Blended Wines Research Articles

Influence of Brettanomyces ethylphenols on red wine aroma evaluated by consumers in the United States and Portugal

Brettanomyces may add complexity to wine at low concentrations but at high concentrations, can result in objectionable wines. The objective of this study was to determine the concentrations at which consumers from two different locations were able to detect Brettanomyces volatile compounds present in a red wine. A red wine blend, used in both countries, was spiked to create five treatments containing different concentrations of 4-ethylphenol (4-EP), 4-ethylguiacol (4-EG), and 4-ethylcatechol (4-EC) in a 5:1:1 ratio, respectively. These treatments were evaluated by consumers in the United States and Portugal (n=121) using a difference from control test. Consumers were also classified as having low, medium, or high wine knowledge. Among the spiked samples, the greatest degree of difference was found between the second and third treatments, corresponding to reported detection and recognition threshold ranges of 4-EP and 4-EG. For some treatments, consumers from Portugal classified in the medium or high knowledge level reported significantly higher mean differences from the control than those in the low knowledge group (p<0.05). Results demonstrated consumers' ability to detect differences in red wines due to Brettanomyces volatile compounds. Results provide useful context on how wine knowledge and cultural variants may affect the detection of Brettanomyces.

From wine to hollandaise sauce: Does the nature of the wine or wine reduction influence sensory attributes?

Wine is often used as an ingredient in butter sauces such as hollandaise sauce, but normally in its reduced form. Hollandaise sauce is an emulsion, and roughly consists of a continuous phase (water based ingredients) and a dispersed phase (fat). In addition, hollandaise sauce contains varying amounts of incorporated air, seen as air bubbles in the sauce. In this study, the influence of wines and wine reductions on sauce flavor was studied. Butter sauces, where the aqueous phase of the sauces varied, were made and analyzed. Four different types of white wine (Chardonnay, Riesling, Sauvignon blanc and a blended wine) and these wines’ corresponding wine reductions were incorporated in butter sauce to produce model products (eight sauces in total). In the reductions, approximately 51% of the volume was removed by evaporation. The wines were selected based on both non-volatile composition and aroma differences. A trained sensory panel (n=10) evaluated sauce flavor and texture. Volatile profiles of sauces were studied by GC-MS, and sauce texture was evaluated by texture analysis, microscopy and dry matter measurements. Results showed that the degree of reduction is more important for sauce flavor than the wine type.

The Phenolic Composition of South African Pinotage, Shiraz and Cabernet Sauvignon Wines

Phenolic compounds are major constituents of red wines and impact on certain wine-quality parameters. This study has aimed to increase the knowledge base on the phenolic composition of South African red wines by HPLC quantification of 39 individual phenols and 2 polymeric, phenolic groups in 260 South African wines of the cultivars Pinotage, Shiraz and Cabernet Sauvignon. Statistical analysis of the collected data revealed significant cultivar differences in the levels of many of the analysed compounds, as well as in the ratios in which specific anthocyanins are found in the wines. These data may be helpful in the cultivar authentication of wines of these cultivars. Discriminant analysis of the data showed statistically significant separations of cultivars, based on their polyphenol composition, and also how the use of data from a specific wine-producing area or vintage improved the possibilities for successful authentication. The data were collected from both pure cultivar wines and commercial wines, which may contain up to 15 % of another cultivar wine. The collected data may therefore be further segmented into those obtained from pure cultivar wines and those obtained from blended wines in order to further enhance the accuracy of authentication of these respective groups of wines. The information obtained from this study opens several avenues for research on the impact of the noted cultivar differences on wine quality. Cultivar differences in the phenolic composition of young red wines also have important implications for the oenological management of oxidation reactions taking place during vinification and aging.

