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Forests are threatened globally by increased recurrence and intensity of hot droughts. Functionally close coexisting species may exhibit differences in drought vulnerability large enough to cause niche differentiation and affect forest dynamics. The effect of rising atmospheric [CO2], which could partly alleviate the negative effects of drought, may also differ between species. We analysed functional plasticity in seedlings of two taxonomically close pine species (Pinus pinaster Ait., Pinus pinea L.) under different [CO2] and water stress levels. The multidimensional functional trait variability was more influenced by water stress (preferentially xylem traits) and [CO2] (mostly leaf traits) than by differences between species. However, we observed differences between species in the strategies followed to coordinate their hydraulic and structural traits under stress. Leaf 13C discrimination decreased with water stress and increased under elevated [CO2]. Under water stress both species increased their sapwood area to leaf area ratios, tracheid density and xylem cavitation, whereas they reduced tracheid lumen area and xylem conductivity. Pinus pinea was more anisohydric than P. pinaster. Pinus pinaster produced larger conduits under well-watered conditions than P. pinea. Pinus pinea was more tolerant to water stress and more resistant to xylem cavitation under low water potentials. The higher xylem plasticity in P. pinea, particularly in tracheid lumen area, expressed a higher capacity of acclimation to water stress than P. pinaster. In contrast, P. pinaster coped with water stress comparatively more by increasing plasticity of leaf hydraulic traits. Despite the small differences observed in the functional response to water stress and drought tolerance between species, these interspecific differences agreed with ongoing substitution of P. pinaster by P. pinea in forests where both species co-occur. Increased [CO2] had little effect on the species-specific relative perf

Intraspecific grafting with selected scions and rootstocks was used to study drought tolerance in the recalcitrant Mediterranean conifer P. pinaster. Conifers store different terpene types in needles, stems and roots, which can be modified by drought, but most studies have focused on a single organ and over selected terpenes which limits understanding of the overall plant response. In this work, terpene profile (160 components among mono-, sesqui-, di-terpenes and resin acids) as well as eco-physiological traits were assessed in needles, roots, and scion and rootstock stems to analyze the drought sensibility of scions and rootstocks on grafted P. pinaster trees. We used two scions from wet (Galicia) and dry (Oria) provenances grafted onto rootstocks showing differences in the efficiency of water use, grown under two different water regimes, well-watered and water stressed. Constitutively, organs showed clearly different qualitative and quantitative terpene profiles, such as a long-term optimized resources allocation, being neutral and acid diterpenes those more discriminant. Environmental factors may selectively affect the regulation of diterpene biosynthesis in needles, since scion provenances determined the variation of their profiles, mainly regarding again neutral and acid diterpenes. Different scion-conferred terpene phenotypes were observed in each organ, having a relevant role isoabienol content. Drought triggered needle/root resin acids redistribution, which may provide higher protection to roots, correlated to the effective water stress endured by plants. Drought sensitivity of scion-rootstock combinations determined the intensity of drought-triggered changes in terpene levels in all organs, suggesting that chemical defense and drought tolerance are somehow interconnected.

Impact of drought under enriched CO2 atmosphere on ecophysiological and leaf metabolic response of the sub-mediterranean Q. pyrenaica oak was studied. Seedlings growing in climate chamber were submitted to moderate drought (WS) and well-watered (WW) under ambient ([CO2]amb =400 ppm) or CO2 enriched atmosphere ([CO2]enr =800 ppm). The moderate drought endured by seedlings brought about a decrease in leaf gas exchange. However, net photosynthesis (Anet) was highly stimulated for plants at [CO2]enr. There was a decrease of the stomatal conductance to water vapour (gwv) in response to drought, and a subtle trend to be lower under [CO2]enr. The consequence of these changes was an important increase in the intrinsic leaf water use efficiency (WUEi). The electron transport rate (ETR) was almost a 20 percent higher in plants at [CO2]enr regardless drought endured by seedlings. The ETR/Anet was lower under [CO2]enr, pointing to a high capacity to maintain sinks for the uptake of extra carbon in the atmosphere. Impact of drought on the leaf metabolome, as a whole, was more evident than that from [CO2] enrichment of the atmosphere. Changes in pool of non-structural carbohydrates were observed mainly as a consequence of water deficit including increases of fructose, glucose, and proto-quercitol. Most of the metabolites affected by drought back up to levels of non-stressed seedlings after rewetting (recovery phase). It can be concluded that carbon uptake was stimulated by [CO2]enr, even under the stomatal closure that accompanied moderate drought. In the last, there was a positive effect in intrinsic water use efficiency (WUEi), which was much more improved under [CO2]enr. Leaf metabolome was little responsible and some few metabolites changed mainly in response to drought, with little differences between [CO2] growth conditions.

