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Volatile aroma compounds and wine sensory attributes
Abstract
This chapter presents a revision of our knowledge and understanding of the role played by the different aroma chemicals in the positive aroma attributes of wine. In Section 1.1, some basic concepts concerning the characteristics of aroma chemicals, such as thresholds, odour activity values (OAVs) and the relationship between the intensity of odour and the concentration are presented. After this, a systematic approach to classifying the different aroma chemicals of wine is presented. One basic idea is that all wines share a common basic aromatic structure formed by ethanol and 27 different aroma compounds, most of them by-products of fermentation. The mixture of those products has the typical vinous aroma and exerts an aroma-buffering effect with the ability to suppress the effect of many odorants added to it, particularly those with fruity characteristics. The ability of the different odour chemicals to break such a buffer, and hence transmit a different aroma nuance to the wine, and the relationship between the transmitted aroma nuance and the aroma of the chemical are used to define the different roles played by aroma compounds on wine aroma. These roles can be as impact compounds, major contributors, net contributors, subtle aroma compounds, aroma enhancers and aroma depressors. The subjects can be individual aroma chemicals or well-defined mixtures of molecules sharing chemical and odour properties (aroma families). Different examples of the aroma chemistry behind some of the most relevant wine aroma nuances from simple or complex wines are also presented and discussed.
... Through odor recombination, addition and omission studies, more refined contribution of odorants can be determined (V. Ferreira, 2010;Frank, Wollmann, Schieberle, & Hofmann, 2011;Grosch, 1993;Nicolotti, Mall, & Schieberle, 2019). Based on their contribution in wines, the detected odor-active compounds can be divided into 1) genuine impact compounds or key odorants, 2) major contributors, 3) net contributors, 4) secondary or subtle contributors, and 5) aroma enhancers and aroma depressors (V. ...
... Based on their contribution in wines, the detected odor-active compounds can be divided into 1) genuine impact compounds or key odorants, 2) major contributors, 3) net contributors, 4) secondary or subtle contributors, and 5) aroma enhancers and aroma depressors (V. Ferreira, 2010). All the odorants with OAV above 1 are considered as main contributors (key odorants, major contributors and net contributors). ...
... key odorants are normally present above their recognition threshold, and they provide the distinct aroma characteristic to the wine (V. Ferreira, 2010). In icewines, β-damascenone was shown to be a key odorant that not only transmits its honey-like aroma to the icewines but also influences the entire aroma typicality (Ma et al., 2017). ...
Icewine was used as an experimental object, and hundreds of wine- or food-related odor mixtures were designed and investigated for the first time based on the identification and analysis of icewine’ odorants. The aim of the thesis work was to explore the key odor elements that affected the perception of odor mixtures and the general laws behind olfactory perceptual interactions. The thesis manuscript contains seven chapters:The first review of the literature gives a brief introduction to the olfactory system and odor perception. Then, odorants’ mixture perception is highlighted through examples of interactions between odorants at the perceptual level. Research progress in perceptual interactions between odorants observed in foods and beverages and methodologies involved in the researches of perceptual interactions are also briefly summarized.The second review of the literature aims to provide comprehensive information related to our research objects, the odor of a special wine, namely icewine, which made from late harvested and frozen grapes by unconventional production process. The uniqueness of icewine’s aroma, the mechanism of odor generation in icewine and the effects of natural and human factors in the vineyard and winery on aroma composition of icewines are systematically summarized. The current research status and future research needs of icewine aroma are also put forward in this chapter. Some of these research needs are exactly the content included in this thesis.The first study analyzed the odorants and the odorants’ aroma perception in icewine. In this study, the key aroma compounds of Chinese Vidal icewine were characterized by means of gas chromatography–olfactometry (GC-O) coupled with mass spectrometry (MS) on polar and non-polar columns. Aroma recombination experiments and omission tests were used to verify and rank the aroma contribution for investigating the key aroma compounds.The second study is among the very first attempts to evaluate the contribution of odor-active compounds considering the mixture-induced perceptual effect on a complex aroma (here icewine). In this study, we used the advanced Olfactoscan setup, which allowed us to consider the impact of a single odorant, identified by GC × GC−TOFMS, on the global wine aroma delivered as a background odor during GCO analysis. To analyze the data, a new semiautomatic method was applied to allow the identification of odor zones in a similar way both in GCO and Olfactoscan approaches based on the detection frequency method (19 trained judges).The third study systematically explored the perceptual interactions between key odor-active compounds. Based on the findings of the first two studies, more than 150 odor mixtures samples, related to the key odorants of icewine and wine aroma vectors, were designed to assess the influence of odor intensity, number of odorants in the mixture, and combinations of odorants on the overall perception. The experiment was performed with a 12-channels computer-controlled dynamic-dilution olfactometer.The last study selected 72 representative odorants in food and beverage systems based on the differences in their structural parameters, and 222 sets of binary odor mixtures were designed among the 2556 possible combinations. By measuring the intensity and pleasantness of the binary odor mixtures and of their two unmixed components, general laws of perceptual interactions, as well as hypotheses on their putative influencing factors in a simple system are established.The manuscript ended with a general conclusion and discussion (Chapter 7) about the four studies conducted, then the innovation of this work and the perspectives for further research were addressed.
... More than 800 VOCs have been identified in wines, with a concentration range varying from hundreds of mg/L to µg/L or ng/L levels [34]. However, only some of them work as odor-active molecules, mainly in concentrations above their sensory perception threshold but also because of synergistic or masking effects at peri/sub-threshold levels [35][36][37][38][39][40]. In wine, VOCs are divided in four groups, each of them containing several chemical classes: (i) grape and varietal VOCs, which are present in the cells of the berries as free volatile molecules (e.g., methoxypyrazines, varietal thiols, and monoterpenoids) or as glycosidic, aminoacidic/peptidic precursors (i.e., unsaturated fatty acids, phenolic acids, S-cysteine conjugates, dimethylsulfide precursors, carotenoids, and glycoconjugates); (ii) pre-fermentative VOCs, which are formed during the first processing steps such as crushing, pressing, and skin contact, or by thermal, chemical, and enzymatic reactions in the must (e.g., six carbon atoms (C6) aldehydes and alcohols); (iii) fermentative VOCs, which include yeasts and bacterial by-products responsible for the background aroma of any wine and obtained from the main biochemical transformations of alcoholic and/or malolactic fermentations (e.g., esters, higher alcohols, volatile fatty acids, aldehydes and ketones, fermentative sulfur aroma compounds); (iv) maturation/aging VOCs, which refer to the aroma bouquet that develops during wine aging and/or extracted from wood barrels (e.g., furanic compounds, lactones, phenolic aldehydes, volatile phenols, phenyl ketones). ...
... Based on results by Dufour and Bayonove [51] suggesting that monomeric or oligomeric/polymeric polyphenols can differently impact aromas volatility, this behavior could be linked to the lower concentration of polymeric polyphenols [64] of young-red wines compared to aged ones. Considering the sensory importance of these odorants and that they act in combination with each other [39], it could be hypothesized that the PPhs composition of wine could impact the olfactory perception of monoterpenes. ...
... Based on results reported above and on the knowledge that esters act synergistically in imparting fruity notes to wine [39], the observed changes of most hydrophobic esters at increased levels of PPhs could have a significant sensory impact on wine fruity aroma. In addition, the observed decreases of isoamyl acetate, a molecule having an important olfactory role in wine, could be significant [39]. ...
Wine polyphenols (PPhs) and volatile organic compounds (VOCs) are responsible for two of the main sensory characteristics in defining the complexity and quality of red wines: astringency and aroma. Wine VOCs’ volatility and solubility are strongly influenced by the matrix composition, including the interactions with PPhs. To date, these interactions have not been deeply studied, although the topic is of great interest in oenology. This article reviews the available knowledge on the main physicochemical and sensory effects of polyphenols on the release and perception of wine aromas in orthonasal and retronasal conditions. It describes the molecular insights and the phenomena that can modify VOCs behavior, according to the different chemical classes. It introduces the possible impact of saliva on aroma release and perception through the modulation of polyphenols–aroma compounds interactions. Limitations and possible gaps to overcome are presented together with updated approaches used to investigate those interactions and their effects, as well as future perspectives on the subject.
... Therefore, it is of capital importance to try to know how these compounds or their precursors change during grape ripening, in order to understand the quality of the grapes at harvest, and in order to estimate the effects of grape composition on the final wine composition. For example, acetaldehyde is a compound found in all wines (Ferreira, de-la-Fuente-Blanco, & Sáenz-Navajas, 2019) and it is its major oxidation-related aldehyde (Bueno et al., 2018); therefore it has been studied in wines with oxidative aging, like Porto or Sherry wines (Zea, Serratosa, Mérida, & Moyano, 2015) and oxidized wines. The sensory involvement of this compound can be very important in small concentrations, since it has been shown that it can drastically reduce fruit attributes in varieties such as Sauvignon blanc (Coetzee, Brand, Jacobson, & Du Toit, 2016). ...
... One essential part of the aroma in neutral wines such as Moristel is the aromatic buffer (Escudero et al., 2004). This consists of a blend of different molecules containing the most important metabolites of alcoholic fermentation, such as ethanol, higher alcohols or fusel alcohols, fatty acids and ethyl esters, acetoin, diacetyl and acetaldehyde (Ferreira et al., 2019). The term buffer comes from the fact that this set of compounds can suppress a large number of sensory notes; however, they are also responsible for the vinous note (Ferreira et al., 2019). ...
... This consists of a blend of different molecules containing the most important metabolites of alcoholic fermentation, such as ethanol, higher alcohols or fusel alcohols, fatty acids and ethyl esters, acetoin, diacetyl and acetaldehyde (Ferreira et al., 2019). The term buffer comes from the fact that this set of compounds can suppress a large number of sensory notes; however, they are also responsible for the vinous note (Ferreira et al., 2019). ...
... Studies have attempted to classify, define and predict the relative importance of single compounds and their aromatic families in mixtures, highlighting the influence of sub-and peri-threshold compounds in complex blends (Atanasova et al. 2005, Ryan et al. 2008, Ferreira 2010, San-Juan et al. 2011, Ferreira 2012a. Only a few studies have used the approach of experimentally designed reconstitution of wines assessed by quantitative descriptive analysis (QDA) to determine both the intensity and quality of specific sensory attributes, examples include King et al. (2011), Frost et al. (2017 and Tomasino et al. (2020). ...
... The 'aroma buffering' Table 2. Table 5. F-ratios, probability values and mean square error from the pooled analysis of variance for the peach ethyl esters confirmatory sensory study. capacity of wine proposed by Ferreira (2010) may also be contributing to the inability of OAVs to predict attribute intensities. ...
... The overall aroma intensity of the samples was low to moderate in both peach reconstitution studies, with the Peach note described by panellists as 'vivid' but subtle during a post study discussion. The moderate intensity scores in the peach study and modest F-ratios for significant linear effects do not agree with the large calculated OAVs for ethyl esters (Tables 4, 5, S7) in the commercial wines studied, which are also commonly found in almost all young wines of any cultivar This discrepancy has been argued again to be related to an aroma buffer effect of the main common odour compounds in wine (Ferreira 2010), but might also be due to panellists reaching a compressive phase (saturation) of a psychophysical concentration-intensity function for an odorant (Marin et al. 1991)-a common feature of sensory stimulus-described in detail by Keast and Breslin (2003) for taste compounds. Evidence that the panel response was 'saturated' and the intensity plateaued for Peach aroma in the confirmatory study is seen by the downward curve for ethyl octanoate (significant square term) in Figure 5a. ...
Background and Aims
The sensory experience of wine aroma is challenging to study. Given the presence of numerous and trace level volatiles, the subtle aroma nuances involved, as well as the complexity of human odour processing, the contribution of individual compounds and mixtures can be difficult to determine. In white wines, the volatile compounds eliciting stone fruit aromas are not well understood.
Methods and Results
Factorial designs were used with odorants added to model wine and assessed using sensory quantitative descriptive analysis. In model Viognier-like wines, several monoterpenes were confirmed to convey stone fruit attributes Apricot and Peach, which were strongly suppressed by aldehydes which imparted Cardboard-like odours. Importantly, lactones increased Apricot aroma when combined with the monoterpenes. For model unoaked Australian Chardonnay wine, sensory-directed screening followed by factorial studies showed that aliphatic ethyl esters, in particular ethyl octanoate, directed Peach aroma. Fatty acids were strong suppressors of the Peach attribute and gave Cheesy odours.