Effect of Bunch Removal on Grape Composition and Wine Quality of Vitis vinifera L. cv. Chardonnay

To determine whether grape composition and wine quality of premium wine grape cultivars in South Africa would be improved when certain degrees of bunch removal are applied at a later stage than 14°B and when all treatments are harvested at approximately the same sugar content, one-third and two-thirds of the bunches of Chardonnay were removed at l 7°B and 19°B in a field trial at Robertson for three consecutive seasons (1990 - 1993). In addition to these four treatments, a control treatment (no bunch removal) and a treatment where bunches were harvested on the sunny and shaded sides of the same canopy (without prior bunch removal) at approximately 21,5°B were also included in the study. The economic use of removed grapes was determined, whereas all factors, including additional labour costs, were taken into account to establish whether bunch removal is an economically viable practice. A maximum reduction in yield of 11,6 t ha-' compared to that of the control was obtained when two-thirds of the bunches were removed at 19°B. No measurable compensation in berry mass occurred when bunches were removed at l7°B and 19°B. Grapes removed at 17°B and 19°B were suitable for the making of distilled and sparkling wine or for use in wine blends and thus contributed to the total income of the vineyard. Bunch removal did not improve must and wine composition. Few differences in the concentrations of individual sugar and organic acids in the grapes, and volatile acid, alcohol and ester compounds in the wines were obtained. Wine of treatments where bunches were removed tended to be of lower quality. No improvement in wine quality was found with differential harvesting on the sunny and shaded sides of the canopy. Bunch removal was labour intensive and not economically viable.

Effect of different wood chips on physico-chemical and sensory quality attributes of bitter gourd-grape blended wine during maturation

Bitter gourd (Momordica charantia) used as a medicinal herb as anti-HIV, anti-ulcer, antiinflammatory, antileukemic, anti-microbial, antidiabetic and anti-tumer. So it can be used to prepare different processed products including beverages. Preparation of alcoholic beverages including wine is one of the options available. As bitter gourd fruit is bitter in taste so the wine is also expected to be bitter, thus a combination of bitter gourd with some suitable fruit holds promise to make a patable yet retaining the product with medicinal properties. Bitter gourd-grape wine (60% bitter gourd juice 40% grape juice) was matured for 3 months with wood chips of Quercus, Acacia and Bombax spp. (2.5 g/l of wine). A decrease in TSS (3.50 to 3.0%), total sugar (0.730 to 0.710%), titratable acidity (0.64 to 0.59%), ethanol level (3.82 to 3.69%) and colour O.D. (0.301 to 0.298) was recorded during maturation while increase in higher alcohol (48.10 to 55.00 mg/l) and antioxidant activity (67.91 to 68.60%) was observed. On the basis of various physico-chemical and sensory characteristics, bittergourd grape wine matured with Quercus spp. wood chips for 3 months was the best, followed by Acacia ssp.

Piperitone Profiling in Fine Red Bordeaux Wines: Geographical Influences in the Bordeaux Region and Enantiomeric Distribution.

Piperitone was recently identified in red Bordeaux wines, and this study was designed to further explore its contribution to wine aroma. Firstly, a geographical origin effect was detected within the Bordeaux region (left versus right banks of the Gironde estuary), with significantly higher mint aroma intensities and piperitone levels in wines from the left bank (Medoc appellations). Statistical analysis of chemical and sensory data highlighted a correlation with the proportion of Cabernet Sauvignon in the wine blends. Accordingly, it was suggested that these sensory and chemical differences may be of varietal origin. Secondly, the contribution of piperitone to minty aromas in the aging bouquet was confirmed by combining both sensory and chemical data from a wide range of red Bordeaux wines. Subsequent investigation of the enantiomeric distribution of piperitone found a significantly higher proportion of the (+)-(6S) enantiomeric form in wines displaying a strong aging bouquet.

Experimental Review of DNA-Based Methods for Wine Traceability and Development of a Single-Nucleotide Polymorphism (SNP) Genotyping Assay for Quantitative Varietal Authentication

The genetic varietal authentication of wine was investigated according to DNA isolation procedures reported for enological matrices and also by testing 11 commercial extraction kits and various protocol modifications. Samples were collected at different stages of the winemaking process of renowned Italian wines Brunello di Montalcino, Lambruschi Modenesi, and Trento DOC. Results demonstrated not only that grape DNA loss is produced by the fermentation process but also that clarification and stabilization operations contribute to the reduction of double-stranded DNA content on wine. Despite the presence of inhibitors, downstream PCR genotyping yielded reliable nuclear and chloroplast SSR markers for must samples, whereas no amplification or inconsistent results were obtained at later stages of the vinification. In addition, a TaqMan genotyping assay based on cultivar-specific single-nucleotide polymorphisms (SNPs) was designed, which allowed assessment of grapevine DNA mixtures. Once the wine matrix limitations are overcome, this sensitive tool may be implemented for the relative quantification of cultivars used for blend wines or frauds.

