Aroma Descriptors Research Articles

Electron Delocalization in Planar Metallacycles: Hückel or Möbius Aromatic?

In this work the relationship between the formal number of π‐electrons, d‐orbital conjugation topology, π‐electron delocalization and aromaticity in d‐block metallacycles is investigated in the context of recent findings concerning the correlation of π‐HOMO topology and the magnetic aromaticity indices in these species. It is demonstrated that for π‐electron rich d‐metallacycles the direct link between aromaticity, the number of π‐electrons and the frontier π‐orbital topology does not strictly hold and for such systems it is very difficult to unambiguously associate their aromaticity with the “4n+2” (Hückel) and “4n” (Möbius) rules. It is also shown that the recently proposed electron density of delocalized bonds (EDDB) method can successfully be used not only to quantify and visualize aromaticity in such difficult cases, but also – in contrast to magnetic aromaticity descriptors – to provide a great deal of information on the real role of d‐orbitals in metallacycles without the ambiguity of bookkeeping of electrons in the π‐subsystem of the molecular ring. Interestingly, some of the metallacycles studied cannot be classified exclusively as Hückel or Möbius because they have a hybrid Hückel‐Möbius or even quasi‐aromatic nature.

The aroma of La Mancha Chelva wines: Chemical and sensory characterization

The aim of this study is the chemical and sensory description of the aroma of wines white Chelva through five successive vintages. Solid Phase Extraction (SPE) was used for the isolation of volatile compounds and Gas Chromatography Mass Spectrometry (GC–MS) was employed by their analysis. Aroma Sensory Profile of wines was defined using the Quantitative Descriptive Sensory Analysis (QDA). A total of 77 volatile compounds were identified in Chelva wines. Chelva wines present a great quantity of aromatic compounds of very different chemical nature and with different aromatic descriptors, which will increase its aromatic complexity of these wines. Aroma sensory profile of Chelva wines was defined by higher intensity of fresh and peach aromas with notes citric, green apple, tropical fruit and sweet. This study showed that the Chelva grapes variety cultivated in La Mancha region present a great aroma potential and a complex sensory profile and can be considered a viable alternative to traditional grape varieties cultivated in this region for increasing the offer to the consumer.

Effects of Harvest Time on the Aroma of White Wines Made from Cold-Hardy Brianna and Frontenac Gris Grapes Using Headspace Solid-Phase Microextraction and Gas Chromatography-Mass Spectrometry-Olfactometry.

The Midwest wine industry has shown a marked increase in growers, hectares planted, wineries, and wine production. This growth coincides with the release of cold-hardy cultivars such as Brianna and Frontenac gris, in 2001 and 2003, respectively. These white grape varieties account for one-third of the total area grown in the state of Iowa. It is generally accepted that the wine aroma profile plays a crucial role in developing a local, sustainable brand. However, the identity of Brianna/Frontenac Gris-based wine aromas and their link to the grape berry chemistry at harvest is unknown. This study aims to preliminarily characterize key odor-active compounds that can influence the aroma profile in wines made from Brianna and Frontenac gris grapes harvested at different stages of ripening. Brianna and Frontenac gris grapes were harvested approximately 7 days apart, starting at 15.4 °Brix (3.09 pH) and 19.5 °Brix (3.00 pH), respectively. Small batch fermentations were made for each time point with all juices adjusted to the same °Brix prior to fermentation. Odor-active compounds were extracted from wine headspace using solid-phase microextraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS) and simultaneous olfactometry (O). Over 30 odor-active compounds were detected. Aromas in Brianna wines developed from “cotton candy” and “floral”, to “banana” and “butterscotch”, then finally to “honey”, “caramel” and an unknown neutral aroma. Frontenac gris wines changed from an unknown neutral aroma to “fruity” and “rose”. Results from the lay audiences’ flavor and aroma descriptors also indicate a shift with harvest date and associated °Brix. To date, this is the first report of wine aromas from Brianna and Frontenac gris by GC-MS-O. Findings from this research support the hypothesis that aroma profiles of Brianna and Frontenac gris wines can be influenced by harvesting the grapes at different stages of ripening.

Quantifying the conceptual problems associated with the isotropic NICS through analyses of its underlying density.