Conclusions
Apricot and peach aromas in Viognier and Chardonnay, although perceptually similar, were caused by different chemical compound families: grape-derived monoterpenes with lactones and yeast-derived fatty acid ethyl esters, respectively.
Significance of the Study
Having confirmed the compounds responsible for apricot and peach white wine aromas, there is potential to modify their concentration through established viticultural and winemaking practices.
... Introduction cannot be easily broken (Ferreira, 2010). For example, if the wine concentrations in acetic acid are low, fusel alcohol acetates are hydrolyzed and can be found at appreciable concentrations only in young wines. ...
... This is confirmed throw different studies, on the example of fermentative volatiles, primarily esters and higher alcohols (Ugliano and Henschke, 2009). A good example is the influence of ethyl esters on the perception of fruity aromas in some red wines, such as Cabernet sauvignon and Merlot, in which the content of compounds of this group is significantly higher, compared to some other varieties, in which the concentrations of these esters are typically much lower, like in Pinot noir, and therefore are not considered to be important factors contributing to its aroma (Ferreira, 2010). ...
... In the case of isoamyl acetate, below 0.02 mg/L this compound is just one of the many sweet-fruity wine compounds with very weak sensory effect. Between 0.2 and 1.4 mg/L, the importance of isoamyl acetate grows to the point that it becomes a quite important contributor to the fruity note of the wine (Ferreira, 2010). Isoamyl acetate is the only ester capable of imparting its characteristic aroma nuance to wines; in wines made with Pinotage or Tempranillo varieties, it is a characteristic aroma compound (van Wyck et al., 1979;Ferreira et al., 2000). ...
“Portugizac Mlado vino” is a local red wine with Protected designation of origin and Traditional term, and it is usually consumed very soon after alcoholic fermentation as a young wine. The maturation and aging of the wine affect the aroma composition, which is generally not pronounced and specific in the case of most red wines, but, as a sensory property, it is important for the perception of quality and consumer choice. The objective of this work was to analyze the most important aroma compounds of esters and higher alcohols, with the unpleasant volatile phenols too, in “Portugizac” wines, related to aging. The 9 young wines “Portugizac”, PDO “Plešivica” were analyzed after 3 and after 15 months of bottle storage at 16 ºC. Ethyl esters of butanoic and hexanoic acid along with isoamyl acetate are considered to be the most important esters in the fruity aroma of wine, and their concentrations in all analyzed “Portugizac” young wine samples were higher than their perception thresholds. The concentration of ethyl acetate was in the range 30-123 mg/L. The concentrations of ethyl esters of octanoic and decanoic acid, as well as 2-phenyl ethyl acetate and diethyl succinate in all analyzed wines, were lower than their perception thresholds. The concentrations of higher alcohols were much higher than their perception threshold. Bottle storage significantly affected the concentrations of analyzed compounds; after 15 months, the concentrations of acetate and ethyl esters (except ethyl acetate and diethyl succinate), as well as terpene (linalool), decreased, while higher alcohols and ethyl phenols slightly increased if compared to three months. In general, the compounds responsible for the desired fresh, fruity aroma tones were altered in an undesirable manner, while, undesirable compounds of 4-ethyl-phenol and 4-ethyl-quaiacol, which were not present in young wines, were detected in aged wines. It can be concluded that the bottle aging affects the aroma profile, undesirable changes were more pronounced than positive ones and therefore the consumption of young wine “Portugizac” might be more sensory attractive.
... The bound fraction of C6 compounds was very small and few changes were found due to grape sonication ( Table 2). Terpenes and their derivatives have a great sensory impact in wines from aromatic varieties such as Muscat, due to their low odor thresholds and pleasant aromas (floral or fruity), but they are less relevant in the aroma of wines from other grape varieties, especially in the case of red wines [38]. Although they come from the grape, many of them undergo modifications during fermentation, mainly by the liberation of its precursors due to the possible glycosidic activity of yeasts [4,39]. ...
... Fermentation compounds are the main contributors to the aroma of young wines, especially those from non-aromatic grape varieties, and constitute the base of wine aroma [38]. Figure 2 shows the total concentrations of the main groups of volatile compounds formed during alcoholic fermentation in control and treated wines. ...
... Within the group of pyrans and furans, three lactones (-butyrolactone, -nonalactone, pantolactone) were quantified in tested wines. Lactones can contribute positively to the aroma of wines, and some of them have stood out as important odorants [38]. -Nonalactone, with a coconut-like aroma, has a low odor threshold (30 g/L) [48]. ...
This study presents the effect of the application of high-power ultrasound to crushed grapes, at a winery-scale, on the content of varietal volatile compounds (free and glycosidically-bound) in musts and on the overall aroma of wines. Two different frequencies (20 kHz and 28 kHz) were tested and the combination of grape sonication and different maceration times on wine aroma was also evaluated. The volatile compounds were isolated by solid phase extraction and analyzed by gas chromatography-mass spectrometry, carrying out a sensory evaluation of wines by quantitative descriptive analysis. Sonication produced an increase in the concentration of free varietal compounds such as C6 alcohols, terpenes and norisoprenoids in musts and also in wines made by 48 h of skin maceration, being less efficient in the extraction of the bound fraction. Fermentation compounds were also positively affected by ultrasound treatment, although this effect was variable depending on the frequency used, the maceration time and the type of compound. All the wines made from sonicated grapes had better scores in the evaluated olfactory attributes with respect to the control wines. Our results indicate that sonication could produce an increase in the content of some volatile compounds of sensory relevance, obtaining wines with an aroma quality similar or higher than those elaborated with longer maceration times.
... The concentration of each volatile compound was divided by the corresponding odor threshold reported in the literature, giving the Aroma Index [25], or also called odor activity value [26]. As compounds present in concentrations higher than their odor threshold are considered as aroma-contributing substances, the compounds that exhibit an Aroma Index > 1 were considered to contribute individually to apple aroma [26]. ...
... The concentration of each volatile compound was divided by the corresponding odor threshold reported in the literature, giving the Aroma Index [25], or also called odor activity value [26]. As compounds present in concentrations higher than their odor threshold are considered as aroma-contributing substances, the compounds that exhibit an Aroma Index > 1 were considered to contribute individually to apple aroma [26]. An Aroma Index higher than 1000 corresponds to compounds that have a higher impact in aroma, presenting an odor intensity in the suprathreshold area. ...
... The relationship between perceived intensity and stimulus concentration was described by Fechner as a derived logarithmic function, which is the product of the Aroma Index and Weber-Fechner coefficient (2.33), plus 0.5 [27,28]. There is an intensity scale where 0 corresponds to "no odor", 1 is "very faint odor", 2 is "faint odor", 3 is "distinct odor", 4 is "strong odor", 5 is "very strong odor", and 6 or more correspond to "overwhelming odor", where the saturation is attained at 10 [26,28]. ...
Apple concentrate juice industry generates a flavored coproduct (apple aroma) recovered in the evaporation process, which is poorly valuated due to the lack of chemical characterization and standardization. In this study, industry apple aroma was characterized, allowing for the identification of 37 compounds, the majority esters (20), alcohols (7), and aldehydes (4). The storage temperature did not affect its volatile composition. Five key compounds were selected and monitored for 10 months of storage, and also compared with other three productions of another season allowing for observation of the same Aroma Index. Apple pomace was also used to produce a hydrodistillate. Contrary to the apple aroma, apple pomace hydrodistillate was unpleasant, reflected in a different volatile composition. Although no additional aroma fraction could be obtained from this wet byproduct, when dried, apple pomace presented 15 volatile compounds with toasted, caramel, sweet, and green notes. The infusions prepared with the dried apple pomace exhibited 25 volatile compounds with a very pleasant (fruity, apple-like, citrus, and spicy notes) and intense aroma. The addition of sugar changed the volatile profile, providing a less intense flavor, with almond, caramel, and sweet notes. These results show that apple aroma and pomace are high-quality flavoring agents with high potential of valuation as food ingredients.
... The series used were fruity, stewed apple/quince, grapefruit, floral, fresh/minty, vinous, spicy, green, reductive, fermentative and evolutive. The series were made in order to obtain a better representation of aroma descriptors commonly used during wine tasting, also considering the aroma families proposed by Ferreira et al., (2010) [70]. The score attributed to each series was calculated as the sum of the average OAV of each volatile compound within that series (Table 4). ...
... This indicates that esters, and in particular the most potent ethyl hexanoate, ethyl octanoate and isoamyl acetate, could play a role in the aroma of Cluster 1 wines by a synergic and/or additive effect. These two first series, the fruity and the stewed apple/quince, may explain the fruity notes used by the panel to describe Cluster 1, considering that β-damascenone has been shown to enhance wine perceived fruitiness [70]. Table 3. Concentration (μg/L) of free volatile compounds in Cluster 1 and Cluster 2 wine samples. ...
... In fact, the aromatic series "vinous" and "fermentative" showed similar values. However, it is however possible that he descriptor "fermentative", characterizing Cluster 2, was not related to a higher concentration of some compounds, but to a lower content of compounds with a fruity character (esters, norisoprenoid), so that the generic fermentative character was more expressed in Cluster 2 [70]. ...
Lugana and Verdicchio are two Italian white wines with a Protected Designation of Origin (PDO) label. These two wine types are produced in different regions using the same grape variety. The aim of this work is to investigate the existence of volatile chemical markers that could help to elucidate differences between Lugana and Verdicchio wines both at chemical and sensory levels. Thirteen commercial wine samples were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS), and 76 volatile compounds were identified and quantified. Verdicchio and Lugana had been differentiated on the basis of 19 free and glycosidically bound compounds belonging to the chemical classes of terpenes, benzenoids, higher alcohols, C6 alcohols and norisoprenoids. Samples were assessed by means of a sorting task sensory analysis, resulting in two clusters formed. These results suggested the existence of 2 product types with specific sensory spaces that can be related, to a good extend, to Verdicchio and Lugana wines. Cluster 1 was composed of six wines, 4 of which were Lugana, while Cluster 2 was formed of 7 wines, 5 of which were Verdicchio. The first cluster was described as “fruity”, and “fresh/minty”, while the second as “fermentative” and “spicy”. An attempt was made to relate analytical and sensory data, the results showed that damascenone and the sum of 3 of esters the ethyl hexanoate, ethyl octanoate and isoamyl acetate, was characterizing Cluster 1. These results highlighted the primary importance of geographical origin to the volatile composition and perceived aroma of Lugana and Verdicchio wines.
... Despite the increased correlation of volatile compounds with HHW, aroma descriptors were not scored significantly higher (Table S2) or associated with HHW by PCA (Figure 2). This phenomenon could be because of aroma depressors, as defined by Ferreira (2010). The current study implied that the must composition had an overarching influence on the wine volatile composition which is overlaid with effects of winemaking and enzymatic activity (Unterkofler et al. 2020). ...
... It could be implied that HHW was lower in quality, based from previous modelling of wine quality on aroma profiles (Ferreira et al. 2009), but considering the number of attributes (Table S3) in which HHW did not significantly differ to that of LHW, MHW and Control wine, it is reiterated that the sensory profiles were not greatly different. The chemical parameters mostly responsible for wine sour taste, TA and pH, were comparable across treatment wines, therefore, the association determined by PCA between HHW and sour taste could be because of wine matrix interactions with flavour compounds that enhance sour taste in the case of HHW or suppress it in the case of LHW, MHW and Control wine (Ferreira 2010). Overall, the differences in sensory profile between LHW, MHW and the Control wine appeared minimal, and even at the higher grape heterogeneity level of HHW, the sensory scores were mostly similar statistically (Table S2). ...
Background and Aims
The wine industry widely acknowledges that grape heterogeneity exists throughout any given vineyard at the time of harvest. There is a lack of understanding, however, of the effects that heterogeneity has on wine composition and sensory qualities. This study compared the chemical composition and sensory attributes of wines produced using parcels of grapes with known heterogeneity.
