Influence of oak maturation regimen on composition, sensory properties, quality, and consumer acceptability of cabernet sauvignon wines

Consumer perspectives of wine typicity and impact of region information on the sensory perception of Cabernet Sauvignon wines

Region of origin is used in marketing of wine and by consumers as a wine quality indicator. To better understand wine consumers' purchase decisions, sensory perception, and wine liking in connection with wine provenance, this study used regular wine consumers (n = 112) to evaluate two Cabernet Sauvignon wines from each of four wine producing regions through hedonic rating and rate-all-that-apply (RATA) testing in conjunction with pre- and post-tasting questionnaires. The majority of consumers rated the region of origin stated on the label as important for purchase intent and for deciding the price they were willing to pay for a wine. The questionnaire also revealed that consumers were familiar with the wine typicity concept, but seemed to consider it only as an extrinsic characteristic rather than an intrinsic aspect of the wine. By randomly dividing the consumers into two groups (n = 56 each), one having information on the origin of samples and the other tasting without such knowledge, it was demonstrated that origin information had a positive impact on hedonic scores. Sensory profiling revealed that origin information did not impact the sample sensory characterisation, and liking for both groups was related to 'full body', 'jammy', and 'dark fruits' attributes. Some regional profile features were apparent for the samples, such as 'minty' for Coonawarra and savoury attributes for Bordeaux. Overall, this work highlighted that consumers could differentiate wines from distinct regions on the basis of sensory characteristics.

Investigation of Volatile Compounds, Microbial Succession, and Their Relation During Spontaneous Fermentation of Petit Manseng

Petit Manseng is widely used for fermenting sweet wine and is popular among younger consumers because of its sweet taste and attractive flavor. To understand the mechanisms underlying spontaneous fermentation of Petit Manseng sweet wine in Xinjiang, the dynamic changes in the microbial population and volatile compounds were investigated through high-throughput sequencing (HTS) and headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) technology, respectively. Moreover, the relationship between the microbial population and volatile compounds was deduced via multivariate data analysis. Candida and Mortierella were dominant genera in Petit Manseng wine during spontaneous fermentation. Many fermentative aroma compounds, including ethyl octanoate, isoamyl acetate, ethyl butyrate, ethyl decanoate, isoamyl alcohol, ethyl laurate, isopropyl acetate, hexanoic acid, and octanoic acid, were noted and found to be responsible for the strong fruity and fatty aroma of Petit Manseng sweet wine. Multivariate data analysis indicated that the predominant microorganisms contributed to the formation of these fermentative aroma compounds. Hannaella and Neomicrosphaeropsis displayed a significantly positive correlation with the 6-methylhept-5-en-2-one produced. The current results provide a reference for producing Petit Manseng sweet wine with desirable characteristics.

Differences in Astringency Subqualities Evaluated by Consumers and Trained Assessors on Sangiovese Wine Using Check-All-That-Apply (CATA)

The astringency of red wine represents an important factor of quality and liking evaluation by consumers, but it is sometimes associated to a negative feature. We studied the differences in astringency subqualities of Sangiovese wines between consumers and trained assessors. Wines belonging to three denominations (Chianti Classico, Toscana, Morellino di Scansano) and a Chianti Classico specification (Chianti Riserva), from three price ranges (low, medium, high) were evaluated. Regular wine consumers and trained panel assessed the wines applying the Check-All-That-Apply (CATA) questionnaire relative to six astringency attributes (silk, velvet, dry, aggressive, hard, mouthcoat). Differences between panels were more associated with the high-price wines, which were characterised by negative subqualities for consumers. Preference maps revealed that mouthcoat was the term mainly associated with consumers’ liking, while other subqualities as persistent, rich, and full-body, provided by the trained assessors, may represent the drivers of liking for Sangiovese wine. This study has demonstrated that a trained sensory panel provides highly valuable information regarding the mouthfeel characteristics of Sangiovese wines and the attributes driving consumer liking.

Sensory typicity of regional Australian Cabernet Sauvignon wines according to expert evaluations and descriptive analysis