The isotropic Nucleus Independent Chemical Shift (NICSiso) is widely considered to be a suitable descriptor for aromaticity based on the correlations it exhibits with other aromaticity descriptors. To gain more insight into the origin of these correlations, we establish causal relations between the NICSiso and the underlying current density patterns by resolving the NICSiso into its underlying density. Our results indicate that the origin of the behavior of the NICSiso can be radically different from what is generally assumed. Not only does this bring into question the robustness of applying the NICSiso beyond the realms of where good correlations with other measures of aromaticity have been established, it also points to an inherent weakness in all interpretations of NICSiso values that are not based on additional data.

Sensory Profile of Chihuahua Cheese Manufactured from Raw Milk

Chihuahua cheese is a local artisanal cheese traditionally produced from raw milk. When this cheese is produced with pasteurized milk, cheesemakers complain that there are differences in taste and aroma as compared with traditional manufacturing. This work aimed to obtain a descriptive sensory analysis of Chihuahua cheese manufactured with raw milk under traditional conditions. Samples were collected in five cheese dairies at two different seasons (summer and autumn), and a Quantitative Descriptive Sensorial Analysis was done by a panel of trained judges. For aroma descriptors, cooked descriptor showed differences between dairies, and whey was different among dairies and sampling seasons (P<0.01); diacetyl, fruity (P<0.01), as well as free fatty acids, nutty and sulphur (P<0.05) descriptors varied between seasons. For flavour descriptors, bitter perception was different between dairies and seasons (P<0.01). Salty and creamy cheese was also different among dairies (P<0.01). A Principal Component Analysis for differences among dairies and sampling season demonstrated that the first three components accounted for 90% of the variance; variables were more affected by the sampling seasons than by the geographical location or if the dairy was operated by Mennonites. Chihuahua cheese sensorial profile can be described as a semi-matured cheese with a bitter flavour, slightly salted, and with a cream flavour, with aroma notes associated with whey and sour milk. Principal Component Analysis demonstrated season influence on flavour and aroma characteristics.

Changes Occurring in the Volatile Constituents of Flaxseed Oils (FSOs) Prepared with Diverse Roasting Conditions

The roasting process is the most significant factor in forming the final flavor character of FSO. A wide variety of volatile constituents in FSO prepared from flaxseeds that were roasted at different temperatures are evaluated by head‐space solid phase micro‐extraction (HS‐SPME) coupled with GC‐MS. There are 69 volatile constituents that are tentatively identified, and the sensory variance analysis indicates that all of the FSO samples gives comparable intensity values for the “oily” and “herbaceous”aroma descriptors, and the odor profiles of the FSO samples differed significantly with regards to the “roasted” and “almond” aromas (p &lt; 0.05). The principal component analysis (PCA) of the volatiles showed the first principal component (PC‐1) and the second principal component (PC‐2) express 84 and 9% of the volatile component variability in the FSO, respectively, which can clearly differentiate FSOs prepared from different roasting conditions. Additionally, the loadings plot further shows that the RFSO correlated more with three groups of volatile constituents according to the degree of roasting (with the total numbers and numbers of specific compounds between brackets): aldehydes (19:2, (E, E)‐2,4‐pentadienal, (E, E)‐2,4‐heptadienal), ketones (9:3,2‐hexanone, (E)‐3‐octen‐2‐one, 5‐methyl‐2(5H)‐furan‐one), and heterocyclic compounds (11:4, 2,3‐dimethylpyrazine, trimethylpyrazine, 2‐ethyl‐furan, 2‐ethyl‐6‐methylpyrazine).Practical Applications: Monitoring of the roasting process is an unavoidable task to obtain the desired volatiles and taste to ensure RFSO quality constant at an industrial level. In general, the most adopted indicator to control the degree of roasting in industry is visual inspection, which may not be accurate for the quality evaluation because RFSO presented the same average color value although they are derived from different roasted degree. Different resources will imply in variable volatile constituents for the same type of flaxseeds. It is therefore known that FSOs produced from different roasting processing may be differentiated by their volatile constituents. The results show that the major volatile constituents can be used as chemical markers to distinguish different processed RFSO by the PCA method.The roasting process contributes the most in forming the final flavor character of flaxseed oils (FSOs). By increasing the roasting temperature, the color of FSOs changed gradually from light yellow (0–40 min) to brown (40 min) and finally to deep‐brown (50 min). A wide variety of volatile compounds in FSOs are evaluated and compared with those of unroasted FSO by HS‐SPME‐GC‐MS and sensory variance. The sensory variance analysis indicates that the odor profiles of FSO samples differed significantly with regards to the “roasted” and “almond” aromas (p &lt; 0.05). PCA analysis can clearly differentiate FSOs prepared from different roasting conditions.