Rising atmospheric CO2 concentrations ([CO2]) together with water deficit can influence ecological interactions of trees through an array of chemically driven changes in plant leaves. In four drought stressed Pinus pinaster genotypes, grown under two levels of atmospheric [CO2] (ambient (aCO2) and enriched (eCO2)) the metabolome of adult and juvenile needles was analyzed to know if the metabolic responses to this environmental situation could be genotype-dependent and vary according to the stage of needle ontogeny. Drought had the highest incidence, followed by needle ontogeny, being lower the eCO2 effect. The eCO2 reduced, eliminated or countered the 50 (adult needles) - 44% (juvenile) of the drought-induced changes, suggesting that CO2-enriched plants could perceived less oxidative stress under drought, and proving that together, these two abiotic factors triggered a metabolic response different from that under single factors. Genotype drought tolerance and ontogenetic stage determined the level of metabolite accumulation and the plasticity to eCO2 under drought, which was mainly reflected in antioxidant levels and tree chemical defense. At re-watering, previously water stressed plants showed both, reduced C and N metabolism, and a "drought memory effect", favoring antioxidants and osmolyte storage. This effect showed variations regarding genotype drought-tolerance, needle ontogeny and [CO2], with remarkable contribution of terpenoids. Chemical defense and drought tolerance were somehow linked, increasing chemical defense during recovery in the most drought-sensitive individuals. The better adaptation of trees to drought under eCO2, as well as their ability to recover better from water stress, are essential for the survival of forest trees.

[EN] The use of new oak barrels and the demand for oak wood in oenology is increasing. Thus, it is necessary to search for new wood sources to supply the current demand in cooperage. The aim of this work was to study the composition of ellagitannins and low molecular weight phenolic compounds (LMWP) by HPLC-DAD of green wood Quercus humboldtii Bonpl. (Colombian), compared to the species typically used in cooperage: Quercus sessiliflora Salisb. (French and Romanian) and Quercus alba L. (USA). In Colombian oak wood, the same LMWP and ellagitannins as in the traditional species were identified. The most abundant LMWP was ellagic acid, and its concentration was lower in Q. humboldtii and Q. alba than in Q. sessiliflora, so these two presented a lower content of phenolic acids. As regards phenolic aldehydes, Colombian oak wood only showed significant differences in the content of coniferyl and sinapic aldehydes in relation to French oak. Finally, the total ellagitannin content of Q. humboldtii was lower than that of European oaks and similar to that of American oak (Q. alba). None of the ellagitannins studied presented significant differences compared to Q. alba. Therefore, Q. humboldtii wood was more similar in terms of phenolic composition to Q. alba than to Q. sessiliflora., [PT] O uso de novos barris de carvalho e a procura de madeira de carvalho em enologia estão aumentando. Assim, torna-se necessária a investigação de novas fontes de madeira para satisfazer a atual procura pela tanoaria. O objetivo deste trabalho foi estudar a composição de taninos elágicos e compostos fenólicos de massa molecular baixa (LMWP) por HPLC-DAD de madeiras verdes de Quercus humboldtii Bonpl. (colombiano), em comparação com espécies tipicamente usadas em tanoaria: Quercus sessiliflora Salisb. (francês e romeno) e Quercus alba L. (EUA). Na madeira de carvalho da Colômbia, foram identificados os mesmos LMWP e taninos elágicos do que nas espécies tradicionais. O LMWP mais abundante foi o ácido elágico, e sua concentração foi menor em Q. humboldtii e Q. alba do que em Q. sessiliflora, portanto estas duas madeiras apresentaram menor teor de ácidos fenólicos. Em relação aos aldeídos fenólicos, a madeira de carvalho colombiano mostrou diferenças significativas no teor de aldeídos coniferílico e sinápico em relação ao carvalho francês. Finalmente, o conteúdo total de taninos elágicos de Q. humboldtii foi inferior ao dos carvalhos europeus e semelhante ao do carvalho americano (Q. alba). Nenhum dos taninos elágicos estudados apresentou diferenças significativas relativamente a Q. alba. Assim, a composição fenólica da madeira de Q. humboldtii assemelha-se mais à da madeira de Q. alba do que à de Q. sessiliflora.

Pinus pimaster Aiton displays marked heteroblasty during its vegetative phase, showing complex interactions between developmental processes and environmental adaptation, with a patent differentiation in functional performance according to leaf type resulting from heteroblasty. In this work, untargeted quantitative metabolic profiling in adult and juvenile needles of four water-deficit stressed P. pinaster genotypes was investigated to know if metabolic responses to drought are genotype-dependent and vary according to the stage of needle ontogeny. Among the changes in metabolome, it highlights the increase of osmotically active substances, as well as the overproduction of antioxidant compounds by up-regulating ascorbate, shikimate/phenylalanine and phenylpropanoid metabolic pathways. Moreover, significant inter-clonal quantitative variations were also found at different levels, in both primary and secondary metabolism pathways, although terpenoids and specially flavonoids showed the highest significance. A surprising result was the ontogenetic changes in metabolic profiles. Juvenile needles contain significant higher levels of UV screener and antioxidant flavonoids. The level of drought tolerance of a genotype and the ontogenetic stage were important factors in determining the drought-induced level of flavonoid increase in needles of a given genotype. Regarding terpenoids, the significant drought-induced accumulation of neutral diterpenes in juvenile needles, and mono- and sesquiterpenes in adults, was genotype dependent regardless its degree of drought tolerance. These results point to flavonoids as very versatile metabolites in maritime pine needle, acting like important compounds modulating not only drought acclimation but also changes in needle metabolism associated with developmental processes such as heteroblasty. © 2017 Elsevier B.V.