Methods and Results
Cabernet Sauvignon berries were sorted into maturity classes using five density baths. Winemaking was undertaken with a varying proportion of sorted berries to obtain wines arising from low, moderate and high grape heterogeneity musts, containing the same level of TSS for comparison to a Control wine that represented the inherent heterogeneity of the harvested vines. Wines were distinguished by the concentration of 3‐isobutyl‐2‐methoxypyrazine, total anthocyanins and total phenolics, with the low heterogeneity wine having the highest values of each measurement. The high heterogeneity wine was characterised by a higher concentration of acetic acid. Principal component analysis of rate‐all‐that‐apply sensory attribute scores revealed that low and moderate heterogeneity wines were characterised by floral and pepper aroma attributes, and the high heterogeneity wine by sour taste.
Conclusions
The differing levels of grape heterogeneity had a subtle effect on Cabernet Sauvignon wine colour, aroma and taste attributes, but it was demonstrated that the level of grape heterogeneity could be of relevance if it translated into differences in wine quality and style.
Significance of the Study
The potential impact of grape heterogeneity on the chemical composition and sensory profile of Cabernet Sauvignon wine was highlighted.
... Odour activity values (OAV) were calculated as the ratio between the concentration of a compound and its perception threshold [18,19]. Theoretically, this value should be greater than the unity; however, due to synergic effects produced among different substances, those compounds with values greater than 0.2 can be considered as active aromas [20]. Nevertheless, we considered compounds with OAV > 0.5 for data analysis to be more conservative. ...
... Acetaldehyde, ethyl octanoate, 1-propanol, isovaleric acid, and ethyl hexanoate appeared at concentrations more than 20 times their respective odour thresholds. Other compounds (cis-3-hexen-1-ol, methionol, 2-phenylethyl acetate, and geraniol) showed OAV > 0.5 in some of the studied years and through synergic effects produced among different substances could be active aromas [20]. ...
Volatile composition plays a fundamental role in wine aroma and quality. However, the concentrations of volatiles depend on climate conditions and agricultural practices, such as irrigation. The aim of the current study was to assess the effects of irrigation on the volatile composition and sensory characteristics of wines from Vitis vinifera (L.) cultivar ‘Albariño’ in two zones of NW Spain (Rías Baixas and Ribeiro) during three consecutive years (2012, 2013, and 2014). Irrigation was scheduled by the vine grower in Rías Baixas, whereas it was fixed at 50% of the estimated crop evapotranspiration in Ribeiro. Water was applied in August, mainly, in Rías Baixas and from mid-July to mid-August in Ribeiro. Irrigation significantly altered the concentrations of several volatiles, which differed between zones and years. For instance, wines from the irrigated treatment had lower concentrations of isoamyl acetate, 2-phenylethyl acetate, and ethyl hexanoate than those from the rain-fed treatment in Rías Baixas. In contrast, irrigation increased the concentrations of ethyl hexanoate and ethyl octanoate, while reduced those of free terpenes in wines from Ribeiro. Mainly, these differences between zones were caused by the climate conditions of each region.
... Wine aroma is the product of a biochem-ical and technological sequence [8,9] resulting from the contribution of different volatile molecules deriving from grapes, fermentations, and reactions linked to aging, and sometimes oak and other woods. To date, more than 800 volatile compounds such as alcohols, esters, phenols, monoterpenes, norisoprenoids, lactones, aldehydes and ketones have been identified [10,11]. The majority of wine grapes are considered non-aromatic varieties in which many of the aroma metabolites that are key to wine aroma are present in various precursor forms, with grape variety, vineyard micro-climate and training deeply affecting their occurrence [12,13]. ...
... Concerning Corvinone, wines from cluster 1 all inoculated from Area 1, showed higher levels of norisoprenoids and eugenol (Figure 6), whereas wines of cluster 2 (Area 2 yeast 1 and 4) were characterized by low levels of acetic acid, below the odor threshold. Although these compounds were present in concentrations exceeding their odor threshold, at the levels at which they were detected they are not expected to specifically impart their odor to the wines of each cluster, but mostly to act synergistically to determine the overall sensory nuances perceived during tasting [11]. ...
Aroma profiles of withered Corvina and Corvinone wines from two different Valpolicella terroirs were investigated in relationship to yeast strain and use of spontaneous fermentation. The results indicated that volatile chemical differences between wines were mainly driven by grape origin, which was associated with distinctive compositional profiles. Wine content in terpenes, norisoprenoids, benzenoids and C6 alcohols, as well as some fermentative esters, were indeed significantly affected by grape origin. Conversely, yeast strain influence was mainly associated with fermentation-derived esters. Sensory analysis, besides confirming the major role of grape origin as driver of wine differentiation, indicated that spontaneous fermentations reduced the sensory differences associated with grape origin and variety, mainly due to high content of acetic acid and ethyl acetate.
... In order to do this, it seems useful to refer to the actual knowledge and understanding about the "aromatic structure" of table and sweet wines. Wines contain hundreds of volatiles among which 27, essentially originating from the alcoholic fermentation, are reported to be responsible for the "vinous" character common to all wines (Ferreira, 2010). This so called "wine aroma buffer" comprises ethanol together with fusel alcohols (isobutanol, isoamyl alcohol, hexanol, β-phenylethanol, methionol), organic acids (C2 to C10), isoacids and the corresponding esters (isobutyric-, 2-methyl butyric-, isovaleric-), ethyl esters (ethyl acetate to decanoate), acetates (isobutyl-, isoamyl-, βphenylethyl-) and carbonyl compounds (diacetyl, acetaldehyde). ...
... The aroma of sweet wines can be exemplified in three main parts: volatiles linked to grapes dehydration (γand δ-lactones, furans); varietal aromas more or less preserved depending on the dehydration conditions (terpenes, norisoprenoids); volatiles produced during the alcoholic fermentation in special conditions, such as high sugar levels in the must, responsible for slow fermentation rates (ethylic esters and acetates, fusel alcohols, fatty acids, phenylpropanoids, high concentrations of acetic acid, ethyl acetate, acetaldehyde and diacetyl) (Moio & Piombino, 2013;Piombino et al., 2010;Reboredo-Rodríguez, González-Barreiro, Rial-Otero, Cancho-Grande, & Simal-Gándara, 2015). According to the literature (Ferreira, 2010 and references therein) some of these volatiles (e.g. linalool and isoamyl acetate, both detected in the wines of this study), can impact the aroma of some specialized wines such as sweet wines. ...
In this study a Retronasal Aroma Simulator was employed to compare the release of volatiles from two different white wine matrices (TW: table, SW: sweet) with and without the addition of human or artificial saliva to simulate retronasal and orthonasal conditions, respectively. The headspace volatiles were isolated by Solid Phase Microextraction under dynamic conditions and identified and quantified by Gas-Chromatographic analyses. Compared to the orthonasal, the retronasal conditions modified the release of odorants from both wines and the observed trends cannot be ascribed only to dilution consequent to saliva addition. The relative amounts of volatiles belonging to different chemical classes were modified in the presence of saliva with possible sensory implications concerning some fruity (esters), oxidative (furans) and varietal (linalool, vitispirane) odorants. Regression analyses show that the impact of saliva depends on the volatile (concentration and hydrophobicity) and the non-volatile (residual sugars) composition of the wine. The highly significant linear models (TW: R² = 0.988; SW: R² = 0.993) indicate that the release of volatiles is logP octanol/water dependent in both the wines but the slopes change with matrix composition. This suggest that in the presence of human saliva the release of odorants with similar hydrophobicity vary as a linear function of their initial headspace concentration above the wine and is modulated by the composition of the wine matrix. Differences between artificial and human saliva confirmed that the retronasal release of wine odorants is affected by the whole salivary composition and suggest that salivary components different from mucin and α-amylase are involved in the retention of the most hydrophobic volatiles as well as in the metabolization of some aromas.
... The number of key odourants is relatively small ranging from 3 to 40 for each food (Dunkel et al., 2014). This model is consistent with the perceptual flavour wine model described by Ferreira (2010). According to this concept, the aroma of wine is characterised by a few molecules (about 30) that act as a buffer (the "aroma base") because differences in their concentrations are not reflected in different aromatic perceptions. ...
... Examples of impact volatiles are terpenes in varieties like Muscat or off-flavours. In the absence of impact molecules, wines may be described as odourless and different varietals are then indistinguishable (Campo et al., 2008) and have a light, sweet, pungent, alcoholic, and somewhat fruity aroma (Ferreira, 2010). ...
The tasting methods in wines have long been used for many diversified purposes related to sensory research, wine quality, or consumer studies. Recent advancements in neuroscience have explained how sensory perception is processed justifying the adaptation of methods to meet the functions of neuronal mechanisms. In particular, the implications of the emotional nature of olfaction in wine description and appreciation have not been taken into account properly by most common tasting approaches.
The purpose of the present chapter is to present a critical appraisal of current tasting methods with a focus on those most frequently applied at the winery and consumer levels. The limitations will be explained and improvements will be proposed together with an alternative method gathering emotional and sensory responses. Moreover, the issue of fine wine evaluation will be addressed regarding the synthetic properties that distinguish these wines from their international commercial counterparts.
A holistic approach to wine tasting would benefit from the inputs of scholars with backgrounds in philosophy, psychology, or economy. Hopefully, mutual understanding among wine professionals, researchers, and consumers would be facilitated by changing the paradigm of wine tasting methodologies.
... The number of key odourants is relatively small ranging from 3 to 40 for each food (Dunkel et al., 2014). This model is consistent with the perceptual flavour wine model described by Ferreira (2010). According to this concept, the aroma of wine is characterised by a few molecules (about 30) that act as a buffer (the "aroma base") because differences in their concentrations are not reflected in different aromatic perceptions. ...
... Examples of impact volatiles are terpenes in varieties like Muscat or off-flavours. In the absence of impact molecules, wines may be described as odourless and different varietals are then indistinguishable (Campo et al., 2008) and have a light, sweet, pungent, alcoholic, and somewhat fruity aroma (Ferreira, 2010). ...
Background
Wine flavour has been methodically studied since the beginning of sensory research, with various purposes relating to product quality and consumer preferences. Recent advances in neuroscience have provided a deeper insight into how the perceptions elicited by flavour-active molecules are processed by the brain. In particular, the implications of the synthetic, emotional and mental imagery features of olfaction, together with the cross-modal influences on flavour perception, should be properly acknowledged in tasting methods.
Scope and approach
The purpose of this review is to present a critical appraisal of current tasting methods, with focus on those that are most frequently applied to assess fine wine. The remarkable ability to distinguish odours, and the emotional nature of the sense of smell, are the basis for the development of alternative tasting approaches that have lead to recent advances. The limitations of aroma and flavour descriptive analysis resulting from the synthetic nature of olfaction will be discussed and, in particular, those limitations that relate to the holistic evaluation of quality that constitutes the core of aesthetic judgements.
Key findings and conclusions
We argue that the conventional tasting sequence and the dominance given to descriptive analysis contributes to the subordination of the holistic nature of wine assessment. Further, expert quality judgements may be strongly biased by cognitive factors and wine preferences. Hence, the highest level of expertise may be attained when individuals are able to recognise a fine wine's synthetic properties (e.g. complexity, harmony, persistence) in association with socio-cultural aspects (e.g. origin, winemaking traditions), and then produce aesthetic judgements independently from wine enjoyment.
Overall, fine wines may be defined as those characterized by superior synthetic or holistic properties that are perceived and appreciated by individuals who understand, and in the context of, their cultural meaning.
... From these, the aroma is considered one of the most significant factors to establish wine quality and character and, therefore, for determining consumers' acceptance. A relationship between wine character and its volatile composition is recognized by several researchers worldwide, and hundreds of volatile compounds belonging to different chemical classes, namely alcohols, esters, acids, aldehydes, ketones, lactones, terpenoids, and volatile phenols, have already been identified in different wine varieties [3][4][5][6][7][8][9]. As these compounds produce an effect on consumers' sensory perceptions, both volatile composition and sensory properties are essential to determine wine aroma characteristics. ...