Effect of the winemaking process on the volatile composition and aromatic profile of Tempranillo Blanco wines.

The effects of the carbonic maceration and conventional winemaking on the volatile composition and aromatic sensory characteristics of Tempranillo Blanco wines were studied for the first time, during three consecutive vintages. Relationships between instrumental (volatiles) and sensory variables were analyzed applying partial least squares regression (PLS). Carbonic macerated wines had higher contents of alcohols and carbonyl compounds, yet lower concentrations of C6 alcohols and volatile acids than wines conventionally produced. The Odor Activity Values (OAV) exhibited an increase in wines when carbonic maceration was applied. According to the geometric mean (% GM) obtained from aroma descriptors the effect of the winemaking process was significant for seed fruit, ripe fruit and floral notes. When subjected to PLS the data from the instrumental analysis yielded a satisfactory model for the prediction of aroma descriptors in this set of wines.

Aromaticity as a Guiding Concept for Spectroscopic Features and Nonlinear Optical Properties of Porphyrinoids.

With their versatile molecular topology and aromaticity, porphyrinoid systems combine remarkable chemistry with interesting photophysical properties and nonlinear optical properties. Hence, the field of application of porphyrinoids is very broad ranging from near-infrared dyes to opto-electronic materials. From previous experimental studies, aromaticity emerges as an important concept in determining the photophysical properties and two-photon absorption cross sections of porphyrinoids. Despite a considerable number of studies on porphyrinoids, few investigate the relationship between aromaticity, UV/vis absorption spectra and nonlinear properties. To assess such structure-property relationships, we performed a computational study focusing on a series of Hückel porphyrinoids to: (i) assess their (anti)aromatic character; (ii) determine the fingerprints of aromaticity on the UV/vis spectra; (iii) evaluate the role of aromaticity on the NLO properties. Using an extensive set of aromaticity descriptors based on energetic, magnetic, structural, reactivity and electronic criteria, the aromaticity of [4n+2] π-electron porphyrinoids was evidenced as was the antiaromaticity for [4n] π-electron systems. In agreement with previous studies, the absorption spectra of aromatic systems display more intense B and Q bands in comparison to their antiaromatic homologues. The nature of these absorption bands was analyzed in detail in terms of polarization, intensity, splitting and composition. Finally, quantities such as the average polarizability and its anisotropy were found to be larger in aromatic systems, whereas first and second hyperpolarizability are influenced by the interplay between aromaticity, planarity and molecular symmetry. To conclude, aromaticity dictates the photophysical properties in porphyrinoids, whereas it is not the only factor determining the magnitude of NLO properties.

Comparison of two analytical methods validated for the determination of volatile compounds in virgin olive oil: GC-FID vs GC-MS

The utility of volatile compounds to explain virgin olive oil aroma descriptors is fully accepted and demanded by the olive oil sector. However, the methodology, and particularly the kind of detector to be used, is a matter of discussion because the high number of volatiles and their different nature. The SPME-GC-MS method has recently been validated for the most relevant volatiles but SPME-GC-FID method still needs to be validated to evaluate its performance in this application. A comparison between these two GC methods in determining 26 volatiles has been carried out in terms of analytical quality parameters (repeatability, intermediate precision, calibration curves, limits of detection and quantification, linear working ranges, selectivity and sensitivity). Good selectivity, linearity and higher upper values of the working range are the main advantages of SPME-GC-FID versus low bottom values of working ranges, better sensitivity and lower limits of detection and quantification of SPME-GC-MS. The limit of blank associated to each individual volatile was also determined and it allowed perfecting the empirical limit of detection. This procedure was carried out for SPME-GC-FID, which resulted in 21 volatiles with empirical limits of detections lower than their odor thresholds, and hence they can be used as markers of virgin olive oil sensory descriptors. Finally, with all the analytical quality parameters checked, a practical example of the ability of the volatiles quantified by SPME-GC-FID to discriminate the different categories (extra-virgin, virgin and lampante) and their main aroma descriptors is also provided.

