but in line with that described in other European and American oak woods. Therefore, this species must be considered to be suitable for aging wine. © 2006 American Chemical Society.

Species effects and ecological conditions on ten heartwood ellagitannins (vescalin, castalin, roburins A-E, grandinin, vescalagin and castalagin)and ellagic acid were investigated in a 100 years old stand of 5 ha located in western France (La Petite Charnie State Forest, Sarthe). The sample included a total of 286 trees (118 sessile oaks, 158 pedunculate oaks and 10 individuals with an intermediate morphology) located in three ecological zones (plateau, slope, small valley). The main factor influencing oak extractives level was botanical species. The ecological zone effect appears negligible. Pedunculate oak is generally richer in ellagitannins (48.4 mg/g against 34.4 for sessile oak), although a clear boundary between the two species cannot be established. Ellagitannin content was found to be correlated with ring width for pedunculate oak and not for sessile oak. The vescalagin/castalagin ratios differed between the two species (0.69 for Quercus robur against 0.53 for Quercus petraea). The distribution of ellagitannin contents is not strongly structured spatially, Les effets de l’espèce et des conditions écologiques sur le contenu du duramen externe de dix ellagitanins (vescaline, castaline, roburines A à E, grandinine, vescalagine, castalagine) et de l’acide ellagique ont été étudiés dans un peuplement équien (100 ans) de chêne d’une surface de 5 ha située dans l’ouest de la France (forêt domaniale de La Petite Charnie, Sarthe). L’échantillon total se composait de 286 arbres (118 chênes sessiles, 158 chênes pédonculés et 10 chênes intermédiaires) répartis en mélange dans trois zones écologiques du peuplement (plateau, pente et fond de vallon). Le facteur principal qui influence la teneur en ellagitanin est l’espèce botanique, alors que le facteur « zone » est négligeable dans les conditions expérimentales considérées. Le bois de chêne pédonculé est plus riche en ellagitanins que celui du chêne sessile (48,4 mg/g pour le chêne pédonculé ; 34,4 mg/g pour le chêne sessile), mais une distinction claire entre les deux espèces ne peut être établie. Une corrélation entre la teneur en ellagitanin et la largeur de cerne est observée pour le chêne pédonculé à la différence du cas du chêne sessile. Le rapport vescalagine/castalagine est plus élevé pour le chêne pédonculé que pour le chêne sessile (0,69 et 0,53). La structuration spatiale est faible

The mixed oak (Quercus robur) and ash (Fraxinus oxycarpa)wood located near the town of Motovun is a well-known white truffle - the Tuber magnatum Pico fungus species - producing area in Istria. Motovun forest covers a 900-ha are in the fluvial plain of River Mirna, which flows into the Adriatic Sea in a hilly landscape originated by a sedimentary sequence of a Triassic-Eocene carbonatic platform and Eocene-Oligocene Flysch turbidities, the quite high erodibility of which has originated very thin soils on slopes and thick undifferentaited alluvia in valley bottoms. White truffle production has been decreasing in the last 10 years and a study was specifically performed in an attempt to explain it. The study area was subdivided into productive and unproductive sub-areas on the basis of the 1:50.000 soil map of Croatia and of the experience of truffle searchers. Sampling locations with an approximate density of 1 observation every 10 ha were selected according to a stratified random sampling design. The morphological features of their soil were observed in 100-cm deep augerings, whereas chemical-physical properties were determined in undisturbed samples collected in the 0-10 cm layer, where carpophores are usually found. Unproductive soils on slopes - Calcaric Regosols, according to FAO classification - were compared to productive and unproductive Gleysols of the valley bottom, the former being drier, thinner and more developed than the latter. T. magnatum carpophores are not found all over the fluvial plain and Motovun forest was further subdivided into productive, unproductive and occasionally productive areas. All soils of the valley bottom were thick and continuously rejuvenated by the frequent deposition of fine sediments from slopes, but only unproductive ones were characterized by water saturation in some periods of the year. The soil comparison proved the need of white truffle for an alkaline, moist, very well drained and aerated soil environment. Moreover, soils suitable for white truffle should be neither too dry nor too moist. In Motovun forest, instead, the decrease of production has been taking place in combination with public works that have modified the hydraulic equilibrium of the valley bottm in the last 40 years, causing an overall drying of the forest soil.