Flavoured Wine – Fad, Fashion or Trend?

This project was initiated because of the increased diversity in demand across global wine markets. Traditional wine producing countries have experienced strong, recent growth in new categories like flavoured wines, while New world countries create publicity for such innovations and traditional categories like organic wines. Ironically, the amount of publicity afforded such categories is contradictory to market trends, which illustrate growth in categories like Prosecco and red wine blends. Categories like organic, natural and orange wine have numerous endorsers, but actual sales figures suggest such wines are yet to capture the interest of the greater market.With this divergence between publicity and market behaviour being echoing across the globe, wine producers need to be able to determine whether a new category represents an opportunity to consider a strategic change in business direction. Although publicity has been shown to effect a change in wine consumer behaviour, the conditions surrounding a new wine category's growth from fad, trend and fashion are analysed for the purpose of strategic management. This study extends findings from historical narratives through the use of empirical evidence from both European and New World wine markets. The evidence is contrasted with a contemporary phenomenological experience expressed by influencers within both of those markets, as a means to illustrate the disparity between the contemporary appeal of popular publicity, and the challenges faced by wine producers having to respond to the market reality. This study illustrates that implementing strategic decisions on whether to engage in a new trend, depends on the innovative category being consistent with existing strategy and able to impact the market without reliance on external publicity.

Constrained global optimization for wine blending

Assemblage consists in blending base wines in order to create target wines. Recent developments in aroma analysis allow us to measure chemical compounds impacting the taste of wines. This chemical analysis makes it possible to design a decision tool for the following problem: given a set of target wines, determine which volumes must be extracted from each base wine to produce wines that satisfy constraints on aroma concentration, volumes, alcohol contents and price. This paper describes the modeling of wine assemblage as a mixed constrained optimization problem, where the main goal is to minimize the gap to the desired concentrations for every aromatic criterion. The deterministic branch and bound solvers Couenne and IbexOpt behave well on the wine blending problem thanks to their interval constraint propagation/programming and polyhedral relaxation methods. We also study the performance of other optimization goals that could be embedded in a configuration tool, where the different possible interactions amount to solving the same constraints with different objective functions. We finally show on a recent generic wine blending instance that the proposed optimization process scales up well with the number of base wines.

Chemometric and phenolic attributes of blended wines assessed by multivariate techniques

The aim of the study was to investigate the quality of blended wines produced from Vitis vinifera L. Cabernet Sauvignon, Merlot and Sauvignon blanc grapes. Wines were processed according to accepted conventional methods for white and red wines. Blended wines were produced with different ranges (25, 50, 75 and 100%) of Cabernet Sauvignon, Merlot and Sauvignon blanc wines. Produced wines were evaluated for total phenols (mg/L), total tartaric esters (mg/L caffeic acid), total flavonols (mg/L quercetin), chemometric parameters such as D280%, D420%, D520%, D620%, dA%, CD%, T, CI%, R%, Y% and B%, CIELAB parameters, protein, total and volatile acidity. Analyses on an n-dimensional scale demonstrated the relationships among the wines of different grape origins and different blending ratios. On the basis of these differences, two main groups were plotted using principal component analysis and cluster analysis. The results demonstrate the possibilities of optimizing wines on the basis of defined parameters. Copyright © 2015 The Institute of Brewing & Distilling

Predicting the composition of red wine blends using an array of multicomponent Peptide-based sensors.

