Extraction of oak volatiles and ellagitannins compounds and sensory profile of wine aged with French winewoods subjected to different toasting methods: Behaviour during storage

a b s t r a c t In Merlot wines the evolution of volatile and non-volatile (ellagitannins) compounds extracted from winewoods while being macerated for 12 months was studied. Seven types of winewoods subjected to different toasting methods were used. Different rates of extraction, depending mainly on wood compounds origin (toasting or naturally present in wood) and on the watering process during toasting, were observed, which were reflected in sensory differences. Globally, volatile phenols together with aldehydes, phenols and lactones showed an increase with increasing maceration time. Ellagitannins were extracted faster during the first 3 months; after 6 months an important decrease was observed. Wines with winewoods subjected to watering during toasting were lower in ellagitannins concentrations and demonstrated the greatest decrease of these compounds during maceration. Astringency and bitterness intensified with increasing ellagitannins. Lactones induced positive sweetness sensations, whereas furanic and guaiacol compounds influenced bitterness and astringency. Spicy and vanilla descriptors were related to eugenol, vanillin and other odorous chemicals

Impact of oak wood ageing modalities on the (non)-volatile composition and sensory attributes of red wines

During fermentation or ageing of wines, oak wood is commonly used in form of barrels, casks or derived oak products (chips, winewoods, tankstaves, among others). It is well known that aroma, structure, astringency, bitterness, aromatic persistence and colour may change as a result of wine-wood contact. A full-scale experimentation was performed under different oak ageing conditions in order to evaluate colour, phenolic, aromatic and sensory differences among final red wines (9-months ageing). Oenological parameters and wine colour were not impacted by ageing modality. At the end of ageing, no differences were found in total phenolic and tannin contents. Regardless of the ageing modality, total content and profile of fruity volatiles were globally maintained with regard to control (? 86 %). In contrast, the higher the surface of wine-wood contact per unit of wine volume, the greater the extraction of woody aromas. Thus, barrels led to wines with the highest level of woody aromas (515-864 ?g/L), followed by cask modalities (430-470 ?g/L). From a sensory point of view, descriptors highlighting the woody character of wine (vanilla, spicy) were enhanced in all oak-aged wines when compared to control. However, our results indicate that a masking effect of fruity aroma by oak wood did not occur, since all modalities were perceived as fruity as the control. Thus, each oak ageing modality may lead to wines with a different woody character, without no impact on fruity perception, allowing wineries to achieve the targeted aromatic profile, good structure and just the right balance between fruity and woody aromas

Migration of polyphenols from natural and microagglomerated cork stoppers to hydroalcoholic solutions and their sensory impact

During bottling aging, the wine comes into contact with the cork stopper due to the horizontal position of the bottle. The release of compounds, such as cork phenolic compounds, thus take place between the cork and the wine, depending on the type of cork stopper and the surface treatments applied. Many publications describe the extraction of these phenolic compounds in wine or hydroalcoholic solutions from natural corks, but few address microagglomerated corks, which are increasingly used by winemakers to seal their bottles. The aim of this study was therefore to compare the polyphenols, mainly hydrolysable tannins, transferred from natural and microagglomerated corks treated with supercritical CO2 into hydroalcoholic solutions. For this purpose, polyphenols released in macerates of natural and microagglomerated cork stoppers were identified and quantified by HPLC-DAD-ESI-QQQ. Suberic acid was also quantified. In this study, despite the high intra-“natural cork stopper” variability, significant differences were found between both types of stoppers for all polyphenols, the agglomerated corks releasing significantly less polyphenols; i.e., 25 times less. In contrast, suberic acid was extracted from both types of corks in similar concentrations; therefore, its extractability was not impacted by the type of stopper. A sensory profile was also carried out on the macerates. Macerates of natural cork stoppers were perceived with notes of “cardboard, dust, plank, wood” and “cork taint” significantly higher than supercritical CO2 treated microagglomerated cork stopper macerates. Moreover, the natural cork macerate with the highest content in polyphenol was perceived as being more bitter than that of microagglomerated cork stoppers

Sensory characterisation of Cognac eaux-de-vie aged in barrels subjected to different toasting processes