International audience; Species effects and ecological conditions on ten heartwood ellagitannins (vescalin, castalin, roburins A-E, grandinin, vescalagin and castalagin)and ellagic acid were investigated in a 100 years old stand of 5 ha located in western France (La Petite Charnie State Forest, Sarthe). The sample included a total of 286 trees (118 sessile oaks, 158 pedunculate oaks and 10 individuals with an intermediate morphology) located in three ecological zones (plateau, slope, small valley). The main factor influencing oak extractives level was botanical species. The ecological zone effect appears negligible. Pedunculate oak is generally richer in ellagitannins (48.4 mg/g against 34.4 for sessile oak), although a clear boundary between the two species cannot be established. Ellagitannin content was found to be correlated with ring width for pedunculate oak and not for sessile oak. The vescalagin/castalagin ratios differed between the two species (0.69 for Quercus robur against 0.53 for Quercus petraea). The distribution of ellagitannin contents is not strongly structured spatially; Les effets de l’espèce et des conditions écologiques sur le contenu du duramen externe de dix ellagitanins (vescaline, castaline, roburines A à E, grandinine, vescalagine, castalagine) et de l’acide ellagique ont été étudiés dans un peuplement équien (100 ans) de chêne d’une surface de 5 ha située dans l’ouest de la France (forêt domaniale de La Petite Charnie, Sarthe). L’échantillon total se composait de 286 arbres (118 chênes sessiles, 158 chênes pédonculés et 10 chênes intermédiaires) répartis en mélange dans trois zones écologiques du peuplement (plateau, pente et fond de vallon). Le facteur principal qui influence la teneur en ellagitanin est l’espèce botanique, alors que le facteur « zone » est négligeable dans les conditions expérimentales considérées. Le bois de chêne pédonculé est plus riche en ellagitanins que celui du chêne sessile (48,4 mg/g pour le chêne pédonculé ; 34,4 mg/g pour le chêne sessile), mais une distinction claire entre les deux espèces ne peut être établie. Une corrélation entre la teneur en ellagitanin et la largeur de cerne est observée pour le chêne pédonculé à la différence du cas du chêne sessile. Le rapport vescalagine/castalagine est plus élevé pour le chêne pédonculé que pour le chêne sessile (0,69 et 0,53). La structuration spatiale est faible

A red Rioja wine aged for 21 months in barrels made of Spanish oak wood (Quercus spp.), was stored in bottles for 24 months at wine cellar. The evolution of some volatile compounds during their storage time in bottles was studied and compared with the evolution of the same wine, but aged in barrels made of French oak (Q. robur, Q. petraea) and American oak (Q. alba). Although the volatile composition of wine underwent an evolution during bottle aging, this was carried out in such a way that the most important characteristics spread into wine from wood, remained until the end of bottle aging, or at least, for the 24 months of our research. Therefore, wines with different characteristics were obtained from the same wine, after 21 months of aging in barrels and 24 months of aging in bottle, depending on the kind of wood used in oxidative aging. © 2005 Elsevier B.V. All rights reserved.

Dans le cadre de la vente en regie, les bois sont repartis en classes de qualite et de diametre dont le croisement definit une categorie de produit. Cette information a ete utilisee pour modeliser le prix du bois de Chene. Le modele propose est compose de trois parties. La premiere partie estime la valeur des differentes categories au sein du lot. La seconde partie est une correction liee a l'heterogeneite mettant en evidence qu'un lot regroupant plusieurs categories ne peut etre considere comme la simple reunion de lots homogenes de ces categories. Enfin, la derniere partie permet une estimation de la variance, donc de la precision de l'estimation du prix a l'echelle du lot. La necessite de prendre en compte l'heterogeneite des lots nous amene a analyser les consequences de celle-ci sur les prix et a proposer une reflexion sur la constitution ideale des lots.