The use of new oak barrels and the demand for oak wood in oenology is increasing. Thus, it is necessary to search for new wood sources to supply the current demand in cooperage. The aim of this work was to study the composition of ellagitannins and low molecular weight phenolic compounds (LMWP) by HPLC-DAD of green wood Quercus humboldtii Bonpl. (Colombian), compared to the species typically used in cooperage Quercus sessiliflora Salisb. (French and Romanian) and Quercus alba L. (USA). In Colombian oak wood, the same LMWP and ellagitannins as in the traditional species were identified. The most abundant LMWP was ellagic acid, and its concentration was lower in Q. humboldtii and Q. alba than in Q. sessiliflora, so these two presented a lower content of phenolic acids. As regards phenolic aldehydes, Colombian oak wood only showed significant differences in the content of coniferyl and sinapic aldehydes in relation to French oak. Finally, the total ellagitannin content of Q. humboldtii was lower than that of European oaks and similar to that of American oak (Q. alba). None of the ellagitannins studied presented significant differences compared to Q. alba. Therefore, Q. humboldtii wood was more similar in terms of phenolic composition to Q. alba than to Q. sessiliflora.

Drought is an important driver of plant survival, growth, and distribution. Water deficit affects different pathways of metabolism, depending on plant organ. While previous studies have mainly focused on the metabolic drought response of a single organ, analysis of metabolic differences between organs is essential to achieve an integrated understanding of the whole plant response. In this work, untargeted metabolic profiling was used to examine the response of roots, stems, adult and juvenile needles from Pinus pinaster Ait. full-sib individuals, subjected to a moderate and long lasting drought period. Cyclitols content showed a significant alteration, in response to drought in all organs examined, but other metabolites increased or decreased differentially depending on the analyzed organ. While a high number of flavonoids were only detected in aerial organs, an induction of the glutathione pathway was mainly detected in roots. This result may reflect different antioxidant mechanisms activated in aerial organs and roots. Metabolic changes were more remarkable in roots than in the other organs, highlighting its prominent role in the response to water stress. Significant changes in flavonoids and ascorbate metabolism were also observed between adult and juvenile needles, consistent with previously proven differential functional responses between the two developmental stages. Genetic polymorphisms in candidate genes coding for a Myb1 transcription factor and a malate dehydrogenase (EC 1.1.1.37) were associated with different concentration of phenylalanine, phenylpropanoids and malate, respectively. The results obtained will support further research on metabolites and genes potentially involved in functional mechanisms related to drought tolerance in trees. © 2016 Elsevier Masson SAS.

This study develops a new method to produce more complex wines by means of an indirect diffusion of wood aromas from yeast cell-walls. An exogenous lyophilized biomass was macerated with an ethanol wood extract solution and subsequently dried. Different times were used for the adsorption of polyphenols and volatile compounds to the yeast cell-walls. © 2014 Elsevier Ltd. All rights reserved.

Introduction - Fagus sylvatica L. is one of the most widely distributed broad-leaved tree species in central and western Europe, important to the forest sector and an accurate biomarker of climate change. Objective - To profile the beech leaf metabolome for future studies in order to investigate deeper into the characterisation of its metabolic response. Methods - Leaf extracts were analysed using LC-MS by electrospray ionisation in negative mode from m/z 100-1700 and GC-MS by electron ionisation in scan mode from m/z 35-800. Results - The LC-MS profile resulted in 56 compounds, of which 43 were identified and/or structurally characterised, including hydroxycinnamic acid derivatives, flavan-3-ols and proanthocyanidins, and flavonols. From a second analysis based on GC-MS, a total of 111 compounds were identified, including carbohydrates, polyalcohols, amino acids, organic acids, fatty acids, phenolic compounds, terpenoids, sterols and other related compounds. Many of the compounds identified were primary metabolites involved in major plant metabolic pathways, however, some secondary metabolites were also detected. Some of them play roles as tolerance-response osmoregulators and osmoprotectors in abiotic stress, or as anti-oxidants that reduce the effect of reactive oxygen species and promote many protective functions in plants. Conclusions - This study provides a broad and relevant insight into the metabolic status of F. sylvatica leaves, and serves as a base for future studies on physiological and molecular mechanisms involved in biotic or abiotic stress. Copyright © 2014 John Wiley & Sons, Ltd.

The nonanthocyanic phenolic composition of four red wines, one white, and one rosé aged using barrels and chips of cherry, chestnut, false acacia, ash and oak wood was studied by LC-DAD-ESI/MS, to identify the phenolic compounds that woods other than oak contribute to wines, and if some of them can be used as chemical markers of ageing with them. A total of 68 nonanthocyanic phenolic compounds were identified, 15 found only in wines aged with acacia wood, 6 with cherry wood, and 1 with chestnut wood. Thus, the nonanthocyanic phenolic profile could be a useful tool to identify wines aged in contact with these woods. In addition, some differences in the nonanthocyanic phenolic composition of wines were detected related to both the levels of compounds provided by each wood species and the different evolution of flavonols and flavanols in wines during ageing in barrels or in contact with chips. © 2013 Elsevier Ltd.

Variation of monoterpene, sesquiterpene, neutral diterpene, and fatty and resin acid composition was determined in adult needles of two chemotypes of Pinus pinaster Ait.;sampled in two different seasons summer and winter. Throughout the year, the terpenic and fatty acid composition of adult needles of P. pinaster showed a seasonal variation, both at individual and at global level. These seasonal variations in distribution pattern were not produced in the same way in the needles of the two chemotypes studied. Therefore, we consider that secondary metabolism compounds do not present the same sensitivity to environmental conditions, and genetically different trees have different responses to these environmental conditions. © 2013 Springer-Verlag Wien.