Toasting is a key step in the barrel-making process. It plays an important role in the breakdown of oak wood compounds and thus influences the chemical composition and organoleptic properties of wines and brandies. However, the effect of toasting on distilled spirit quality has not yet been extensively studied. The objective of this study was therefore to study the impact of toasting on cognac eaux-de-vie by characterising the eaux-de-vie sensorially after 12 months of ageing. Eight eaux-de-vie aged in barrels with 8 different toasts were studied. The 8 toasts represented 4 different temperatures (low, medium, medium plus and high) and two toasting lengths for each temperature (one so-called “normal” and the other “slow”). Sensory analysis was carried out on these eaux-de-vie through several tests. First, a sorting test showed the differences between the samples and then training was carried out on previously chosen descriptors in order to build a sensory profile and perform a ranking test. The study was realised for two alcohol levels: 60 % (v/v), which is the alcohol level of eaux-de-vie in barrels, and 40 % (v/v), which is the alcohol level of a commercial cognac. This approach demonstrated that barrel toasting generally leads to significant sensorial differences in eaux-de-vie during ageing. These differences are greater between a lightly and a highly toasted barrel. This study is a first step in the characterisation of cognac eaux-de-vie aged in barrels made with different toasts

Wine acidification methods: a review

Global warming is directly linked to a lower concentration in organic acids in grape berries, leading to higher pHs in wine. Because of this lack of acidity, many important factors are impacted, as wine acidity and pH play a crucial role in various equilibriums. Indeed, the lower acidity and the higher pH modify the parameters of wine, such as free and molecular sulfur dioxide availability, colour and sensory aspects. Therefore, it is an ongoing challenge for winemakers to deal with wine acidification and thus preserve wine physico-chemical properties and prevent early spoilage due to microbiological instability induced by high pH. Different acidification methods are allowed by the OIV, chemical acidification being one the most common, followed by physical acidification and microbiological acidification. This review examines these three methods of acidification. The first part details chemical acidification and gives a complete description of various organic acids used in winemaking, and their different properties and regulations; the second part focuses on physical acidification, such as cation exchange resins and electrodialysis; and the last part briefly reviews the novelty of microbiological acidification in wine

Impact of acidification at bottling by fumaric acid on red wine after 24 months

Le réchauffement climatique est directement lié à une baisse de concentration d'acides organiques dans les baies de raisin. En raison de ce manque d'acides organiques, les vins ont tendance à avoir des niveaux de pH plus élevés et une faible acidité titrable. De nombreux facteurs importants sont impactés, tels que les équilibres chimiques, microbiologiques et organoleptiques. Il est courant d'acidifier le vin afin d'éviter ces déséquilibres qui peuvent entraîner des défauts du vin et une altération précoce. L'acide tartrique (AT) est le plus souvent utilisé par les vinificateurs pour acidifier le vin. En tant que candidat potentiel à l'acidification, l'acide fumarique (AF), autorisé par l'OIV dans ses états membres pour l'inhibition de la fermentation malolactique, pourrait également être utilisé car il possède un meilleur pouvoir acidifiant que l'acide tartrique. Ainsi, l'objectif de la présente étude était d'étudier l'impact de l'ajout d'AF à la mise en bouteille par rapport à l'AT sur la qualité du vin blanc. Pour ce faire, un vin rouge Cabernet Sauvignon sans sulfites a été divisé en deux lots, dont l'un a été sulfité à 80 mg/L. Les deux lots, sans sulfites et sulfité, ont ensuite été redivisés en cinq lots, dont un sans aucun ajout, deux des lots dans lesquels l'AT a été ajouté à des concentrations de 1,25 et 2,5 g/L respectivement, et deux lots dans lesquels l'AF a été ajouté à des concentrations de 1, et 2 g/L, respectivement. Les paramètres oenologiques classiques (pH, acidité titrable), les paramètres de couleur (intensité de la couleur, CIELAB), les composés phénoliques totaux (IPT, Folin), ainsi que les capacités antioxydantes (CUPRAC, DPPH), les tanins totaux, les anthocyanes totaux et leur composition (analyse HPLC) ont également été analysés. Des analyses sensorielles ont également été réalisées sur les vins afin d'évaluer l'impact organoleptique de l'ajout d'AF.Global warming is directly linked to a lower concentration of organic acids in grape berries. Because of this lack of organic acids, wines tend to have higher pH levels and low titrable acidity. Many important factors are impacted, such as the chemical, microbiological and organoleptic equilibriums. It is common practice to acidify the wine in order to prevent these imbalances that can lead to wine defects and early spoilage. Tartaric acid (TA) is most commonly used by winemaker for wine acidification purposes. As a potential acidification candidate, fumaric acid (FA), authorized by the OIV in its member states for the inhibition of malolactic fermentation, could also be used since it has a better acidifying power than tartaric acid. Thus, the objective of the present study was to investigate the impact of the addition of FA at bottling in comparison to TA on white wine’s quality. For this purpose, a sulfite-free Cabernet Sauvignon red wine was divided into two batches, one of which was sulfited at 80 mg/L. The two batches, sulfite-free and sulfited, were then redivided into five batches, one of which without any addition, two of the batches in which TA was added at concentrations of 1.25 and 2.5 g/L respectively, and two batches in which FA was added at concentrations of 1, and 2 g/L, respectively. Classical oenological parameters (pH, titratable acidity), color parameters (color intensity, CIELAB), total phenolic compounds (IPT, Folin), as well as total tannins, total anthocyanins and their composition (HPLC analysis) were analyzed. Sensory analyses were also performed on the wines in order to assess the organoleptic impact of FA addition