Wine aroma is the result of complex interactions between volatile compounds and non-volatile ones and individual perception phenomenon. In this work, an aroma network approach, that links volatile composition (chromatographic data) with its corresponding aroma descriptors was used to explain the wine aroma properties. This concept was applied to six monovarietal wines from Bairrada Appellation (Portugal) and used as a case study. A comprehensive determination of the wines’ volatile composition was done (71 variables, i.e., volatile components), establishing a workflow that combines extraction techniques and gas chromatographic analysis. Then, a bipartite network-based approach consisting of two different nodes was built, one with 19 aroma descriptors, and the other with the corresponding volatile compound(s). To construct the aroma networks, the odor active values were calculated for each determined compound and combined with the bipartite network. Finally, the aroma network of each wine was compared with sensory descriptive analysis. The analysis of the specific aroma network of each wine revealed that Sauvignon Blanc and Arinto white wines present higher fruity (esters) and sweet notes (esters and C13 norisoprenoids) than Bical wine. Sauvignon Blanc also exhibits higher toasted aromas (thiols) while Arinto and Bical wines exhibit higher flowery (C13 norisoprenoids) and herbaceous notes (thiols), respectively. For red wines, sweet fruit aromas are the most abundant, especially for Touriga Nacional. Castelão and Touriga Nacional wines also present toasted aromas (thiols). Baga and Castelão wines also exhibit fusel/alcohol notes (alcohols). The proposed approach establishes a chemical aroma fingerprint (aroma ID) for each type of wine, which may be further used to estimate wine aroma characteristics by projection of the volatile composition on the aroma network.
... The level of integration would be high enough so that the specific aroma nuances of individual components would be difficult to perceive. The concept of aroma vector, even if implicitly used in previous works, has been just recently defined (Ferreira, de-la-Fuente-Blanco, & Sáenz-Navajas, 2019) as "a perceptual unit constituted by one or several molecules with similar aroma descriptors, which altogether and in an integrated form, are responsible for a specific set of sensory features of a type of products" and is meant to be a basic concept for modelling aroma perception. ...
Aroma contribution of individual esters has been studied in complex mixtures mimicking red wine models. A mixture containing 14 ethyl esters at concentrations found in wine (V1) was prepared and kept as reference. Isointense and qualitatively similar aroma vectors with a reduced number of esters (V2-V7) were prepared. Those vectors were introduced in two reconstituted wines to assess whether simpler vectors could replace V1 without compromising wine quality. In the simpler young wine model, V1 could be replaced by a vector containing just 3 odorants (ethyl 2-methylbutyrate, ethyl butyrate and hexanoate). In the oaky model, a vector containing just ethyl 2-methylbutyrate (V7) could replace V1 without any discernible sensory change. Results also reveal that sub- or perithreshold odorants play outstanding roles on the overall odour intensity of the mixture and that aroma simplification concomitantly implies an increase in the amount of odorant required to keep the intensity of the aroma vector.
... This indicator is the ratio between the concentration of an individual compound and its perception threshold [33,34]. Theoretically, this value should be greater than one; however, due to synergic effects among different substances, those compounds with values greater than 0.2 can be active aromas [35]. Nevertheless, we used those compounds with an OAV > 0.5 for data analysis. ...
Adopting cover crops for vineyard soil management can provide several benefits, including soil protection, reductions in vine vigor, and enhancements in berry composition. However, the effects of this practice on wine aroma have seldom been addressed. This study aimed to determine the influence of different cover crops and soil tillage on the must and wine amino acid composition and wine volatile compounds of the red cultivar, 'Mencía' (Vitis vinifera L.), grown in Northwest Spain. Treatments consisted of soil tillage (ST), native vegetation (NV), English ryegrass (ER), and subterranean clover (SC). Cover crops did not alter the macro-constituents of musts; however, musts from NV and SC tended to lower concentrations of amino acids. Some color attributes of wines were influenced by cover crops in the vineyard. Methanol and trans-linalool oxide (pyran) concentrations in wines were significantly affected by soil management. Professional tasters encountered differences in visual, aroma, and palate descriptors of wines depending on the treatment imposed in the vineyard. These alterations in sensory properties seemed to obey to slight modifications of wine chemical characteristics due to vineyard soil management. According to these results, cover crops might be useful for modulating wine aroma in humid climates.
... The quantitative composition is in agreement with previous studies for neutral white wines as reported by Rapp (1992) and Guth (1997). As shown by Ferreira (2010) and Escudero et al. (2004), the personal impression of the aroma in neutral white wines such as 'Pinot blanc' is more influenced by the interaction of the appropriate amounts of many different volatile substances than by the single concentration of a key compound. However, for 'Pinot blanc' wines, no general-impact compound has been identified so far. ...
Several certified 'Pinot blanc' clones available at a local market were evaluated under specific viticultural conditions. Small but relevant differences in agronomic behaviour could be recognized. Clones A9-1, Fr74, H31 and N81 showed higher yield, while clones Lb16 and 18, Fr70 and 74 and N81 reached higher berry sugar contents. Clone Fr74 showed the most vigorous growth. Clones Fr70 and Dreher209 produced wines with the highest quality ratings. Analysis of essential aroma compounds by HS-SPME-GC-SIM-MS reveals that the clone Dreher209 is characterized by high values of terpenes and floral aroma. Pear-specific odour activity values (OAVpear) presented as sensorial-analytical typograms were calculated from the analysed concentrations of eight esters in clones. The overall OAVpear of the wines ranged from 37.5 (H31, 2016) to 84.3 (N81, 2017). The largest contributors to the pear OAV were the impressions for “exotic pear candy” and “oily waxy pear-like”. The sum of OAV “fresh pear” and “overripe pear” ranged from 6.9 (H31, 2016) to 16.1 (N81, 2017). However, an influence of vintage on the sensorial descriptors “overripe pear” and “OAV pear” was determined. A positive correlation between sugar content °Babo KMW and the descriptors for “fresh pear” and “overripe pear” is likely. Thus, clone H31 showed the lowest sugar content and lowest OAV fresh pear and OAV overripe pear content. The genetic variability was estimated by applying fingerprints with simple sequence repeat (SSR), inter-SSR and single-nucleotide polymorphism (SNP) markers. The certified clones are characterized by less variability compared with some other candidate genotypes involved in this study. No stable differences could be found in A9-1, A9-3, A9-4, C311, Fr70, or N81. That means that the clones investigated do not cover the broader genetic base of the cultivar, and that some of these clones are almost identical.
... Nach der "spanischen Aromalehre" zählen die Verbindungen Ethylhexanoat, Ethyloctanoat, Ethyldecanoat sowie Isoamylacetat neben Ethanol, Diacetyl, Acetaldehyd, Isobutanol, Isoamylalkohol, Hexanol, ß-Phenylethanol, Methionol, Essigsäure, Butt ersäure, Hexansäure, Octansäure, Decansäure, Isobutt ersäure, Isovaleriansäure, 2-Methylbutt ersäure, Ethylacetat, Ethylbutyrat, Isobutylacetat, ß-Phenylethylacetat, Ehtylisobutyrate, Ethyl 2-methyl butyrate und Ethylisobutyrate zu den Grundaromen der Weinmatrix. Deren Zusammenspiel ist für den "weinähnlichen" Charakter verantwortlich (Ferreira et al., 2010). Die Mischung aus diesen 27 Verbindungen bildet einen sogenannten "Aroma-Puff er". ...
Pear aroma is described as particularly typical of Austrian Pinot blanc wines. It is associated with volatile ester compounds like ethyl trans2-cis4-decadienoate,
methyl trans-geranoate, isoamyl acetate, isoamyl octanoate, ethyl octanoate, ethyl hexanoate, ethyl decanoate and ethyl dodecanoate. In the course of this study, the technological influencing factors skin contact, yeast selection, fermentation
temperature and yeast contact (sur lie) as well as the influence of the grape material on the content of the main pear aromas are studied. For this purpose, three experiments were conducted with Pinot Blanc grapes from two different vineyards and two vintages. The microvinified wines were then analyzed by means of HS-SPME-GC-SIM-MS
and evaluated for the perceived pear aroma using a trained panel. With respect to the analytical results, so-called "sensory-analytical typograms" were calculated. Using non-parametric tests influencing factors were tested for their significance. For the perceived pear aroma the most important influencing factor is the grape material. In mature vintages
such as 2015, the content of the key volatile substances is higher than in unripe vintages. Significant influences on the content of ethyl esters and thus the sensory-analytical typograms may be a short yeast contact after fermentation. It was also found that the cooler fermentation significantly altered the sensory-analytical typograms, but the resulting wines were described with less pear aromatics in the sensory review. The yeast significantly influenced the content of individual ester compounds. However the time of skin contact had no influence on the pear aroma.
... In order to estimate the influence of each volatile on the Treixadura wine aroma, odor activity values (OAV) were computed as the ratio between the concentration of a given compound and its corresponding perception threshold [29]. Theoretically, OAV should be greater than the unity [29]; however, due to synergic effects among different substances, those compounds with values greater than 0.2 can be considered as active aromas [30]. The odor thresholds for the compounds considered in this study, along with their corresponding aromatic descriptors, are shown in Table 1. ...
Aroma is a crucial attribute for wine quality, particularly in white wines. Traditionally, the consumption of young white wines is recommended over the year following grape harvest due to potential aroma losses that would worsen wine quality. This study aimed to investigate the evolution of volatile compounds, odor activity value-based aroma notes, and sensory perception in Treixadura (Vitis vinifera L.) dry white wines during a 24-month bottle-aging period. Volatile composition was determined by gas chromatography, and wine sensory evaluation was performed by experts. Wine samples had similar volatile compositions at the time of bottling. The volatile contents of the wines were respectively 322.9, 302.7, 323.0, and 280.9 mg L −1 after 6, 12, 18, and 24 months of bottle storage. Most of the volatiles tended to maintain constant concentrations, or with slight increases in all families of volatiles except for acetates and carbonyl compounds, until two years after harvest (18 months of bottle storage) and, then, concentrations reduced sharply. After 24 months of storage in the bottle, the concentrations of terpenes, C6 compounds, higher alcohols, ethyl esters, fatty acids, acetates, carbonyl compounds, and volatile phenols were reduced by 32%, 47%, 11%, 39%, 50%, 74%, 41%, and 54%, respectively. The 18-month bottle-aged wines showed the highest concentrations of volatiles, as well as the best performance in the sensory evaluation, suggesting that a good balance of the aroma attributes was achieved on this date. In conclusion, the current study suggests that Treixadura wines expressed their maximum aroma potential two years after grape harvest.
... There is a large amount of work previously conducted with regard to the effects of nutrient addition on sensory of fermented beverages. Multiple studies have found an increase in fruitiness after adding nutrients [36,37], which is most likely influenced by the composition of the starting material. These studies also showed an increase in other characteristics (floral and citrus aromas) presumably due to nutrient addition. ...
Honey wine, also known as mead is made from honey, water and yeast. This beverage has experienced resurgence in popularity but to be competitive producers must consistently produce high quality products. This study focused on the effect of three fermentation temperatures and four different nutrient addition schedules on mead quality and fermentation parameters. Basic mead chemistry parameters were measured. Aroma composition was determined using HS-SPME-GCMS and descriptive analysis was used to determine the sensory differences of the meads. Significant differences were found for treatments receiving nutrients versus those receiving no nutrients. Aroma composition showed significant differences based on fermentation temperature and nutrient schedule. In particular, the coolest fermentation temperature resulted in meads with greater amounts of esters. However, despite the fact that a significant difference in aroma composition was found these do not result in any large sensory differences, particularly for those ferments with nutrient additions. Only the control was significantly different from the other treatments based on sensory data, although certain trends were found based on fermentation temperature and nutrient addition schedule. These results show that mead makers can use nutrient schedules and fermentation temperature to not only significantly reduce time-to-market but also to potentially achieve sensory goals. Additional work is required to determine whether nutrient blends tailored to particular implementations can be applied using commonly-accepted nutrient schedules.
... Linalool is always been the compound of attraction for food and beverages [3], antimicrobial activity [4], antibacterial activity [5], etc. It is majorly used in alcohol industries for flavoring in combination with other mono-terpenes [6]. Linalool and citronellal are registered as food additives for direct addition to food for human consumption [7]. ...