The wood-related volatile profile of wines aged in cherry, acacia, ash, chestnut and oak wood barrels was studied by GC-MS, and could be a useful tool to identify the wood specie used. Thus, 2,4-dihydroxybenzaldehyde in wines aged in acacia barrels, and ethyl-2-benzoate in cherry barrels could be used as chemical markers of these wood species, for authenticity purposes. Also, the quantitative differences obtained in the volatile profiles allow a good classification of all wines regarding wood species of barrels, during all aging time, and they contributed with different intensities to aromatic and gustative characteristics of aged wines. Wines aged in oak were the best valuated during all aging time, but the differences were not always significant. The lowest scores were assigned to wines aged in cherry barrels from 6 months of aging, so this wood could be more suitable in short aging times. © 2013 Elsevier Ltd. All rights reserved.

The aroma profiles of six different types of wood were evaluated by gas chromatography-olfactometry (GC-O) in order to examine their possible use as materials for making wooden barrels. The study revealed the presence of 46 odorants. Only one could not be identified, although information about its retention indices was determined in both DB-WAX and VF-5MS columns. It can be said that some of these odorants constitute the base of the aroma of these types of wood (sotolon, cis-2-nonenal, furaneol, maltol, 2-methyl-3-furanthiol, guaiacol and trans-2-nonenal). All the odorants were scored with a modified frequency higher than 55% in all the wood samples. The study revealed useful information about those compounds responsible for the greatest aromatic differences between the six wood extracts. Cyclotene, 2-acetyl-3-methylpyrazine, cis-whiskylactone and 2-acetylthiazole are some of the most discriminant compounds found among the samples. Finally, the study demonstrated that GC-O analysis has been able to detect some of these discriminant odorants for the first time, as was the case with 2-acetyl-3-methylpyrazine and 2-acetylthiazole present in acacia wood. Another new finding was that GC-O analysis allowed us to detect cis-whiskylactone in chestnut wood. Therefore, information provided by GC-O must be always taken into account. © 2013 Elsevier Ltd.

Polyphenolic composition of two Syrah wines aged during 6 or 12 months in medium toasting acacia and oak 225. L barrels was studied by LC-DAD-ESI/MS. A total of 43 nonanthocyanic phenolic compounds were found in all wines, and other 15 compounds only in the wines from acacia barrels. Thus, the nonanthocyanic phenolic profile could be a useful tool to identify the wines aged in acacia barrels. Among all of them the dihydrorobinetin highlights because of its high levels, but also robinetin, 2,4-dihydroxybenzaldehyde, a tetrahydroxydihydroflavonol, fustin, butin, a trihydroxymethoxydihydroflavonol and 2,4-dihydroxybenzoic acid were detected at appreciable levels in wines during aging in acacia barrels, and could be used as phenolic markers for authenticity purposes. Although longer contact time with acacia wood mean higher concentrations of phenolic markers found in wines, the identification of these wines will also be easy after short aging times due the high levels reached by these compounds, even after only 2 months of aging. © 2012 Elsevier B.V.

The phenolic composition of heartwood extracts from Fraxinus excelsior L.;F. americana L.;both before and after toasting in cooperage, was studied using LC-DAD/ESI-MS/MS. Low-molecular weight (LMW) phenolic compounds, secoiridoids, phenylethanoid glycosides, dilignols and oligolignols compounds were detected, and 48 were identified, or tentatively characterized, on the basis of their retention time, UV/Vis and MS spectra, and MS fragmentation patterns. Some LMW phenolic compounds like protocatechuic acid and aldehyde, hydroxytyrosol and tyrosol, were unlike to those for oak wood, while ellagic and gallic acid were not found. The toasting of wood resulted in a progressive increase in lignin degradation products with regard to toasting intensity. The levels of some of these compounds in medium-toasted ash woods were much higher than those normally detected in toasted oak, highlighting vanillin levels, thus a more pronounced vanilla character can be expected when using toasted ash wood in the aging wines. Moreover, in seasoned wood, we found a great variety of phenolic compounds which had not been found in oak wood, especially oleuropein, ligstroside and olivil, along with verbascoside and isoverbascoside in F. excelsior, and oleoside in F. americana. Toasting mainly provoked their degradation, thus in medium-toasted wood, only four of them were detected. This resulted in a minor differentiation between toasted ash and oak woods. The absence of tannins in ash wood, which are very important in oak wood, is another peculiar characteristic that should be taken into account when considering its use in cooperage. Copyright © 2012 John Wiley & Sons, Ltd.

The existence of two chemotypes of Pinus pinaster, on the basis of the chemical composition of the resin acids in their needles, is known. An investigation was performed on 54 samples of needles of Spanish Pinus pinaster to study the differences between these chemotypes on the basis of monoterpene, sesquiterpene, neutral diterpene, fatty acid, and resin acid composition. One-hundred and twelve compounds were identified by GC-FID and GC-MS. Statistical analysis of the results established the existence of two groups or chemotypes, in the ratio of 51. In one chemotype, total acid compounds were more abundant than neutral compounds, whereas in the other the concentrations of both neutral and acid compounds were similar. Distinction of the chemotypes was based on the presence/absence of a sesquiterpene (germacrene d-4-ol acetate), neutral diterpenes (8(14),13(15)-abietadiene, anticopalol, an isomer of anticopalol, and pimarol), fatty acids (10-octadecenoic, 14-hydroxy-10-octadecenoic, and 13-hydroxy-9-octadenoic acids and an unidentified fatty acid), and resin acids (levopimaric + palustric, eperuic, and anticopalic acids, and three isomers of anticopalic acid); and on the different relative percentages of other compounds of these types. This study gives a wide view of the composition of the needles of Pinus pinaster, improving the differentiation of chemotypes on the basis of terpene and acid composition. © 2011 Springer-Verlag.