Red wine produced from the Isabella and Ives cultivar (Vitis Labrusca): profile of volatiles and aroma descriptors

Abstract Considering the potential consumption and economic the importance that Isabella and Ives wines represent in the Brazilian consumer market as well as the scarcity of scientific data examining their quality, the objective of this study was to investigate the sensory quality and the volatiles profile of these wines. The volatile compounds were extracted by headspace solid-phase microextraction (HS-SPME) and a total of 54 compounds were detected in red wine samples including esters (23), terpenes (12), alcohols (10), aldehydes and ketones (5) and amines (1) as well as 3 compounds belonging to other classes. Isabella and Ives red wines were sensorially characterized by 14 descriptors, through quantitative descriptive analysis (QDA). The PCAs fruity descriptors were the primary contributors to the aroma profile of the analyzed wines due to the presence of ethyl acetate and esters, especially in the wine coded as QM, which exhibited the highest variety of compounds. The differences observed in the principal components analysis, might have been influenced by the grape composition of each wine. Although the wines were from the same region, each came from a different winery and was subject to unique production processes.

Torulaspora delbrueckii for secondary fermentation in sparkling wine production

In the search for the desired oenological features and flavour complexity of wines, there is growing interest in the potential use of non-Saccharomyces yeast that are naturally present in the winemaking environment. Torulaspora delbrueckii is one such yeast that has seen profitable use in mixed fermentations with Saccharomyces cerevisiae and with different grape varieties. T. delbrueckii can have positive and distinctive impacts on the overall aroma of wines, and has also been used at an industrial level. Here, T. delbrueckii was successfully used in pure and mixed secondary fermentations for sparkling wine. The two selected T. delbrueckii strains used completed the secondary fermentation ‘prise de mousse’ in these pure and mixed fermentations. The sparkling wines obtained with T. delbrueckii showed different aromatic compositions and sensory profiles to those of S. cerevisiae. T. delbrueckii strain DiSVA 130 showed high esters production and significantly high scores for some of the aromatic descriptors that positively influence the sensory profile of sparkling wine. Thus, the use of T. delbrueckii in pure and mixed fermentations is a suitable strategy to further develop the flavour complexity during secondary fermentation of sparkling wines.

The molecular structure of 5-X-isatines where (X = F, Cl, and Br) determined by gas-phase electron diffraction with theoretical calculations

The molecular structures of 5-X-isatines where X = F (1), Cl (2), and Br (3) were studied by gas-phase electron diffraction (GED) and theoretical calculations at M062X/aug-cc-pVTZ and MP2/aug-cc-pVTZ levels. The best fit of the experimental scattering intensities was obtained for a molecular model of Cs symmetry. The small differences between similar geometric parameters were constrained at the values calculated at the M062X level. The bond distances in the benzene ring are in agreement with their standard values. The (O)CC(O) carbon-carbon bonds of the pyrrole moiety in title compounds (1.581(11), 1.578(8), 1.574(12) Å, respectively) are remarkably lengthened in comparison with standard C(sp2)–C(sp2) value, 1.425(11) Å for N-methylpyrrole. According to NBO analysis this lengthening cannot be attributed to the electrostatic repulsion of oxygen lone pairs alone and is, mainly, due to the hyperconjugation, that is delocalization of oxygen lone pairs of π-type into the corresponding carbon-carbon antibonding orbital, nπ(O)→σ*(CC). Deletion of σ*(CC) orbital followed by subsequent geometry optimization led to shortening of the corresponding CC bond by 0.05–0.06 Å. Electronegative halogen atoms led to increase of CCXC endocyclic bond angles at ipso carbon atom as compared with the value of 120° in regular hexagon. According to different aromaticity descriptors, aromaticity of benzene moiety of title compounds is smaller in comparison with benzene molecule. External magnetic field induces diatropic ring current in benzene moiety. Local reactivity descriptors that indicate sites in a molecule that are susceptible to nucleophilic, electrophilic and radical attack are calculated.

Impact of cherry, acacia and oak chips on red wine phenolic parameters and sensory profile

&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Aim:&lt;/strong&gt; The evolution of global phenolic parameters and the sensory profile of a Portuguese red wine aged for 90 days in contact with wood chips from different species were evaluated.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Methods and results:&lt;/strong&gt; For this purpose, wood chips from cherry (&lt;em&gt;Prunus avium&lt;/em&gt;), acacia (&lt;em&gt;Robinia pseudoacacia&lt;/em&gt;) and two oak species (&lt;em&gt;Quercus&lt;/em&gt; &lt;em&gt;petraea&lt;/em&gt; and &lt;em&gt;Quercus pyrenaica&lt;/em&gt;) were added to a Portuguese red wine. Various global phenolic parameters of red wines were studied during the aging process (90 storage days). In addition, a sensory analysis was made after the 90-day aging period to determine the impact of the use of different wood chip species on red wine sensory profile. The results showed that during the aging period, only a few differences were detected between the wines. However, after 90 aging days, in general the wines aged in contact with cherry wood tended to have the lowest values for several phenolic parameters. For sensory parameters, the wine aged in contact with French oak chips showed significantly higher scores for several aroma descriptors, while for visual and taste descriptors no statistical significant differences were found between the wines.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Conclusion:&lt;/strong&gt; At the concentration used (3 g wood chips/L wine), the different wood chip species studied had no clear influence on the evolution of the majority of the red wine phenolic parameters. However, from a sensory point of view, the use of different wood species induced greater differentiation, especially for aroma descriptors.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Significance and impact of the study:&lt;/strong&gt; The outcomes of this study would be of practical interest to winemakers and regulatory institutions since they could improve the knowledge of the impact of alternative wood chip species, namely acacia and cherry, on red wine quality.&lt;/p&gt;