Environmental benign approach for extraction of essential oil was made. An essential oil rich in citronellol, linalool and citronellal was extracted from the leaves of Cymbopogon winterianus using a clean hybrid extraction technique, sono hydrodistillation. Sono hydrodistillation combines ultrasonic waves along with conventional hydrodistillation process to have symbiotic outcomes in terms of process improvement. Significant process parameters such as size of the plant material, extraction time, power, ultrasound amplitude, pulse interval and solid loading were investigated independently to study the effect on yield of oil and composition of oil. The water residue remained after extraction of volatile oil was analyzed using Folin-Ciocalteu method to determine the total phenolic content (TPC) which would help in assessing the residue as a useful by-product. Substantial reduction in time was observed with the inclusion of ultrasound compared to conventional hydrodistillation. Further, to optimize the extraction conditions, observe interactive effects of various parameters and develop mathematical model, response surface methodology was employed. The maximum yield of oil was found to be 4.118% (w/w) at 21 min extraction time, 5 g solid loading, 250 mL water volume, 500 W heating mantle power, 70% ultrasonic amplitude and 10:50 pulse interval. Total phenolic content was 13.84 mg GAE/g DM. The citronella oil was found to be composed of 27.47% of linalool, 11.52% of citronellal, 34.25% citronellol and 11.15% of elemol. Extraction time, solid loading and pulse interval had the significant influence on the yield of oil and total phenolic contents. Microscopic analysis has assisted in envisaging the probable mechanism indicating the role of sonication for rapid extraction. This novel technique was compared with the conventional hydrodistillation to ascertain the impact towards process intensification. Sono hydrodistillation was found to be a greener and cleaner process as energy consumption has been reduced by 40% while carbon footprint has shrunken by 47%.
... Of the many classes of volatile compounds found in hops, the class of terpenoids, which includes terpenes, sesquiterpenes, and their related alcohols, makes up the largest percentage of hop essential oil (13). The aroma profile of complex products, such as beer, is the result of not just one compound or class but rather the interactions between them (15). Nonetheless, terpenoids represent an important class of compounds that contribute diverse aromas to beer ranging from floral, citrusy, and fruity to woody, green, herbal, and pine (1,37,40). ...
Recently, brewers have dramatically increased the complexity and intensity of aromas in hop-forward beers by using diverse hopping regimes. For this study, the terpenoid content and sensory attributes of beers made using different hop additions were measured. Beers were brewed while varying two factors: hop cultivar (Simcoe and Hallertau Mittelfrüh) and timing of hop addition (60 min boil, 25 min whirlpool, or 48 h dry hopping). Additionally, the impact of yeast strain on treatment was investigated. Each treatment was compared with an unhopped control using stir-bar sorptive extraction GC-MS and descriptive sensory analysis. Multivariate statistical analysis showed relationships between instrumental and sensory techniques. Whirlpool additions produced beers with the highest concentrations of geraniol, linalool, and β-citronellol; beers brewed with highly aromatic Simcoe hops produced more intense and individually distinct aromas for each hopping regime compared with the Hallertau Mittelfrüh hopped beers. Conversely, beers brewed with Hallertau Mittelfrüh hops showed less intense aromas with less distinction between hopping regimes, except for the dry-hopped treatment, which was characterized by a more floral type of aroma than the other Hallertau Mittelfrüh treatments. This research shows that despite the popularity of dry hopping as an aroma hopping method, whirlpool additions can produce more intensely aromatic beers.
... Sensory analysis can be used to evoke, measure, analyse, and interpret the reactions to stimuli perceived through the senses. Sensory analysis still remains an efficient tool for assessing the properties of sparkling wine (Ferreira 2010). The results of the sensory analysis of sparkling wines are shown in Figure 1. ...
Miličević B., Babić J., Ačkar Đ., Miličević R., Jozinović A., Jukić H., Babić V., Šubarić D. (2017): Sparkling wine production by immobilised yeast fermentation. Czech J. Food Sci., 35: 171–179. The prospects of sparkling wine production by the 'Champenoise' method using alginate-immobilised yeast cells were examined. Grape varieties dominant in quantity were selected within the group of recommended and permitted varieties of Kutjevo vineyards, located in the eastern part of continental Croatia. Research revealed that there are no influential variations in the principal physicochemical and sensory characteristics between sparkling wines obtained through immobilised yeast and traditional sparkling method. The analysis of aroma compounds showed minor differences between samples. Observed oenological parameters assessed in the final products did not show any relevant oenological differences, with the exception of alcohol content, which was slightly higher in sparkling wines made with yeast cells immobilised with calcium alginate beads. According to this research, the sensory properties of the produced sparkling wines, compared to sparkling wine produced with free yeast, did not show any significant differences. On the full-scale obtained results indicate that some of the selected varieties can be sorted as suitable for the production of sparkling wine using immobilised yeast cells.
... Aroma compounds contribute to a large extent to the organoleptic characteristics and typicity of wine. Slight differences in the concentrations of these volatile molecules create diverse wine aroma profiles [1,2]. Wine aromas can be classified into three main groups according to their origin: "varietal" aromas specific for grape varieties, "winemaking" aromas produced during the fermentations and "mature" aromas developed during aging [3]. ...
Background
Volatile thiols largely contribute to the organoleptic characteristics and typicity of Sauvignon blanc wines. Among this family of odorous compounds, 3-sulfanylhexan-1-ol (3SH) and 4-methyl-4-sulfanylpentan-2-one (4MSP) have a major impact on wine flavor. These thiols are formed during alcoholic fermentation by the yeast from odorless, non-volatile precursors found in the berries and the must. The present study investigates the effects of vine nitrogen (N) status on 3SH and 4MSP content in Sauvignon blanc wine and on the glutathionylated and cysteinylated precursors of 3SH (Glut-3SH and Cys-3SH) in the berries and the must. This is paralleled by a RNA-seq analysis of gene expression in the berries. The impact of N supply on the expression of the glutathione-S-transferase 3 and 4 (VviGST3 and VviGST4) and the γ-glutamyltranspeptidase (VviGGT), considered as key genes in their biosynthesis, was also evaluated. ResultsN supply (N100 treatment) increased the 3SH content in wine while no effect was noticed on 4MSP level. Furthermore, N supply increased Glut-3SH levels in grape berries at late berry ripening stages, and this effect was highly significant in must at harvest. No significant effect of N addition was noticed on Cys-3SH concentration. The transcript abundance of the glutathione-S-transferases VviGST3 and VviGST4 and the γ-glutamyltranspeptidase (VviGGT), were similar between the control and the N100 treatment. New candidate genes which might be implicated in the biosynthetic pathway of 3SH precursors were identified by whole transcriptome shotgun sequencing (RNA-seq). Conclusions
High vine N status has a positive effect on 3SH content in wine through an increase of Glut-3SH levels in grape berries and must. Candidate GSTs and glutathione-S-conjugates type transporters involved in this stimulation were identified by RNA-seq analysis.
... Aroma compounds contribute to a large extent to the organoleptic characteristics and typicity of wine. Slight differences in the concentrations of these volatile molecules create diverse wine aroma profiles [1,2]. Wine aromas can be classified into three main groups according to their origin: "varietal" aromas specific for grape varieties, "winemaking" aromas produced during the fermentations and "mature" aromas developed during aging [3]. ...
... This result was consistent with aroma analyses, as only 25% of the tested aromatic molecules showed a change in concentration with fermentation temperature (most of them were higher at 19°C than at 15°C), and the concentrations of 13 of these 24 molecules were below the sensory threshold. Additionally, the "aroma-buffer effect" (Ferreira 2010), which is exerted by a complex mixture (as wine) and counteracts the sensory effect of changes in a few odorant molecules, may also explain why the panel did not distinguish the wines even though the aromatic profile was slightly different. ...
Heat removal accounts for ~90% of the total energy requirements of the winery and is mostly related to the temperature control of the wine tanks used for fermentation and maturation. The aim of this work was to evaluate the effects of a selected wine yeast, chosen to optimize sensory characteristics and minimize SO2 production at temperatures higher than the standard for winemaking, on energy consumption during the fermentation process of the Franciacorta base wine. Fermentations using the new yeast strain were conducted at 15 and 19°C, and energy consumption was compared. Moreover, the sensory, chemical, and aromatic features of the Franciacorta sparkling base wines were measured. Fermentation required 21.6 Wh/Lgrape must at 15°C and 7.7 Wh/Lgrape must at 19°C, reducing energy use by ~65% at the higher temperature. Use of the tested yeast had positive effects on energy saving during fermentation without compromising sensory, chemical, and aromatic profiles of the resulting wine. This work suggests possible methods for wineries to adopt a more sustainable winemaking process that lowers energy consumption and decreases SO2 content in wines, which may introduce eco-labeling strategies and price-premium policies.
... These molecules are like the different characters in a book: individually they can be associated with specific features, but when interacting they can build a story. In short, the aroma of a wine can help us to detect not only the wine faults (Chatonnet et al., 2004;Mayr et al., 2015), but also to identify the grape cultivar, region, country or even some of the winemaking techniques employed in the process (Ferreira, 2010). Some of these compounds are strongly associated with certain wines, such as rotundone and the black pepper smell in Australian Shiraz (Siebert et al., 2008), and the presence of certain lactones in dessert wines (Stamatopoulos et al., 2015). ...
Over the years, Pinotage has found its way into the South African and international market. Producers have used the flavour potential of this "original" South African grape to produce different wine styles, one of them being the so-called "coffee-style Pinotage". The current study aims to explain the impact of furanmethanethiol (FMT) on the characteristic coffee aroma of these coffee-style wines. Chemical and sensory evaluation, as well as data mining of the technical information available, was performed. Not all wines marketed as "coffee Pinotage" showed a high "coffee" rating. However, the results showed a good correlation between the aroma perception and FMT concentrations (R 2 = 0.81). However, RV coefficients were low when comparing the coffee rating with the information provided on both the front and the back label, which shows that, in some cases, the use of the "coffee Pinotage" term was rather part of the marketing strategy.
... Furthermore, the OTVs obtained, generally determined by sensory panel, can di er among individuals. Certain assessors can be very sensitive or not sensitive at all (anosmic) to the aroma of a particular compound (Ferreira, 2010). Additionally, no synergistic or antagonistic e ects are considered when studying an entire aroma pro le, which could lead to an under-or over-estimation of the odor activity of a compound. ...
Roasting plays a critical role in the production process of cocoa liquor and chocolate. Besides desirable changes in color and moisture content, flavor development is one of the most important reasons to roast cocoa. By means of a convective and/or conductive heat transfer, cocoa and nutty flavors are generated within the roasted beans, while the bitter taste and astringent mouthfeel are reduced. Roasting via a convective and/or conductive heat transfer is easy applicable and therefore also commonly used. However, these roasting techniques are lately questioned due to the long roasting times needed to sufficiently heat the core of the beans. Therefore, a growing interest is encountered to search for optimal roasting conditions and/or alternative roasting techniques, with the development of a desirable flavor profile as primary criterion. Within this research a comparison was made between conventional and microwave-assisted roasting with the main focus on flavor. The impact of varying roasting conditions (i.e. time, temperature and power input) on the flavor profile of cocoa liquor and chocolate was investigated via both instrumental (i.e. HS-SPME-GC-MS, UPLC-HRMS) and sensory (i.e. trained panel, consumer panel) techniques. Results confirmed that microwave-assisted roasting has the potential to be used as alternative technique.
... In the case of isoamyl acetate, below 0.02 mg/L, this compound is just one of the many sweet-fruity compounds with a very weak sensory effect. Between 0.2 and 1.4 mg/L, the importance of isoamyl acetate grows to the point that it becomes an important contributor to the fruity note [33]. ...
Grape-based brandies are one of the most popular alcoholic beverages in the world. The most popular one, Cognac, comes from the Charentes region of Southwest France, and it is mostly produced from the grape variety ‘Ugni Blanc’. However, wines destined for the elaboration of wine spirits also come from different white grape varieties; ‘Colombard’, ‘Folle Blanche’, ‘Montils’, and ‘Semillon’. In this study, the possibility of using the red grape varieties ‘Cabernet Sauvignon’ and ‘Syrah’ was investigated with an emphasis on the change of volatile compounds during the production process. During production, some specific volatile compounds such as 2-hexenal, 3-octanone, isopropyl myristate, ethyl palmitate, ethyl oleate, phenethyl acetate, 1-hexanol, and β-damascenone could be attributed to the primary aroma generated from the grape varieties. During the vinification and fermentation process, the development of ethyl hexanoate, ethyl octanoate, 3-methylbutanol, acetic acid, and octanoic acid occurred. Finally, 3-methylbutanol and predominant esters, ethyl hexanoate, ethyl octanoate, ethyl decanoate, and ethyl laurate, were generated during the distillation and maturation process. The composition and concentration of determined predominant esters in produced brandies suggest that both brandies have volatile profiles comparable to some of the world’s most popular brandies.