Wood of Quercus pyrenaica has suitable properties for the wine ageing process. However, the forest available for the barrel making from this particular type of tree is very limited. Nevertheless, it is highly advisable to use this kind of wood in order to manufacture alternative oak products. This study presents the results of ageing the same red wine using different pieces of wood (chips and staves) of Spanish oak (Q. pyrenaica), American oak (Quercus alba) and French oak (Quercus petraea) in conjunction with small, controlled amounts of oxygen. In addition, the phenolic parameters, colour and sensory analysis point out that wines aged with Q. pyrenaica pieces have similar enological characteristics to those aged with American or French oak pieces of wood (chips and staves). Furthermore, the total oxygen consumed and its relation with sensory properties also has been studied in this article in order to know how the oxygen behaves in these processes. Besides, it is going to put forward the fact that chips and staves from Q. pyrenaica oak are suitable for the ageing of red wines and better considered than American or French ones, showing higher aromatic intensity, complexity, woody, balsamic and cocoa. Finally, the tasters valued highly the wines with staves, pointing out its flavour and roundness in mouth. © 2012 Author(s).

Polyphenolic composition of two Syrah wines aged during 6 or 12 months in medium toasting acacia and oak 225 L barrels was studied by LC–DAD-ESI/MS. A total of 43 nonanthocyanic phenolic compounds were found in all wines, and other 15 compounds only in the wines from acacia barrels. Thus, the nonanthocyanic phenolic profile could be a useful tool to identify the wines aged in acacia barrels. Among all of them the dihydrorobinetin highlights because of its high levels, but also robinetin, 2,4-dihydroxybenzaldehyde, a tetrahydroxydihydroflavonol, fustin, butin, a trihydroxymethoxydihydroflavonol and 2,4-dihydroxybenzoic acid were detected at appreciable levels in wines during aging in acacia barrels, and could be used as phenolic markers for authenticity purposes. Although longer contact time with acacia wood mean higher concentrations of phenolic markers found in wines, the identification of these wines will also be easy after short aging times due the high levels reached by these compounds, even after only 2 months of aging.

Although oak wood is the main material used in cooperage, other species are being considered as possible sources of wood for the production of wines and their derived products. In this work we have compared the phenolic composition of acacia (Robinia pseudoacacia), chestnut (Castanea sativa), cherry (Prunus avium) and ash (Fraxinus excelsior and F. americana) heartwoods, by using HPLC-DAD/ESI-MS/MS (some of these data have been showed in previous paper), as well as the changes that toasting intensity at cooperage produce in each polyphenolic profile. Before toasting, each wood shows a different and specific polyphenolic profile, with both qualitative and quantitative differences among them. Toasting notably changed these profiles, in general, proportionally to toasting intensity and led to a minor differentiation amongspecies in toasted woods, althoughwealso found phenolic markers in toasted woods. Thus, methyl syringate, benzoic acid, methyl vanillate, p-hydroxybenzoic acid, 3,4,5-trimethylphenol and p-coumaric acid, condensed tannins of the procyanidin type, and the flavonoids naringenin, aromadendrin, isosakuranetin and taxifolin will be a good tool to identify cherry wood. In acacia wood the chemical markers will be the aldehydes gallic and _-resorcylic and two not fully identified hydroxycinnamic compounds, condensed tannins of the prorobinetin type, and when using untoasted wood, dihydrorobinetin, and in toasted acacia wood, robinetin. In untoasted ash wood, the presence of secoiridoids, phenylethanoid glycosides, or di and oligolignols will be a good tool, especially oleuropein, ligstroside and olivil, together verbascoside and isoverbascoside in F. excelsior, and oleoside in F. americana. In toasted ash wood, tyrosol, syringaresinol, cyclolovil, verbascoside and olivil, could be used to identify the botanical origin. In addition, in ash wood, seasoned and toasted, neither hydrolysable nor condensed tannins were detected. Lastly, in chestnut wood, gallic and

The volatile composition of the different oak wood pieces (chips of Quercus spp.) that can be found on the market to be used as alternatives to barrels for aging wines, as well as of chips of Quercus pyrenaica which are being introduced, was studied, evaluating the contents of volatile phenols, lactones, furanic compounds, pyranones, phenolic aldehydes, phenolic ketones, and others. In regard to the overall results, the volatile composition of these products varies widely and has not been clearly laid out according to either the oak species or the wood toasting intensity. Taking into account that the different characteristics of alternatives to barrel products are reflected in the wine treated with them and that an oenological profile based on these variables (origin and toasting level) cannot be defined, only an appropriate chemical analysis would reveal the quality of alternative-to-barrel products and allow us to attempt to foresee its effects on the chemical and organoleptic characteristics of the wines treated with them. On the other hand, the Q. pyrenaica alternative products are very similar to those of other species, with some aromatic particularities, such as their high levels of furanic compounds, eugenol, Furaneol, and cis-whiskylactone, and low levels of vanillin. © 2010 American Chemical Society.