A full factorial study on the effect of tannins, acidity, and ethanol on the temporal perception of taste and mouthfeel in red wine

Wine is a globally appreciated alcoholic beverage, with complex sensory properties. Ethanol, acid and tannin play a primary role in the aroma, taste and mouthfeel perception of wine, and ultimately on product liking. This study utilized a factorial design to explore the relationship among these factors in Merlot wine. The design encompassed three acid concentrations: 5, 6, 7g/L tartaric acid eq., three ethanol concentrations: 14, 14.5, 15% (v/v), and two tannin concentrations: low (approx. 700mg/L CE), and high (approx. 1200mg/L CE). The 18 wines were achieved through post fermentation additions of tartaric acid and water. Descriptive analysis (DA) and temporal dominance of sensation (TDS) were applied to profile static and temporal sensory perception. Descriptive analysis (DA) was used to asses 16 aroma, 4 mouthfeel, and 3 taste attributes. The evaluated factors showed no impact on the 16 aroma descriptors. Tannin concentration showed the greatest impact on taste and mouthfeel, significantly increasing sourness, bitterness, astringent texture, drying, and overall astringency. Acid concentration significantly increased the perception of sourness, while decreasing bitterness. Ethanol concentration was not a significant source of variation within the descriptive analysis. A novel way of analyzing TDS curves was applied, based on the factorial design, which allows for the temporal effect of specific factors to be studied. Wines were grouped by factor followed by TDS curve construction. Both normalized and standard TDS curves were constructed. Normalization captured the initial dominant perception, while standardized curves show the decline in dominance as the evaluation proceeds. Overall, the data demonstrates the dominance of astringency over multiple red wine taste factors.

Is coronene better described by Clar's aromatic π-sextet model or by the AdNDP representation?

The bonding patterns in coronene are complicated and controversial as denoted by the lack of consensus of how its electronic structure should be described. Among the different proposed descriptions, the two most representative are those generated by Clar's aromatic π-sextet and adaptative natural density partitioning (AdNDP) models. Quantum-chemical calculations at the density functional theory level are performed to evaluate the model that gives a better representation of coronene. To this end, we analyse the molecular structure of coronene, we estimate the aromaticity of its inner and outer rings using various local aromaticity descriptors, and we assess its chemical reactivity from the study of the Diels-Alder reaction with cyclopentadiene. Results obtained are compared with those computed for naphthalene and phenanthrene. Our conclusion is that Clar's π-sextet model provides the representation of coronene that better describes the physicochemical behavior of this molecule. © 2017 Wiley Periodicals, Inc.

Bioactives, Aromatics and Sensory Properties of Cold‐Pressed and Hexane‐Extracted Lemon (Citrus Limon L.) Seed Oils

AbstractThe objective of this study was to provide more essential data about the bioactive, aromatic volatile composition and sensory properties of lemon seed oils to possibly establish new application areas of this unexplored new oil. Furthermore, cold pressing and hexane extraction were compared. Catechin, eriocitrin, rutin, naringin, naringenin, hesperidin, neohesperidin and kaempherol as flavonoids, and gallic, syringic, tr‐ferulic, rosmaniric and tr‐2‐hydrocinnamic acids as phenolic acids were quantified in the oils. Naringin, gallic and syringic acids were significantly higher in the cold‐pressed sample. Around 30 different aromatic volatiles were identified in both samples, and, for the majority, the concentrations were higher in the cold‐pressed sample. It was observed that lemon seed oil is very aromatic, mostly characterized by citrus, herbal, terpenic, woody, and floral aroma descriptors. A panel evaluated the oils for sensory properties with 13 different definition terms (clarity, lemon peel, roasted, raw vegetable, grassy, bitter, astringent, waxy, nutty, fatty, spicy and throat‐catching). The oil was defined as very bitter, astringent, spicy and throat‐catching. In conclusion, lemon seed oil was found unsuitable for direct edible use, but might be preferable for its unique aroma and bioactive components for functional food, pharmaceutical and cosmetic applications.