... Wine aroma arises from a complex combination of chemical and biochemical transformations taking place during wine production. Depending on their concentration, only a portion of the more than 800 volatile identified compounds is actually contributing to wine perceived aroma (Ferreira, 2010). Many of these compounds, in particular terpenoids and norisoprenoids, originate in the grape, and in the majority of the Vitis vinifera varieties they occur mostly in the form of non-volatile, odourless precursors (Crupi et al., 2020;Parker, Capone, Francis, & Herderich, 2018). ...
Volatile composition and sensory properties of Corvina and Corvinone red wines in relationship to grape origin, yeast strain and inoculated vs. spontaneous fermentation were investigated. Experimental wines were produced using freshly harvested grapes of the two varieties coming from two different areas. The results indicated that, by affecting grape composition, grape origin had a primary impact on wine aroma chemical and sensory properties. From a chemical point of view, this effect was associated not only with grape-derived compounds but also to some extent with fermentation-derived esters. Yeast strains influence was mostly associated with higher alcohols and certain esters, whereas the main characteristic of spontaneous fermentation was increased concentration of ethyl acetate. Sensory analysis confirmed the greater impact of grape origin compared to yeast strain, indicating clusters of odor similarities which were mostly associated with variations in the content of ethyl esters, C6 alcohols, and norisoprenoids in Corvina and of norisoprenoids, cyclic terpenes, acetate esters, and ethyl acetate in Corvinone, respectively.
... Furthermore, the OTVs obtained, generally determined by sensory panel, can differ among individuals. Certain assessors can be very sensitive or not sensitive at all (anosmic) to the aroma of a particular compound (Ferreira 2010). Additionally, no synergistic or antagonistic effects are considered when studying an entire aroma profile, which could lead to an under-or over-estimation of the odor activity of Figure 2. Schematic diagram showing discrepancy of the assumed linear model (blue) and potential relation (red) between chemical concentration (x-axis) and sensory intensity (y-axis) (Chambers and Koppel, 2013). ...
ABSTARCT
The performance of appropriate instrumental and/or sensory analyses is essential to gain insights into the flavor profile of cocoa products. This three-part review is compiled of an overview of the most commonly used instrumental techniques to study cocoa liquor and chocolate flavor, their perception by a trained panel and the potential relationship between them. Each part is the result of a thorough literature study, principally focusing on the assumptions, features and limitations of these techniques. Reviewing of the literature revealed that cocoa matrix effects and methodology restraints were not always considered when instrumentally analyzing cocoa flavor. With respect to sensory analyses, various studies lacked reporting of accomplished trainings and performance of panelists. Moreover, a discrepancy was noticed in the descriptive flavor lexicon employed. Finally, when linking instrumental and sensory data, linear modeling is regularly applied, which might not always be appropriate. This review paper addresses the challenges associated with flavor assessment, intending to incite researchers to critically study cocoa flavor and apply standardized protocols and procedures.
... Different chemical classes of VOCs (i.e., ketones, volatile acids, terpenes, alcohols, esters, aldehydes, etc.) have been detected in wine from postharvest dehydrated grapes as a function of water loss technique, grape variety, pedoclimatic conditions, winemaking practices, and fermentation, but the overall knowledge of the mechanism for wine flavor development is still lacking. Wine contains numerous VOCs actually, but most of them are not able to create individually a sensory impact as they are at concentrations well below their sensory threshold; wine aroma is determined by the interactions among many VOCs, and its complexity depends on the concentration of particular chemicals and on the presence of other aroma compounds, which can act synergistically or antagonistically, modifying or adding more aroma nuances [105]. ...
In postharvest science, water loss is always considered a negative factor threatening fruit and vegetable quality, but in the wine field, this physical process is employed to provide high-quality wine, such as Amarone and Passito wines. The main reason for this is the significant metabolic changes occurring during wine grape water loss, changes that are highly dependent on the specific water loss rate and level, as well as the ambient conditions under which grapes are kept to achieve dehydration. In this review, hints on the main techniques used to induce postharvest wine grape water loss and information on the most important metabolic changes occurring in grape berries during water loss are reported. The quality of wines produced from dried/dehydrated/withered grapes is also discussed, together with an update on the application of innovative non-destructive techniques in the wine sector. A wide survey of the scientific papers published all over the world on the topic has been carried out.
... Organoleptic characteristics of wine is the result of interactions of several compounds. The knowledge of these compounds are important factors in assessing the quality of wine [33,34]. ...
The paper would like to show a direct injection into GC-MS/QqQ for the determination of secondary aromas in white wine samples fermented in two different ways. The procedure has been compared with more traditional methods used in this field, i.e., headspace analysis and liquid–liquid extraction. The application of such direct injection, for the first time in the literature, allows us to analyze Volatile Organic Compounds (VOCs) in the range 0.1–100 µg mL−1, with Limits of Detection (LODs) and Limits of Quantification (LOQs) between 0.01–0.05 µg mL−1 and 0.03–0.09 µg mL−1, respectively, intraday and interday below 5.6% and 8.5%, respectively, and recoveries above 92% at two different fortification levels. The procedure has been applied to real wine samples: it evidences how the fermentation in wood (cherry) barrel yields higher VOC levels than ones in wine fermented in steel tank, causing production of different secondary aromas and different relative flavors.
... 50 However, the contribution of each independent odorant compound to the aroma of 51 an alcoholic beverage can also be influenced by the contribution of other volatile com-52 pounds detected, producing a typical aroma of the beverage. 56 Nf: not found -*Calculated using the mean ODT value. Principal component analysis (PCA) was conducted to interpret the relationship between the microbiological, chemical and volatile compositions of the different fermented samples and identify the main components that best discriminate between the samples analyzed. ...
The aim of this work was to study the production of kefir-like beverage by fed-batch fermentation of red table grape juice at initial pHs of 3.99 (fermentation A) and 5.99 (fermentation B) with kefir grains during four repeated 24-h fed-batch subcultures. However, all kefir-like beverages (KLB) were characterized by low alcoholic grade (≤ 3.6%, v/v) and lactic and acetic acid concentrations. The beverages obtained from fermentation B had lower concentrations of sugars and higher microbial counts than the KLB obtained in fermentation A. In addition, the KLB from fermentation B were the most aromatic and had the highest contents in alcohols, esters, aldehydes and organic acids compared to the non-fermented juice and KLB from fermentation A. These results indicate the possibility of obtaining red table grapes KLB with their own distinctive aromatic characteristics and a high content in probiotic viable cells, contributing to the valorization of this fruit.
Brown marmorated stink bugs (BMSB) release stress compounds, tridecane and (E)-2-decenal, that effect final wine quality. This study focuses on determining the effect of wine processing on (E)-2-decenal and tridecane release in both red and white wines. Wines were produced by adding live BMSB to grape clusters at densities of 0, 0.3, 1 and 3 bugs per cluster. Compound concentrations were measured using HS-SPME-MDGC-MS. For red wines, the highest levels of stress compounds were found using 3 BMSB/cluster (tridecane, 614 µg/L and (E)-2-decenal, 2.0 µg/L). Pressing was found to be the critical process point for stress compound release and additional pressing processes, press type and press fractions, were investigated. BMSB taint for white wines was not found to be problematic to wine quality. An action control of 3 BMSB/cluster is recommended as this related to the known consume rejection threshold for (E)-2-decenal.
The sensory impact of odor-active compounds on icewine aroma could be influenced by perceptual interactions with other odor-active compounds. The aim of this study was to establish an approach to evaluate the contribution of odor-active compounds found in icewine considering mixture-induced perceptual interactions. By comparing the impact of key odorants detected in icewine following a gas chromatography–olfactometry approach with an Olfactoscan-based methodology using a background odor of icewine, 69 odor zones were detected, and their related compounds were further identified. The results revealed that icewine background odor could exert odor masking or enhancement on key odorants when they are considered in the complex wine aroma buffer. Several compounds can induce qualitative changes in the overall wine aroma. This study underlined the efficiency of Olfactoscan-like approaches to screen for the real impact of key odorants and to pinpoint specific compounds that could be highly influential once embedded in the aroma buffer.
Wine quality, regardless of how defined, is impacted by grape quality. Grape quality depends on various metabolites, timing, and completeness of ripening, and the ripening synchrony of skins, seeds, stems, and pulp suited to the type and style of wine desired. Early and late season light, temperature, and water conditions are particularly important in determining the composition of wine grapes; however, there is no single definition for the correct degree of ripeness or quality. Both depend upon the winemaker’s intentions, wine style, secondary grape metabolites aroma/flavor and phenols, structural integrity, and longevity. This chapter considers grape maturity evaluation issues of importance in stylistic winemaking.
The aroma of La Mancha Malbec red wines over four consecutive vintages was characterized by chemical and sensory analysis. Solid phase extraction (SPE) and gas chromatography–mass spectrometry (GC–MS) were used to isolate and analyze free volatile compounds. Quantitative Descriptive Sensory Analysis (QDA) was carried out to characterize the sensory aroma profile. A total of 79 free volatile compounds were identified and quantified in the wines over these four vintages. Volatile aroma compounds were classified into seven aromatic series and their odour activity values were calculated in order to determine the aroma impact compounds in these wines. The aroma sensory profile of these wines was characterized by red fruit, fresh, prune, liquorice, clove, caramel, leather, tobacco and coffee aromas. This study provides a complete aroma characterization of La Mancha Malbec red wines and it is proposed that these wines can be considered as an alternative to wines from traditional grape varieties of this region.
Alcoholic beverages are produced by fermentation of sugars to ethanol. Starting materials range from simple sugars to complex carbohydrates that are reduced to simple sugars by hydrolytic cleavage of starches and dextrins. Beer and wind represent direct products from fermentation whereas vodka, rum, whiskey and other distilled spirits and a distillation step.
The higher alcohols 2-phenylethanol, tryptophol, and tyrosol are a group of yeast-derived compounds that have been shown to affect the aroma and flavour of fermented beverages. Five variants of the industrial wine strain AWRI796, previously isolated due to their elevated production of the ‘rose-like aroma’ compound 2-phenylethanol, were characterised during pilot-scale fermentation of a Chardonnay juice. We show that these variants not only increase the concentration of 2-phenylethanol but also modulate the formation of the higher alcohols tryptophol, tyrosol, and methionol, as well as other volatile sulfur compounds derived from methionine, highlighting the connections between yeast nitrogen and sulfur metabolism during fermentation. We also investigate the development of these compounds during wine storage, focusing on the sulfonation of tryptophol. Finally, the sensory properties of wines produced using these strains were quantified at two time points, unravelling differences produced by biologically modulating higher alcohols and the dynamic changes in wine flavour over aging.
The effects of two cluster thinning regimes (low and moderate) with Vitis vinifera cv. Pinot noir, in vineyards located in Central Otago, New Zealand, on wine composition, were studied across three consecutive seasons. There were strong correlations between the extent of cluster thinning and pH and bunch weights, the concentrations of the C13-norisoprenoids, monoterpenes, fatty acids, cinnamic esters, β-phenylethyl alcohol and all polyphenols. The sensory terms Herbaceous and Acidic consistently received the highest ranking in the control wines without cluster thinning. The thinning treatments produced wines with higher marks in the descriptors Fruity, Spice, Sweet and Body. Cluster thinning also had a measurable effect on timing of harvest, in addition to effects on chemical composition and wine sensory, which demonstrate benefits to wine quality that can be expected with cluster thinning of Pinot noir.
Aromatized wines and regular table wines are often filled on the same bottling line. Sealing polymers in the filling line absorb volatiles from aromatized wines and may migrate due to insufficient cleaning into the subsequently bottled regular wine. Unintentional carryover of volatiles may lead to accusation of illegal aromatization of wine. Absorption, cleaning efficacy, and migration of volatiles into ethylene propylene diene monomer rubber were investigated in a model system. Direct thermal desorption-gas chromatography-mass spectrometry analysis of seven aroma compounds monitored variation in the polymer (μg/g). Absorption of volatiles was mostly driven by their octanol/water partition coefficients. Cleaning of polymers removed 11 to 62% of the absorbed volatiles. Subsequent immersion of cleaned polymers into model wine revealed migration of 20 to 57% of the remaining volatiles. Sensory tests suggested the impact of transferred volatiles into subsequent model wine. For α-ionone, an odor activity value of 1.03 indicated a potential sensory impact.