The phenolic and tannic composition of heartwood extracts from Prunus avium, commonly known as cherry tree, before and after toasting in cooperage were studied using HPLC-DAD and HPLC-DAD/ESI-MS. Nonflavonoid (16 compounds) and flavonoid (27 compounds) polyphenols were identified, 12 of them in only a tentative way. The nonflavonoids found were lignin constituents, and their pattern is different compared to oak, since they include compounds such as protocatechuic acid and aldehyde, p-coumaric acid, methyl vanillate, methyl syringate, and benzoic acid, but not ellagic acid, and only a small quantity of gallic acid. In seasoned wood we found a great variety of flavonoid compounds which have not been found in oak wood for cooperage, mainly, in addition to the flavan-3-ols (+)-catechin, a B-type procyanidin dimer, and a B-type procyanidin trimer, the flavanones naringenin, isosakuranetin, and eriodictyol and the flavanonols aromadendrin and taxifolin. Seasoned and toasted cherry wood showed different ratios of flavonoid to nonflavonoid compounds, since toasting results in the degradation of flavonoids, and the formation of nonflavonoids from lignin degradation. On the other hand, the absence of hydrolyzable tannins in cherry wood, which are very important in oak wood, is another particular characteristic of this wood that should be taken into account when considering its use in cooperage. © 2010 American Chemical Society.

The phenolic and tannic composition of heartwood extracts from Castanea sativa Mill.;before and after toasting in cooperage, were studied using HPLC-DAD and HPLC-DAD/ESI-MS, and some low molecular weight phenolic compounds and hydrolyzable tannins were found. The low molecular weight phenolic compounds were lignin constituents as the acids gallic, protocatechuic, vanillic, syringic, ferulic, and ellagic, the aldehydes protocatechuic, vanillic, syringic, coniferylic, and sinapic, and the coumarin scopoletin. Their patterns were somewhat different those of oak because oak does not contain compounds such protocatechuic acid and aldehyde and is composed of much lower amounts of gallic acid than chestnut. Vescalagin and castalagin were the main ellagitannins, and acutissimin was tentatively identified for the first time in this wood. Moreover, some gallotannins were tentatively identified, including different isomers of di, tri, tetra, and pentagalloyl glucopyranose, and di and trigalloyl-hexahydroxydiphenoyl glucopyranose, comprising 20 different compounds, as well as some ellagic derivatives such as ellagic acid deoxyhexose, ellagic acid dimer dehydrated, and valoneic acid dilactone. These ellagic derivatives as well as some galloyl and hexahydroxydiphenoyl derivatives were tentatively identified for the first time in this wood. The profile of tannins was therefore different from that of oak wood because oak only contains tannins of the ellagitannins type. Seasoned and toasted chestnut wood showed a very different balance between lignin derivatives and tannins because toasting resulted in the degradation of tannins and the formation of low molecular weight phenolic compounds from lignin degradation. Moreover, the different toasting levels provoked different balances between tannins and lignin constituents because the intensity of lignin and tannin degradation was in relation to the intensity of toasting. © 2010 American Chemical Society.

The increasing demand for wood for barrel-making in addition to the rapid extension of alternative aging system, have led to looking into the possibility of utilizing Spanish oak. Quercus pyrenaica is the species that predominates in Spain, and the chemical composition of its heartwood (ellagitannins, low molecular weight phenolic and volatile compounds) and its incidence in characteristics of wine are similar to that of other species that are of recognized oenological quality for barrel-making, showing only quantitative differences with respect to French (Quercus petraea) and American (Quercus alba) species. However, at present, the quantity of good quality wood that we can obtain from the Q. pyrenaica Spanish forest is limited. Hence, in the short term, and considering the high chemical oenological quality of Q. pyrenaica wood, we propose the utilizing of chips, segments, staves, and other oak alternatives for wine aging, which would be obtained from wooden remnants from barrel-making as well as from trees with small diameters or physical defects which would normally be inappropriate for cooperage. With regards to the latter idea, studies on special chip-making processes, and other oak wood pieces are being carried out, especially focused on reducing seasoning time, and to toasting optimization as a function of wood piece size, in addition to its behaviour when incorporated into the different alternative aging systems. We present in this study the effect of seasoning way (traditional or unconventional) on volatile composition of Q. pyrenaica chips and staves at three toasting levels (light, medium and heavy), and the evolution of the wood-released aromatic composition of a Spanish artificially aged wine, using these alternative products. The wines showed in general small differences in their oak-derived characteristics, which were more related to the wood piece size and the toasting intensity than to the seasoning way, and they could be linked with the concentrati

The practice of wine aging in stainless steel tank involves storing wine in contact with wood and dosing it with small oxygen quantities in order to obtain a final wine more stable in time and with the same characteristics of barrel-aged wines. Oxygen dosing is a key factor and, to achieve a correct development of wine, needs to be applied according to wine necessities and to the kind of wood chosen. This paper shows the results obtained from the study of oxygen required by a same wine aged in tanks with different alternative products (chips and staves) made of American (Q. alba), French (Q. petraea) and Spanish oak (Q. pyrenaica), with a strategy of micro-oxygenation as required. The results indicate that the size and origin of the wood used determine the oxygen management during the process. In fact, wine treated with big pieces (staves) consumes more oxygen and, with regard to wood origin, wine aged with French oak (Q. petraea) products needs of a higher oxygen dosage. © 2009 Elsevier B.V. All rights reserved.

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.

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.

The chemical composition of heartwood from the Spanish oaks Quercus petraea and Q. pyrenaica includes a wide range of volatile compound families (volatile phenols, phenolic aldehydes, furanic compounds, lactones, phenyl ketones, and others), which are potentially extracted into wine during aging. Changes in volatiles during the natural seasoning process followed in barrel cooperage were studied. Volatile compounds varied during seasoning, with some increasing in concentration while others decreased or did not show significant variations. The evolution of the wood was most significant during the first two years of seasoning, followed by stabilization during the third year, with variations depending on species, origin, and seasoning environmental conditions. Copyright © 2007 by the American Society for Enology and Viticulture. All rights reserved.