The flavor and taste of cereal Chinese vinegars

A lexicon for describing Chinese cereal vinegars (CCVs) was developed using trained panels of tasters that defined and referenced 23 significant olfactory descriptors, in concert with taste and trigeminal sensation. The sensory analysis was performed on 27 samples, representative of the five well-known Chinese provinces producing vinegar: Shanxi, Jiangsu, Sichuan, Fujian and Tianjin. Several aromatic descriptors define the sensory lexicon, e.g.: licorice, chocolate, meat broth, toasted, walnut, yogurt, coffee; together with five basic tastes, such as acid, sweet, salty, umami and bitter; and four for trigeminal sensations, astringent, pungent, metallic, and piquant (spicy). This preliminary study will be useful to CCVs producers because this lexicon reliably differentiates and characterizes this kind of vinegar.

Wine-making with Protection of Must against Oxidation in a Warm, Semi-arid Terroir

To protect varietal aromas from oxidation before alcoholic fermentation, two grape must samples were prepared from white grapes potentially low in copper, pre-cooled and supplemented with ascorbic acid and solid CO2 (trial ACO2) or SO2 (trial BSO2). The wines prepared from musts protected from oxidation had aroma descriptors that included “passion fruit” and “grapefruit skin”. The lower concentrations of flavanols in the ACO2 trial demonstrated that the use of solid CO2 as an oxidation preventative instead of SO2 reduced the extraction of these polyphenols from the grape solids. The higher concentration of hydroxycinnamoyl tartaric acids of the wine from the A CO2 trial with respect to BSO2 was ascribed to the lower grape polyphenoloxidase activity induced by the lower oxygen level in the A CO2 trial, or to the combination of caftaric acid quinone with the SO2 in B SO2. Although the grapes were very ripe (alcohol in wines ~ 14.5% vol), the wines made with musts prepared by the two techniques were characterised by aroma descriptors like “passion fruit” and “grapefruit skin”, and these aromas were not detected in the wines prepared from unprotected musts.

Comparison of Volatile Compounds in Two Brandies Using HS-SPME Coupled with GC-O, GC-MS and Sensory Evaluation

The aim of this study was to compare the volatile compounds between Changyu XO and Hennessy XO. Sensory evaluation was performed by a panel of tasters. Qualitative and semi-quantitative analysis was achieved by headspace solid phase micro-extraction (HS-SPME), coupled with gas chromatography-mass spectrometry (GCMS) and gas chromatography-olfactometry (GC-O). A total of 160 volatile compounds were identified in the two brands of brandy. Of these, 118 compounds were common to both Changyu XO and Hennessy XO; 18 compounds were specific to Changyu XO and 24 were specific to Hennessy XO. A total of 85 aroma compounds responsible for brandy flavour were identified by GC-O, of which 68 were common to both brands, while seven and ten were specific to Changyu XO and Hennessy XO, respectively. The study provided detailed information about the compounds responsible for the characteristic flavour of specific brandies. According to statistical analysis, significant differences were recorded between Changyu XO and Hennessy XO. Most volatile compounds in Changyu XO occurred at lower concentrations than those in Hennessy XO. Based on sensory evaluation analysis, the floral, alcohol and rancid aroma descriptors achieved higher scores in Changyu XO and Hennessy XO, while the lime aroma seemed specific to Hennessy XO. Herb and almond aromas were specific to Changyu XO.

Aroma Characterization of Petit Manseng Wines Using Sensory Consensus Training, SPME GC-MS, and Electronic Nose Analysis

The aromas of four Virginia Petit Manseng wines were evaluated using sensory consensus training methods, and results were compared to those of solid-phase microextraction gas chromatography-mass spectrometry (GC-MS) and conducting polymer electronic nose (ENose) analysis of volatile compounds. Five sensory training sessions were conducted to enhance aroma identification, evaluate aroma intensity, and teach evaluation techniques to a panel of 13 individuals. Ten aroma descriptors were determined to describe the commercial wines: pear, peachy, floral, melon, exotic fruits, estery, vanilla, citrus, and honey. The four wines differed significantly (p