The effect of amino acids, and their interactions with volatiles and other non‐volatiles, on in‐mouth sensory properties of red wines is not known. This knowledge gap has been studied in a series of comprehensive sensory experiments. A solvent‐assisted flavour evaporation extract of Shiraz wine volatiles, a de‐aromatised polyphenolic extract and amino acids were added to model wine and wine systems. Using full factorial designs, samples were evaluated by sensory quantitative descriptive analysis. Volatiles enhanced Viscous mouthfeel (F = 20.0, P < 0.001), Sweetness (F = 26.5, P < 0.001) and Body (F = 81.4, P < 0.001), while the phenolic extract directed Astringency (F = 170.5, P < 0.001) as well as Bitterness (F = 7.3, P < 0.001) and suppressed Sweetness (F = 16.5, P < 0.001). An amino acid by volatile interaction (F = 4.2, P < 0.05) was found, and further experiments showed that L‐proline enhanced Viscosity (F = 5.0, P < 0.05), Sweetness (F = 14.4, P < 0.001), Red fruit flavour (F = 7.8, P < 0.001) and suppressed Astringency (F = 6.1, P < 0.05) and Bitterness (F = 7.0, P < 0.01), while L‐glutamic acid imparted an Umami taste (F = 5.0, P < 0.05) at wine‐like concentration. For the first time, these causal experiments showed that amino acids can influence the taste, mouthfeel and flavour of red wine. This work provides insight into a new class of wine compounds of sensory significance that can be targeted by producers to directly influence wine flavour.
This study evaluates the effect of microwave treatment in grape maceration at laboratory scale on the content of free and glycosidically bound varietal compounds of must and wines and on the overall aroma of wines produced with and without SO2. The volatile compounds were extracted by solid phase extraction and analyzed by gas chromatography–mass spectrometry, carrying out a sensory evaluation of wines by quantitative descriptive analysis. Microwave treatment significantly increased the free and bound fraction of most varietal compounds in the must. Wines from microwave maceration showed faster fermentation kinetics and shorter lag phase, resulting in an increase in some volatile compounds of sensory relevance. The absence of SO2 caused a decrease in concentration of some volatile compounds, mainly fatty acids and esters. The sensory assessment of wines from microwave treatment was higher than the control wine, especially in wines without SO2, which had higher scores in the “red berry” and “floral” odor attributes and a more intense aroma. This indicates that the pre-fermentative treatment of grapes with microwaves could be used to increase the wine aroma and to reduce the occurrence of SO2.
Four monovarietal red wines from three wine regions in Romania were analysed (Cabernet Sauvignon, Fetească neagră and Pinot noir from two areas in Satu Mare and Fetească neagră and Merlot from Constanța) in a liquid-liquid extraction with dichloromethane by gas chromatography-mass spectrometry (GC-MS). The odor activity value (OAV) was calculated in the 29 aroma compounds identified: 10 alcohols, 11 esters, 5 fatty acids, 1 lactone and 2 other compounds. Wines were differentiated by specific compounds and 22 of the volatile compounds had an OAV>1 (7 alcohols, 9 esters, 5 fatty acids and 1 lactone), significantly contributing to wine aromas. All chemicals changed in the volatile composition: most alcohols and acids increased during ageing, while all esters increased with ageing time. According to their OAVs, aroma strongly influenced the characteristics of the four monovarietal wines.
This study aimed to identify the key aroma-active volatiles in cranberry wines through three vinification methods (White, Red and Thermo) using GC-MS/O to identify the important aroma compounds. A total of 70 compounds were detected, with 67 in wines and 61 in juices. The esters was the most diversified class, while alcohols and acids were the most abundant, especially 3-methyl-1-butanol, methylbutyric acid, and benzoic acid. The volatile profiles of cranberry wines are distinctive from their source juices. Most alcohols, esters, and acids are fermentation-derived, while terpenes, phenols, aldehydes and ketones are varietal. The Red vinification retained the most varietal volatiles from the must, while the White and Thermo vinifications produced more volatiles during fermentation. Thermovinification reduced the yield of benzoic acid and its derivatives after fermentation. Olfactory analysis identified 47 aroma-active compounds, among which 41 were considered as the major aroma contributors (ethyl benzoate had the highest modified detection frequency).
The overall aroma is an important factor of the sensory quality of fruit wines, which attributed to hundreds of volatile compounds. However, the qualitative determination of trace volatile compounds is considered to be very challenging work. GC-Orbitrap-MS with high resolution and high sensitivity provided more possibilities for the determination of volatile compounds, but without the high-resolution mass spectral library. For accuracy of qualitative determination in fruit wines by GC-Orbitrap-MS, a high-resolution mass spectral library, including 76 volatile compounds, was developed in this study. Not only the HRMS spectrum but also the exact ion fragment, relative abundance, retention indices (RI), CAS number, chemical structure diagram, aroma description and aroma threshold (ortho-nasally) were provided and were shown in a database website (Food Flavor Laboratory, http://foodflavorlab.cn/). HRMS library was used to successfully identify the volatile compounds mentioned above in 16 fruit wines (5 blueberry wines, 6 goji berry wines and 5 hawthorn wines). The library was developed as an important basis for further understanding of trace volatile compounds in fruit wines. Measurement(s)volatile compoundsTechnology Type(s)GC-Orbitrap-MS Measurement(s) volatile compounds Technology Type(s) GC-Orbitrap-MS
p style="text-align: justify;">Nous nous sommes intéressés à certaines nuances aromatiques caractéristiques des vins de Sauvignon. En utilisant le couplage de la chromatographie en phase gazeuse à la détection odométrique en sortie de colonne, nous avons mis en évidence dans des extraits de vins de Sauvignon une zone odorante rappellant le buis et le bourgeon de cassis. Une méthode, basée sur la mesure de la durée de perception de cette odeur caractéristique au cours de l'analyse odométrique, permet d'apprécier son intensité dans les vins. Nous démontrons ainsi le rôle de la souche de levure qui réalise la fermentation alcoolique sur l'intensité de l'arôme variétal des vins de Sauvignon.</p
Twenty rose and ten claret A.O.C. Bordeaux wines made from Cabernet Sauvignon, Cabernet franc and Merlot grapes were separately tasted by the same jury of ten professionals. They were asked to classify the wines according to the intensity of the fruity character. The fruitiest sample was given first rank. The wines’ bdamascenone, b-ionone, phenyl-2-ethanol, isoamyl acetate, phenyl-ethyl acetate (APE), 3-mercaptohexan-1-ol (3MH) and 3-mercaptohexyl acetate (A3MH) contents were also measured. The higher the latter three compounds' values, the higher the wines’ fruity character. Highly significant correlation were found between the sensorial analysis results and these compounds contents. In order to confirm the 3MH, A3MH and APE contribution to the fruity aroma of rose wines, a tasting has been carried out. For this, these three compounds were added to a rose wine up to the concentrations found in the wine judged the fruitiest by the tasters. 100 % of the tasters identified the supplemented glasses, and 90 % prefered the supplemented wine. This second experiment clearly demonstrate that 3MH, A3MH and APE can be considered key components of Bordeaux rose wines’ fruity aroma.
The production of APE by yeast has been known for a long time. The 3MH is present in must under cysteinylated precursor form. The transformation of the precursor into aroma is made by the Saccharomyces cerevisiae yeasts during alcoholic fermentation. Thus the choice of yeast strains has a decisive impact on the fruity aroma of Bordeaux rose and claret wines.
Capillary-column gas chromatography was used to determine 63 aroma compounds in 9 very pale sherry wines, fino type, subjected to biological ageing under industrial conditions for 1, 3 and 5 years. The contents in aroma compounds were related to the wine ageing time by means of a simple linear regression model. The compounds that exhibited a high correlation coefficient (r>0.90) and simultaneously a high odour impact value (OAV > 5) were additionally subjected to principal component analysis. The first component was found to account for 93.12% of the changes in such compounds during the biological ageing process. The greatest contributions to this component were those from sotolon and 1,1-diethoxyethane, both related to the acetaldehyde produced by the metabolism of flor yeasts, and Z-whisky lactone synthesized from its precursors extracted from the casks wood where the wines were aged. The use of these compounds as markers for biological ageing is advantageous because their changes in concentrations is taken into account as well as their odorant impact.
Fifty‐two young monovarietal red wines made with Grenache (17 samples), Tempranillo (11 samples), Cabernet Sauvignon (12 samples) and Merlot (12 samples) grapes have been analysed by HRGC–MS to obtain quantitative data on 47 odorants previously identified as potential aroma contributors by olfactometric techniques. Thirty‐three odorants were present in the wines at concentrations higher than their corresponding odour thresholds. These include ethyl octanoate, β‐damascenone, ethyl hexanoate, isovaleric acid and isoamyl acetate as the most important, which together with isoamyl and β‐phenylethyl alcohols, fatty acids, 2,3‐butanedione and ethyl butyrate are always found at concentrations higher than their odour thresholds. In some cases the ethyl esters of isobutyric and isovaleric acids, β‐ionone, methionol, isobutyric acid, ethyl cinnamate, ethyl dihydrocinnamate, γ‐nonalactone, eugenol, c‐3‐hexanol, geraniol, guaiacol, 3‐isobutyl‐2‐methoxypyrazine, 4‐ethylguaiacol, acetoin and t‐whiskylactone were at a concentration high enough to be odour‐active. There were 30 compounds that were found to differ significantly between varieties. These include 3‐isobutyl‐2‐methoxypyrazine, isoamyl acetate, isovaleric acid, ethyl isobutyrate, ethyl isovalerate, fusel alcohols, c‐3‐hexenol, methionol, eugenol, guaiacol and γ‐nonalactone.
© 2000 Society of Chemical Industry
Two new components of botrytised wine were identified: 4,5-dimethyl-3-hydroxy-2(5H)-furanone (Sotolon) and ethyl 9-hydroxynonanoate. Sotolon, the key substance of cane sugar aroma, was identified as the sugary flavor substance of botrytised wine by means of gas chromatography-mass spectrometry after column chromatographic separation on DEAE-Sephadex and silica gel. Ethyl 9-hydroxynonanoate was identified by chemical ionization and electron impact mass spectrometry. To evaluate the role of 17 volatile and 5 nonvolatile compounds characteristic of botrytised wine, these compounds were added to a normal wine. This produced a sweet, honey-like flavor similar to that of botrytised wine. The importance of Sotolon and the role of each group of flavor substances in producting this flavor was clarified by omission tests. © 1984, Japan Society for Bioscience, Biotechnology, and Agrochemistry. All rights reserved.
Two new components of botrytised wine were identified: 4,5-dimethyl-3-hydroxy-2(5H)-furanone (Sotolon) and ethyl 9-hydroxynonanoate. Sotolon, the key substance of cane sugar aroma, was identified as the sugary flavor substance of botrytised wine by means of gas chromatography-mass spectrometry after column chromatographic separation on DEAE-Sephadex and silica gel. Ethyl 9-hydroxynonanoate was identified by chemical ionization and electron impact mass spectrometry. To evaluate the role of 17 volatile and 5 nonvolatile compounds characteristic of botrytised wine, these compounds were added to a normal wine. This produced a sweet, honey-like flavor similar to that of botrytised wine. The importance of Sotolon and the role of each group of flavor substances in producting this flavor was clarified by omission tests.
For more than two decades, this work has remained the leading advanced textbook and easy-to-use reference on food chemistry and technology. Its fourth edition has been extensively re-written and enlarged, now also covering topics such as BSE detection or acrylamide. Food allergies, alcoholic drinks, or phystosterols are now treated more extensively. Proven features of the prior editions are maintained: Contains more than 600 tables, almost 500 figures, and about 1100 structural formulae of food components - Logically organized according to food constituents and commodities - Comprehensive subject index. These features provide students and researchers in food science, food technology, agricultural chemistry and nutrition with in-depth insight into food chemistry and technology. They also make the book a valuable on-the-job reference for chemists, food chemists, food technologists, engineers, biochemists, nutritionists, and analytical chemists in food and agricultural research, food industry, nutrition, food control, and service laboratories. From reviews of the first edition "Few books on food chemistry treat the subject as exhaustively-researchers will find it to be a useful source of information. It is easy to read and the material is systematically presented." JACS.