The concept of wine typicity has been an important tool for the international wine trade, and especially for Old World wine producing countries, where provenance criteria are regulated and act as a quality indicator. Provenance in Australia is governed by Geographical Indications, for which typicity should also be evident in terms of regional sensory profiles of wine from a given grape cultivar. Two approaches were used to identify sensory drivers for regional typicity of commercial Cabernet Sauvignon wines from three Australian regions, namely Coonawarra, Margaret River, and Yarra Valley. Cabernet Sauvignon-dominant wines from Bordeaux were also assessed for benchmarking purposes. A set of 84 wines underwent a sorting task and rate-all-that-apply (RATA) analysis of the sorted groups with an expert panel. Agglomerative hierarchical clustering of the sorting task data did not show a clear regional driver upon separating the samples into four main clusters, although certain sensory traits could be associated with the different clusters. On the other hand, canonical variate analysis (CVA) of the group-RATA results indicated several sensory drivers for the separation between the regions, such as 'mint' and 'dark fruits' being important for Coonawarra wine profiles, 'floral' and 'green pepper' for Margaret River, 'stemmy' for Yarra Valley, and 'barnyard' and 'savoury' differentiating Bordeaux wines from the other regions. A subset (n = 52) of wines was selected for further evaluation by descriptive analysis with a trained panel. Statistical evaluation with CVA revealed similar results to the expert evaluation, with Bordeaux wines showing more dissimilarity when compared to Australian regions, and having 'savoury' and 'earthy' as significant characters. The results also demonstrated that 'mint' and 'Mallee leaf' were relevant characters for Coonawarra regional sensory profile, 'violets' and 'red fruits' for Margaret River, and 'cooked vegetables' for Yarra Valley. Analysing both data sets (expert RATA and DA) revealed some agreement between the sets of results for attributes such as 'mint', 'cooked vegetables', 'floral', green-related characters, and oak characters like 'vanilla' and 'chocolate'. Overall, experts and trained panellists were able to distinguish regions based on a few characteristic sensory traits.

The Effect of Different Oak Products Used during Fermentation and Ageing on the Sensory Properties of a White Wine over Time

The sensorial evaluation of Chenin blanc wine produced with different types of oak wood treatments over time has not been investigated before. The main aim of this study was to assess the sensory profile, using a trained panel, of a South African Chenin blanc wine fermented and matured in old barrels, three types of new oak barrels, two types of oak staves as well as a stainless steel tank over time, which has not been done before. Results indicate mainly separation between the stainless-steel tank/old barrel treatments from the stave and new barrel treatments, with separation between the latter two treatments also being found. More fruity descriptors were used in the stainless-steel tank and old barrel treatments, with oak-related descriptors being used in the stave and new barrel treatments. Separation between among the new barrel and stave treatments were also noted, which was still reflected during bottle maturation. These results indicate that winemakers need to take cognizance of the sensorial differences induced by barrel and stave maturation in white wines and how these evolve over time.

Using Content Analysis to Characterise the Sensory Typicity and Quality Judgements of Australian Cabernet Sauvignon Wines

Understanding the sensory attributes that explain the typicity of Australian Cabernet Sauvignon wines is essential for increasing value and growth of Australia’s reputation as a fine wine producer. Content analysis of 2598 web-based wine reviews from well-known wine writers, including tasting notes and scores, was used to gather information about the regional profiles of Australian Cabernet Sauvignon wines and to create selection criteria for further wine studies. In addition, a wine expert panel evaluated 84 commercial Cabernet Sauvignon wines from Coonawarra, Margaret River, Yarra Valley and Bordeaux, using freely chosen descriptions and overall quality scores. Using content analysis software, a sensory lexicon of descriptor categories was built and frequencies of each category for each region were computed. Distinction between the sensory profiles of the regions was achieved by correspondence analysis (CA) using online review and expert panellist data. Wine quality scores obtained from reviews and experts were converted into Australian wine show medal categories. CA of assigned medal and descriptor frequencies revealed the sensory attributes that appeared to drive medal-winning wines. Multiple factor analysis of frequencies from the reviews and expert panellists indicated agreement about descriptors that were associated with wines of low and high quality, with greater alignment at the lower end of the wine quality assessment scale.

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.

High-throughput sequencing of microbial community diversity in soil, grapes, leaves, grape juice and wine of grapevine from China

In this study Illumina MiSeq was performed to investigate microbial diversity in soil, leaves, grape, grape juice and wine. A total of 1,043,102 fungal Internal Transcribed Spacer (ITS) reads and 2,422,188 high quality bacterial 16S rDNA sequences were used for taxonomic classification, revealed five fungal and eight bacterial phyla. At the genus level, the dominant fungi were Ascomycota, Sordariales, Tetracladium and Geomyces in soil, Aureobasidium and Pleosporaceae in grapes leaves, Aureobasidium in grape and grape juice. The dominant bacteria were Kaistobacter, Arthrobacter, Skermanella and Sphingomonas in soil, Pseudomonas, Acinetobacter and Kaistobacter in grape and grapes leaves, and Oenococcus in grape juice and wine. Principal coordinate analysis showed structural separation between the composition of fungi and bacteria in all samples. This is the first study to understand microbiome population in soil, grape, grapes leaves, grape juice and wine in Xinjiang through High-throughput Sequencing and identify microorganisms like Saccharomyces cerevisiae and Oenococcus spp. that may contribute to the quality and flavor of wine.