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.

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.

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.

The volatile composition (volatile phenols, phenolic aldehydes, furanic compounds, lactones, phenyl ketones, and other related compounds) of Spanish oak heartwood of Quercus robur, Quercus petraea, Quercus pyrenaica, and Quercus faginea was studied by gas chromatography/mass spectrometry, in relation to the processing in barrels cooperage and in relation to the French oak of Quercus robur (Limousin) and Quercus petraea (Allier) and American oak of Quercus alba (Missouri), which are habitually used in cooperage. The volatile composition of seasoned oak woods varied according to individual trees, species, and origins, and the differences were more significant in Spanish species with respect to American species than with respect to French species. The toasting process influenced the volatile composition of wood. It led to high increases in the concentration of volatile phenols, furanic aldehydes, phenyl ketones, and other related structures, but the effect on w-lactones levels depended on species and origin. The volatile composition in Spanish oak species evolved during toasting like in French and American oak, but quantitative differences were found, especially important in American species with respect to European species.

A red Rioja wine was aged in barrels made of Spanish oak wood for 21 months. The evolutions of colour percentage intensity, families of phenolic compounds and low molecular weight phenolic compounds were studied in these wines and compared with those of the same wine aged in barrels made of French and American oak. The analysis of chromatic parameters and total anthocyanins indicates that the wines aged in Spanish and French oak wood barrels have similar chromatic characteristics, but are significantly different to those of wines aged in barrels made of American oak wood, indicating a different degree of modification of the colour. The ageing process also had an important influence on the low molecular weight polyphenols composition of wine. The evolution of these components allowed the production of wines with different characteristics, in relation to the type of wood used in barrel making process. On the other hand, Spanish oak wood can be considered suitable for barrel production for quality wines, since a wine aged in barrels made of Spanish oak wood showed similar and intermediate characteristics to those of the same wine aged in French and American oak woods.

Cork polyphenols susceptible to migrate into wine were studied in ten different types of natural and agglomerated cork stoppers, made of one and several pieces. Both low molecular weight polyphenols (LMWP) and ellagitannins (ET) were analysed by HPLC. Moreover, the molecular weight distribution was determined in tannic fractions. The LMWP gallic, protocatechuic, vanillic, caffeic, ferulic and ellagic acids; vanillin, protocatechuic, coniferilic and sinapic aldehydes, aesculetin and aescopoletin; and the ET castalagin, grandinin, vescalagin and roburin E were evaluated in all the samples. These LMWP and ET, found also in oak wood in different concentrations, play an important role in wine ageing. Although natural cork stoppers yielded, in general, higher amounts of polyphenols than agglomerated cork stoppers, no significant differences were found among the different types of cork stoppers. © Springer-Verlag 2001.

The evolution of tannins in Spanish oak heartwood of Quercus robur L.;Quercus petraea Liebl.;Quercus pyrenaica Wild.;and Quercus faginea Lam. was studied in relation to the processing of wood in barrel cooperage. Their evolution was compared with that of French oak of Q. robur (Limousin, France) and Q. petraea (Allier, France) and American oak of Quercus alba L. (Missouri), which are habitually used in cooperage. Two stages of process were researched the seasoning of woods during 3 years in natural conditions and toasting. Total phenol and total ellagitannin contents and optical density at 420 nm of wood extracts were determined. The ellagitannins roburins A-E, grandinin, vescalagin, and castalagin were identified and quantified by HPLC, and the molecular weight distribution of ellagitannins was calculated by GPC. During the seasoning process the different ellagitannin concentrations decreased according to the duration of this process and in the same way as those in French and American woods. The toasting process also had an important influence on the ellagitannin composition of wood. Roburins A-E, grandinin, vescalagin, and castalagin decreased during this process in the Spanish wood species, in the same proportion as in the French and American ones. Also, the seasoning and toasting processes lead to qualitative variations in the structure of ellagitannins, especially in the molecular weight distribution, as was evidenced by GPC analysis of their acetylated derivatives.

The evolution of low molecular weight polyphenols in Spanish oak heartwood of Quercus robur, Quercus petraea, Quercus pyrenaica, and Quercus faginea was studied by HPLC, in relation to the processing of wood in barrel cooperage. The polyphenolic composition of Spanish woods subjected to natural seasoning for 3 years and to the toasting process was studied in relation to those of French oak of Q. robur (Limousin) and Q. petraea (Allier) and American oak of Q. alba (Missouri), which are habitually used in cooperage. The concentrations of benzoic and cinnamic acids and aldehydes of Spanish woods increased during seasoning depending on the duration of this process and in the same way as those of French and American woods. The process having the main influence on the phenolic composition of wood was the toasting. It led to high increases in the concentration of phenolic aldehydes and acids, especially cinnamic aldehydes (sinapic and coniferylic aldehydes), followed by benzoic aldehydes (syringaldehyde and vanillin) and benzoic acids (syringic and vanillic acids). This polyphenolic composition in Spanish oak species evolved during toasting as in French and American oak, but quantitative differences were found, which were especially important in American species with respect to the others.

