Rosé wine volatile composition and the preferences of Chinese wine professionals

Characterization of benzenemethanethiol in sesame-flavour baijiu by high-performance liquid chromatography-mass spectrometry and sensory science

Chinese sesame-flavour baijiu (CSB) is one of aroma types discovered after the founding of China. Sulfur-containing compounds have low content in CSB but play an important role. This study developed a quantitative method by derivatization reaction combined LC-MS/MS for the determination of benzenemethanethiol (BM), which has a roasted aroma in CSB. Under the optimized conditions, the LOD and LOQ of BM were 11.73 ng L^-1 and 39.09 ng L^-1, respectively. The recovery yield of the derivatization product ranged from 82.12% to 93.99%. The content of BM in 4 CSBs were 150.22-860.40 ng L^-1. To confirm the contribution of BM to the overall aroma of CSB, aroma recombination experiments and omission experiments were carried out. Compared with that of the simulated baijiu sample without BM, the roasted aroma of the simulated baijiu sample containing BM was enhanced. Omission experiments showed that BM made important contributions to the overall aroma of CSB.

Impact of Different Stoppers on the Composition of Red and Rosé Lagrein, Schiava (Vernatsch) and Merlot Wines Stored in Bottle

Different technical cork stoppers (blend of natural cork microgranules, one-piece natural cork, agglomerated natural cork, technical cork 1+1) were compared to evaluate the effects on the phenolic, volatile profiles and dissolved oxygen in three red (Merlot, Lagrein red, St. Magdalener) and one rosé (Lagrein rosé) wines, which were stored in bottles for 12 months. Gallic acid, caffeic acid, p-coumaric acid, trans-resveratrol, glutahionyl caftaric acid and protocatechuic acid did not vary remarkably during the first three months, whereas at six months a net increase was reported, followed by a clear decrease at 12 months. The same trend was observed in Lagrein rosé, but only for gallic acid. The total anthocyanins content decreased during the storage period in the four wines. Isopentyl acetate, 1-hexanol, ethyl hexanoate, 2-phenylethyl alcohol, diethyl succinate, ethyl octanoate and ethyl decanoate were the main volatile compounds. The sum of alcohols decreased in all four of the wines. The esters decreased in Merlot; however, they increased in Lagrein rosé, Lagrein red and St. Magdalener during the storage. Univariate and multivariate statistics and a sensory discriminant triangle test displayed similar influences of the different stoppers on the phenolic and volatile compounds during the whole storage duration. The changes detected in the phenolic and volatile concentrations were presumably due to the non-oxygen-mediated reactions occurring during 12 months of storage in bottle.

Consumers Associate High-Quality (Fine) Wines with Complexity, Persistence, and Unpleasant Emotional Responses

The conventional method for the sensory evaluation of wine is based on visual, olfactory and gustatory perceptions described by a domain-specific language. This is a complex task, requiring extensive training, which is not feasible from a consumer perspective. The objective of this study was to apply a wine tasting sheet, including sensory and emotional responses, to simplify the recognition of fine white wines by consumers. First, a panel of 15 semi-trained judges evaluated eight sensory attributes through Optimized Descriptive Profile (ODP) methodology. Then, a group of 104 consumers evaluated five white wines with different sensory characteristics using an improved emotional wine tasting sheet. The emotions and sensations most frequently associated with white wines were obtained through the Check-All-That-Apply (CATA) approach. The eight sensory attributes were significant (p-value < 0.05) in the distinction of wines by the ODP. Likewise, the distinction of the wines also provided significant differences in all the emotional and sensory attributes (p-value < 0.05). The different wine styles could be distinguished by Principal Component Analysis (PCA) using the semi-trained judges or the consumer responses. The highest score in the “global evaluation” was given to two young, fruity wines characterized by high aromatic “initial impression”. The two fine wines, including a 2004 Burgundy Pouilly-Fuissé, were the lowest rated in “initial impression” and “global evaluation”, although they were considered by the consumers among the most complex and persistent. These wines were also most frequently associated with unpleasant emotions by the CATA test. The recognition of these fine wine attributes and their incongruity with emotional responses can be used in a rapid way by professionals to explain the different wine styles to consumers.