Selective extraction of volatile mercaptans present in wines at trace levels, combined with capillary gas chromatographic (GC) analysis using flame photometric detector (FPD) revealed the presence of a previously unreported compound in Sauvignon wine. 3-mercaptohexylacetate was identified by comparison of chromatographic and mass spectrum data with those of the reference compound. This mercapto ester, recently found in passion-fruit, exhibits aroma reminiscent of box tree with grapefruit and passion fruit notes. Its perception threshold in water and model solution is around 2-4 ng/l. 3-mercaptohexylacetate may contribute to the typical varietal aroma of Sauvignon wines.
Five volatile thiols previously identified in Sauvignon blanc wines, 4-mercapto-4-methylpentan-2-one (4MMP), 4-mercapto-4-methylpentan-2-ol (4MMPOH), 3-mercapto-3-methylbutan-1-ol (3MMB), 3-mercaptohexan-1-ol (3MH) and 3-mercaptohexyl acetate (A3MH) were found to be present in wines made from several other white Vitis vinifera grape varieties. An assay of these volatile thiols showed that concentrations of 4MMP, 3MH, and A3MH were considerably higher than the perception thresholds in certain wines made from Gewurztraminer, Riesling, Colombard, Petit Manseng, and botrytized Semillon. The impact of volatile thiols on the aromas of wines made from these grape varieties was investigated for the first time.
p style="text-align: justify;">This study is dedicated to quantification, by gas chromatography combined with mass spectrometry, of some volatile compounds founded during ageing of sweet natural wines. Besides determination of the thresholds olfactory perception enable us knowing better the more active compound in sweet natural wines aroma.
The results enable to know better volatile compounds which are able to produce ageing aromas characteristic of sweet natural wines. These products are always rich in sugar and grown up in a more or less oxidising environment. Logically, many of the compounds identified in this work (derived furanic compounds and many others) are Iinked with chemical like Maillard reactions between sugars and amino-acids. Others compounds as a sotolon need oxidising phenomena to increase in the environment.
Comparatively, oldest Port wines have been analysed. The compounds measured in these Port wines also exist in French sweet natural wines of type Banyuls and Rivesaltes, keeped under oxidising environment. But the dillerences of concentrations in some compounds discriminate them from the Port wines.</p
The characteristic aroma of Petite Arvine, a local white wine specialty prepared from the autochthone grape variety Petite Arvine in Valais, Switzerland, is described as intense in grapefruit and rhubarb flavors. In sensory evaluation by a triangle-test, the impact of thiol compounds on the wine aroma was demonstrated. In gas chromatography-olfactometry and gas chromatography-mass spectrometry analyses, 3-mercaptohexanol was identified as one of the key aroma compounds for the wine aroma. The concentration of 3-mercaptohexanol in 11 Petite Arvine wines was in the range between 210 and 6100 ng/L; all values being above the odor threshold value in aqueous ethanol solutions for this compound. Copyright © 2005 by the American Society for Enology and Viticulture. All rights reserved.
The existence of synergic, additive or antagonistic effects between mixtures of compounds showing simillr chemical structures and/or odours has been studied. The odour threshold of a mixture of aliphatic γ-lactones is four times lower than that expected from the individual thresholds, which evidences a strong synergic effect. In the case of compounds with burnt sugar notes, the odour threshold of the mixture is exactly that expected from the individual thresholds (additive effect). In the case of vanillin-related compounds an antagonistic effect was observed.
Seventy-two young commercial Spanish wines from the 1990 harvest were analysed during the first semester of 1991. Analytical data on 52 volatile compounds were obtained. Diverse multivariate analysis methods were utilized to study these data in order to obtain a factorization so that an interpretation of the role played by grape variety and origin could be made. Cluster analysis showed similar aroma profiles according to site or grape variety, and a strong influence of the presence of skins during fermentation. Discriminant analysis has shown that wine volatile composition contains enough information to establish a consistent control of authenticity, allowing the assessment of the origin or grape variety of very different wine samples through a common function. Origin and grape variety are two interactive factors that strongly influence wine volatile composition. Origin affects mainly the amount and proportion of compounds derived from unsaturated lipid in the grape and volatile derived from yeast aminoacid, while grape variety affects mainly this latter group of compounds.
Diacetyl, an important wine flavorant synthesized during alcoholic and malolactic fermentation, has been reported to have a sensory threshold of 2–3 mg/l. A comparative study of threshold for diacetyl in wines was undertaken to determine the effect of wine type on that value. Sensory threshold was determined according to the forced-choice ascending concentration series of limits method described by ASTM (E 679-79), using trained panelists. Panel detection thresholds and standard deviation from the geometric mean were found to be 0.2 mg/l and 0.32 in Chardonnay, 0.9 mg/l and 0.21 in Pinot noir, and 2.8 mg/l and 0.38 in Cabernet Sauvignon. These results demonstrate the important effect of wine type on diacetyl threshold, invalidating the use of a single threshold value for all wines.
The flavour of virgin olive oil was investigated by means of an aroma extract dilution analysis. A comparative study of four oil samples differing in the flavour, indicated that the following odorants were mainly responsible for the odour notes given in brackets: (Z)-3-hexenol, hexanal, (E)-2-hexenal and (Z)-3-hexenal (green), ethyl 2-methylbutyrate, (Z)-3-hexenyl acetate and ethyl cyclohexanoate (fruity), (E,E)-2,4-decadienal, (E)- and (Z)-2-nonenal (fatty) and 4-methoxy-2-methyl-2-butanethiol (black currant-like).
Vergleichende Untersuchung über intensive Geruchsstoffe von verschiedenen extra vierge Olivenölen
Das Aroma von extra vierge Olivenölen wurde mittels Aromaextraktverdünnungsanalyse untersucht. Ein Vergleich von vier Olivenölen mit unterschiedlichem Aroma zeigte, daß die folgenden Geruchsstoffe hauptsächlich für die in Klammern angegebenen Geruchsnoten verantwortlich waren: (Z)-3-Hexenol, Hexanal, (E)-2-Hexenal und (Z)-3-Hexenal (grün), Ethyl-2-methylbutyrat, (Z)-3-Hexenylacetat und Ethylcyclohexanoat (fruchtig), (E,E)-2,4-Decadienal, (E)-2-Nonenal und (Z)-2-Nonenal (fettig) sowie 4-Methoxy-2-methyl-2-butanthiol (nach schwarzen Johannisbeeren).
The use of a new technique combining low-temperature vacuum distillation with a specific chemical capture with an organomercuric compound enabled the extraction of volatile odorous thiols present at very low concentrations in the Bordeaux red wine varieties Merlot and Cabernet Sauvignon. The analysis of wine extracts by gas chromatography coupled with detection by olfactometry, flame photometry, and mass spectrometry led to the identification of three aromatic thiols: 3-mercapto-2-methylpropanol, identified for the first time in wine; 3-mercaptohexanol; and 3-mercaptohexyl acetate, already described in Sauvignon Blanc wines. Keywords: Vacuum distillation; p-hydroxymercuribenzoate; aroma; 3-mercapto-2-methylpropanol; 3-mercaptohexanol; 3-mercaptohexyl acetate; Bordeaux red wines; Cabernet Sauvignon; Merlot
Forty-four odor-active compounds were quantified in Scheurebe and Gewürztraminer wines, respectively. Calculation of odor activity values (OAVs) of odorants showed that differences in odor profiles of both varieties were mainly caused by cis-rose oxide in Gewürztraminer and by 4-mercapto-4-methylpentan-2-one in Scheurebe. On the basis of their high OAVs, ethyl octanoate, ethyl hexanoate, 3-methylbutyl acetate, ethyl isobutyrate, (E)-β-damascenone, and 3a,4,5,7a-tetrahydro-3,6-dimethylbenzofuran-2(3H)-one (wine lactone) were further potent odorants in both varieties. The compounds were dissolved in a water/ethanol mixture in various combinations and in concentration levels equal to those in wine. The results indicated that the aromas of Gewürztraminer and Scheurebe models were in good agreement with the original wines. Keywords: Gas chromatography; stable isotope dilution assay; quantitation; white wine; Gewürztraminer; Scheurebe
Since objective measures of appellations are needed for wine, California Vitis vinifera Var. Chardonnay wines (n = 48) were surveyed for several aroma compounds including esters, norisoprenoids, and terpenes. For the first time concentrations of volatile fragrances were directly correlated with descriptive analysis scores that statistical analysis of the sensory data showed were associated with regional uniqueness and distinctness. Sensory scores for 10 terms used by industry quality experts to describe wines from four regions were compared to the concentrations of over 30 wine chemical compounds. Frequency of use of individual grape-based aroma terms were significantly correlated (p < 0.05) with linalool, 1,1,6-trimethyldihydronaphthalene, 3-methylbutyl acetate, ethyl 2-hydroxypropanoate, and 2-phenylethanol. Linalool concentrations were also correlated with α-terpineol. Also, 4-terpineol, geraniol, nerol, and linalool oxide (furan) were found in Chardonnay wines from all of the regions of California. Keywords: Aroma; Chardonnay; descriptive analysis; flavorants; norisoprenoids; sensory analysis; terpenoids; terroir; Vitis vinifera; wine
The terpenic derivatives that occur in the aroma of Muscat grapes have been studied by gas and thin-layer chromatography and by infrared and mass spectrophotometry. Eight compounds have been identified: linaiol, geraniol, nerol, α-terpineol, two furanic, and two piranic oxides of linalol. Furthermore, two other substances that are not identified definitively have been placed in a prominent position. The terpenes of the Muscat juice have been titrated individually by gas chromatog-raphy, after concentration by salting-out of the aqueous solution into an extractive solvent; the total content varies between 1 and 3 mg/l The influence of each substance on the whole aroma has been precisely checked by the determination of thresholds, which vary between 100 and more than 6000 μg/. Some transformations of terpenes may explain the losses of aroma that are sometimes observed during the processing and the storage of grape juices and wines.
The olfactory impact of sotolon [4,5-dimethyl-3-hydroxy-2(5H)-furanone] in wines was first demonstrated in botrytized wines. In sherry wines it was recently found to occur at concentrations varying from 0 to 500 ppb. The olfactory detection threshold of a sample of purified racemic sotolon was determined to be lower (15 ppb) in white wine than its concentration in most sherries. Its flavor impact in sherries was calculated to be between 1 and 25 OUV. Using MCA of the data obtained from 22 wines (white wines, rancios, Spanish and French sherries) during two tasting sessions by wine professionals, significant positive correlations were found between the concentration of sotolon and the typicality as well as between the concentration and the persistence in the mouth of a nutty flavor.
The quantitative olfactory interactions in three binary mixtures of wine aroma compounds were studied. For the first two mixtures, whisky lactone (woody note) was mixed separately with two esters (fruity note), ethyl butyrate and isoamyl acetate. For the third mixture, guaiacol (woody note) was mixed with ethyl butyrate (fruity note). Perceived odour intensity of 24 stimuli (four supra-threshold concentration levels of two compounds and the respective 16 mixtures) were evaluated in five replications, by a trained panel of 13 subjects. The results showed that for the three binary mixtures studied, quantitative perceptual interactions were non-level independent, non-symmetrical, and reached the compromise level of hypo-addition. The experimental data highlighted that generally mixtures with high whisky lactone levels led to the compromise level of mixture intensity perception, whereas mixtures with high fruity note intensity proportions did not. A tendency to hyper-addition was observed in iso-intense mixtures only at the lowest intensity level. Copyright © 2004 John Wiley & Sons, Ltd.
Wines which have undergone malo-lactic fermentation contain significantly more diacetyl and acetoin than wines which have not. The amounts of diacetyl and acetoin formed depend on the type of bacterium present and on the composition of the wine. Leuconostoc mesenteroides is the chief organism forming these products in Australian wines while pyruvic acid and citric acid are the chief substrates from which they are formed. The presence of a few g. per litre of glucose interferes with the formation of these products in wine.The heterofermentative rods, Lact. hilgardii and Lact. brevis, which are responsible for malo-lactic fermentation in some Australian wines, produce diacetyl and acetoin only under conditions unlikely to occur in wines. Homofermentative lactobacilli have not yet been isolated from Australian wines.