Chloroanisoles [2,4-dichloroanisole, 2,4,6-trichloroanisole (TCA), 2,3,4,6-tetrachloroanisole and pentachloroanisole], chlorophenols [2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol and pentachlorophenol (PCP)] and guaiacol were detected in red and white cork-tainted bottled wines. These compounds were also found in the cork stoppers from those bottles. A significant correlation was found between TCA in wines and TCA in cork stoppers, and between TCA in wine and intensity of cork taint. At low levels of TCA, the presence of guaiacol or PCP were also found to influence in cork taint. © Springer-Verlag 2000.

In this work, we study the low molecular-weight polyphenols in cork stoppers obtained from commercial wine bottles and in samples taken at five stages of the cork stopper manufacturing process. The phenolic compounds (acids, aldehydes, and coumarins) were analyzed by high pressure liquid chromatography with photodiode array detector. The results were studied by statistical methods in order to determine the relationship among these compounds and their variability throughout the industrial processing. Discriminant analysis showed that the phenolic composition allows differentiation of each stage in the manufacture of cork stoppers and the different provenances of stoppers obtained from commercial wine bottles. The results showed wide variations in phenolic content among cork stoppers within each region and each winery.

Low molecular weight polyphenols and ellagitannins were analyzed by HPLC, and the molecular weight distribution of ellagitannins was calculated by GPC, in oak heartwood of Quercus robur L.;Quercus petraea Liebl.;Quercus pyrenaica Wild.;and Quercus faginea Lam.;grown in Spain, before and after 1 year of seasoning, in Bordeaux, France. During this process, the concentrations of low molecular weight polyphenols (acids and aldehydes, benzoic and cinnamic, and coumarins) increased, and those of ellagitannins (castalagin, vescalagin, and roburins A-E) decreased. A similar behavior for the A and B compounds in all species was not found. This modification in the chemical composition was similar in the four Spanish species of Quercus studied and allowed the differentiation between the unseasoned wood and the wood after the first year of seasoning.

The variability of ellagitannin composition and its molecular weight distribution in unseasoned oak heartwood of four species grown in the North of Spain (Quercus robur, Q. petraea, Q. pyrenaica and Q. faginea) and in samples of Allier, Limousin and American oak were studied to know the differences in composition between Spanish oakwoods and oakwoods traditionally used in cooperage. The heartwood was processed into sawdust and total polyphenols, condensed tannins, and total ellagitannins were determined. Ellagitannins were analyzed by HPLC and GPC. Finally, the average, standard deviation, coefficient of variation and discriminant functions were calculated.

Tannic composition was studied in reproduction cork samples from three different trees of Spanish Quercus suber and at different industrial processing stages. The ellagitannins, roburins A and E, grandinin, vescalagin, and castalagin, were identified and quantified by HPLC. Global evaluations of tannins were also carried out, using classical chemical methods. The group of hydrolyzable tannins was the most abundant in the tannic extract in all samples; among them, castalagin was the main component, followed by vescalagin, grandinin, roburin E, and, to a much lesser extent, roburin A. The changes in tannic composition throughout the industrial processing are mainly related to the boiling process and are more pronounced in total phenol and proanthocyanidin contents than in individual ellagitannins content. Vescalagin and roburins A and E were selected as those variables that provided the greatest discrimination among stages. Important differences in the ellagitannin contents were observed among the trees studied, all of the ellagitannins being discriminant variables in this case.

Polyphenolic composition was studied by HPLC and classical chemical methods in reproduction cork of Quercus suber from different Spanish provenances. The low molecular weight polyphenols (gallic, protocatechuic, vanillic, caffeic, ferulic, and ellagic acids; protocatechuic, vanillic, coniferyl, and sinapic aldehydes; and aesculetin and scopoletin) and the ellagitannins (roburins A and E, grandinin, vescalagin, and castalagin) were identified and quantified. Ellagic acid was the main component in the ether soluble fraction, and the group of hydrolyzable tannins, and among them castalagin, was the most abundant in the tannic extract in all the samples. Although there was an important variability among provenances, no significant differences were found in the total tannin content and in the individual content of each ellagitannin. However, gallic and caffeic acids and protocatechuic aldehyde provided the greatest discrimination among provenances.

Tannin composition (proanthocyanidins and ellagitannins) of branch wood extracts from Eucalyptus camaldulensis, E. globulus and E. rudis is studied by HPLC and classical chemical assays. HPLC analysis revealed the presence of a wide variety of both types of tannins. The wood of the Eucalyptus species studied shows qualitative and quantitative variability according to the species and the origin of the samples.

Polyphenols of adult leaves from Eucalyptus globulus, E. camaldulensis and E. rudis grown in Spain, in two areas with different edaphoclimatical characteristics, were estimated by chemical methods and by high pressure liquid chromatography. Leaf extracts consisted mainly of proanthocyanidins, ellagitannins and flavonol glycosides. Knowledge of the ellagitannins allows the discrimination of the three species, with E. globulus being well differentiated from the other two. However, the pattern of flavonol glycosides only permitted the discrimination of E. rudis with respect to E. camaldulensis and E. globulus.

In this work, a study on tannins (proanthocyanidins and ellagitannins) is carried out in bark extracts from different Eucalyptus species grown in Spain E. camaldulensis, E. globulus and E. rudis. The tannin analysis was carried out using HPLC and classical chemical methods. Bark extracts were characterized by the abundance of polymeric proanthocyanidins and by the diversity of ellagitannins. The ellagitannins composition was related with the species and the tree provenance, allowing to discriminate E. globulus from E. camaldulensis and E. rudis.