A matter of place: Sensory and chemical characterisation of fine Australian Chardonnay and Shiraz wines of provenance

Establishing a fine wine image through regional typicality has been of interest to New World wine producing countries like Australia, but previous research mainly involved unoaked experimental wines, which were not reflective of the retail wine market. The regional typicality of commercially available fine Australian wines (FAW) was therefore explored, based on the hypotheses that sensory and chemical composition of varietal fine wines would discriminate by region, and further nuances within region would be explained by drivers of intraregional typicality. Chardonnay wines (2015 vintage) from Margaret River (MR, n = 16) and Yarra Valley (YV, n = 16); and Shiraz wines (2014 vintage) from Barossa Valley (BV, n = 16) and McLaren Vale (MV = 15), were selected for descriptive sensory analysis and underwent profiling of volatiles by gas chromatography-mass spectrometry (GC-MS). For both grape varieties, there was large variability in wine styles among wines from the same GI, such as fruity/crisp vs oaked Chardonnay and oaky/astringent vs savoury Shiraz. Consequently, human intervention seemed to be an important component of regional/sub-regional typicality, which therefore cannot be determined solely on geographic origin of the fruit. Using a combination of sensory markers and volatile profiles allowed the building of regional typicality models, which are promising, however, consumers may not perceive sub-regional differences based on sensory attributes. Undoubtedly, variation of wine styles emerging across wine regions, vintages, and viticultural and winemaking practices needs to be further explored, but this work created a preliminary sensory and volatile map for future research.

Volatile Composition and Sensory Profiles of a Shiraz Wine Product Made with Pre- and Post-Fermentation Additions of Ganoderma lucidum Extract

Novel Shiraz red wine products enriched with Ganoderma lucidum (GL) extract, a traditional Asian medicinal mushroom, were developed and characterized. GL extract was added at different levels prior to and after primary fermentation to investigate its impact on the juice fermentation kinetics, and the chemical composition and sensory properties of the resulting wines. The fermentation kinetics of red grape juice were not significantly different between ferments. Basic chemical analyses plus headspace solid-phase micro-extraction (HS-SPME), gas chromatography‒mass spectrometry (GC-MS), and a rate-all-that-apply (RATA) (n = 65) sensory panel were used to investigate the influence of GL extract additions on wine composition and sensory characteristics. Of the 54 sensory attributes assessed, 39 significantly differentiated the wines. A clear separation between GL wine treatments was evident with PLS regression, where specific volatiles were correlated with relevant sensory attributes that dominated the wines. These products could be promising for emerging wine markets.

Investigating caloric values and consumers' perceptions of Nova Scotia rosé wines

In Nova Scotia, Canada, wine production has been increasing, yet little research has been done to identify and classify the sensory properties of Nova Scotia (NS) rosé wines. The first objective of this study was to identify the attributes consumers use to describe NS rosé wines. The second aim was to identify if presenting caloric labels on wine bottles would impact consumers' sensory perception. The first trial asked consumers (n = 85) to use projective mapping (PM) and ultra-flash profiling (UFP) to describe NS rosé wines (n = 8). In the second trial, consumers (n = 260) were asked to complete a check-all-that-apply (CATA) questionnaire, using the most frequently cited attributes from the PM and UFP trial, and to score their liking on 9-point hedonic scales (n = 4). Each wine was evaluated without a label and with each of the four fabricated caloric values, low (15 Calories), normal (100 Calories), high (180 Calories), and highest (240 Calories) per one serving. The projective mapping trial found that there were two main categories of rosé wines identified by consumers, those with fruit flavour and those lacking in fruit flavour. The penalty analysis from the consumer trial demonstrated that fruit attributes drove consumer liking of rosé wine. The consumer trial also displayed no significant difference between the caloric value and liking of rosé wines, even when the results were separated based on gender. Therefore, the findings support that the disclosure of caloric values on bottles will not influence consumers' sensory perceptions of wine. For future research, complete nutrition labels and not just calories alone should be used to determine their effect on consumers' perceptions.

Comprehensive Study of Volatile Compounds in Two Australian Rosé Wines: Aroma Extract Dilution Analysis (AEDA) of Extracts Prepared Using Solvent-Assisted Flavor Evaporation (SAFE) or Headspace Solid-Phase Extraction (HS-SPE)

Two rosé wines, representing a tropical and a fruity/floral style, were chosen from a previous study for further exploration by aroma extract dilution analysis (AEDA) and quantitative analysis. Volatiles were extracted using either liquid-liquid extraction (LLE) followed by solvent-assisted flavor evaporation (SAFE) or a recently developed dynamic headspace (HS) sampling method utilizing solid-phase extraction (SPE) cartridges. AEDA was conducted using gas chromatography-mass spectrometry/olfactometry (GC-MS/O) and a total of 51 aroma compounds with a flavor dilution (FD) factor ≥3 were detected. Quantitative analysis of 92 volatiles was undertaken in both wines for calculation of odor activity values. The fruity and floral wine style was mostly driven by 2-phenylethanol, β-damascenone, and a range of esters, whereas 3-SHA and several volatile acids were seen as essential for the tropical style. When extraction methods were compared, HS-SPE was as efficient as SAFE for extracting most esters and higher alcohols, which were associated with fruity and floral characters, but it was difficult to capture volatiles with greater polarity or higher boiling point that may still be important to perceived wine aroma.