Wine acidification methods: a review

Global warming is directly linked to a lower concentration in organic acids in grape berries, leading to higher pHs in wine. Because of this lack of acidity, many important factors are impacted, as wine acidity and pH play a crucial role in various equilibriums. Indeed, the lower acidity and the higher pH modify the parameters of wine, such as free and molecular sulfur dioxide availability, colour and sensory aspects. Therefore, it is an ongoing challenge for winemakers to deal with wine acidification and thus preserve wine physico-chemical properties and prevent early spoilage due to microbiological instability induced by high pH. Different acidification methods are allowed by the OIV, chemical acidification being one the most common, followed by physical acidification and microbiological acidification. This review examines these three methods of acidification. The first part details chemical acidification and gives a complete description of various organic acids used in winemaking, and their different properties and regulations; the second part focuses on physical acidification, such as cation exchange resins and electrodialysis; and the last part briefly reviews the novelty of microbiological acidification in wine

Impact of acidification at bottling by fumaric acid on red wine after 24 months

Global warming is directly linked to a lower concentration of organic acids in grape berries. Because of this lack of organic acids, wines tend to have higher pH levels and low titrable acidity. Many important factors are impacted, such as the chemical, microbiological and organoleptic equilibriums. It is common practice to acidify the wine in order to prevent these imbalances that can lead to wine defects and early spoilage. Tartaric acid (TA) is most commonly used by winemaker for wine acidification purposes. As a potential acidification candidate, fumaric acid (FA), authorized by the OIV in its member states for the inhibition of malolactic fermentation, could also be used since it has a better acidifying power than tartaric acid. Thus, the objective of the present study was to investigate the impact of the addition of FA at bottling in comparison to TA on white wine’s quality. For this purpose, a sulfite-free Cabernet Sauvignon red wine was divided into two batches, one of which was sulfited at 80 mg/L. The two batches, sulfite-free and sulfited, were then redivided into five batches, one of which without any addition, two of the batches in which TA was added at concentrations of 1.25 and 2.5 g/L respectively, and two batches in which FA was added at concentrations of 1, and 2 g/L, respectively. Classical oenological parameters (pH, titratable acidity), color parameters (color intensity, CIELAB), total phenolic compounds (IPT, Folin), as well as total tannins, total anthocyanins and their composition (HPLC analysis) were analyzed. Sensory analyses were also performed on the wines in order to assess the organoleptic impact of FA addition

Phenolic Compounds of Grapes and Wines: Key Compounds and Implications in Sensory Perception

Phenolic compounds are a wide family of thousands of natural bioactives well-known for their overwhelming demonstrated health benefits. Particularly in wines, polyphenols and quality are closely interconnected. Indeed, these compounds possess a critical role due to their contribution to organoleptic wine quality as color, astringency, and bitterness. The profile or the composition of certain polyphenols has been even proposed as an analytical tool for authenticity certification. In this sense, although important progress has been achieved, the understanding of the relationship between the quality of a particular wine and its phenolic composition remains one of the major challenges in enology research. But why? If there is an adjective to define wine, it is “complex.” This final complexity of a wine begins with the enormous polyphenolic variability that may be present in grapes influenced by ripening, genetic, or environmental factors, among others. Winemaking process (alcoholic and malolactic fermentation) and wine aging with or without wood contact produce endless reactions giving rise to complex transformations (copigmentation, cycloaddition, polymerization, and oxidation) of polyphenols. This chapter gathers the most relevant information about the composition, variations, and transformations of phenolic compounds from grape to wine including their influence on sensory properties