Differential sensing using synthetic receptors as mimics of the mammalian senses of taste and smell is a powerful approach for the analysis of complex mixtures. Herein, we report on the effectiveness of a cross-reactive, supramolecular, peptide-based sensing array in differentiating and predicting the composition of red wine blends. Fifteen blends of Cabernet Sauvignon, Merlot and Cabernet Franc, in addition to the mono varietals, were used in this investigation. Linear Discriminant Analysis (LDA) showed a clear differentiation of blends based on tannin concentration and composition where certain mono varietals like Cabernet Sauvignon seemed to contribute less to the overall characteristics of the blend. Partial Least Squares (PLS) Regression and cross validation were used to build a predictive model for the responses of the receptors to eleven binary blends and the three mono varietals. The optimized model was later used to predict the percentage of each mono varietal in an independent test set composted of four tri-blends with a 15% average error. A partial least square regression model using the mouth-feel and taste descriptive sensory attributes of the wine blends revealed a strong correlation of the receptors to perceived astringency, which is indicative of selective binding to polyphenols in wine.

Sensory and Chemical Effects of Cross-Flow Filtration on White and Red Wines

Cross-flow filtration is an increasingly common postfermentation process in the wine industry. Our hypothesis was that cross-flow filtration would not have a significant impact on the sensory or chemical properties of white or red wines because of the nature of the membranes used in this process. To investigate this, a California white wine blend and a California red wine blend were filtered in three 570 L lots using a Bucher Vaslin cross-flow unit with a nominal 0.22-micron polyethersulfone membrane. The unfiltered control was sent directly to the bottling line without filtration. Panelists evaluated the wines nine times during an eight-month descriptive analysis panel with replicated tasting at each time point. UV-vis spectrophotometry and the Adams–Harbertson assay were used to determine color and phenolic content of the filtered and unfiltered wines, respectively. The effect of filtration was significant for one sensory attribute out of 16 total measured in the white wine. Similar analysis indicated that six sensory attributes were significantly different out of 16 total in the red wine. Unfiltered red wines were higher in earthy, grassy, oak, and smoke aromas compared to filtered wines and lower in mixed berry and stone fruit aromas compared to the filtered wines, but only after two months in bottle. Cross-flow filtration was found to have a stabilizing effect on the sensory profile of both wines. For both wines there were significant changes in color and phenolic profile with filtration, but it is not clear, especially for red wines, whether the changes in phenolic compound concentration were great enough to be detected sensorially.

Phenolic composition and mouthfeel characteristics resulting from blending Chilean red wines

The blending of wine is a common practice in winemaking to improve certain characteristics that are appreciated by consumers. The use of some cultivars may contribute phenolic compounds that modify certain characteristics in blended wines, particularly those related to mouthfeel. The aim of this work was to study the effect of Carménère, Merlot and Cabernet Franc on the phenolic composition, proanthocyanidin profile and mouthfeel characteristics of Cabernet Sauvignon blends. Significant differences in chemical composition were observed among the monovarietal wines. Separation using Sep-Pak C₁₈ cartridges revealed differences in the concentration but not in the proportion of various proanthocyanidins. Blending reduced polyphenol concentration differences among the various monovarietal wines. Although no major overall differences were observed after blending the monovarietal wines, this oenological practice produced clear differences in mouthfeel characteristics in such a way that the quality of the perceived astringency was different. This study showed that the use of a particular wine variety (Cabernet Sauvignon) in a higher proportion in wine blending produced blends that were less differentiable from the monovarietal wine, owing to a suppression effect, producing an apparent standardization of the wines regarding chemical composition.

Assessment of competition in wine fermentation among wild Saccharomyces cerevisiae strains isolated from Sangiovese grapes in Tuscany region

In this study we analyzed Saccharomyces cerevisiae isolates obtained from spontaneous fermentations of grapes collected in one vineyard (same rows), during four harvest seasons (2006–2010). A total of 160 isolates were characterized by PCR amplification of inter-δ region. Six strains, representative of the different inter-δ profiles obtained, were tested in single and mixed fermentations at laboratory scale. In all the mixed fermentations, the strain possessing profile A (the only biotype found for two consecutive years) was tested in co-cultures with each of strains showing the other profiles. The strain “A” dominated in almost all the mixed fermentations. The experimental wines obtained from single and co-culture fermentations were analyzed for the content of main secondary compounds. The wines produced by mono-cultures were very different from the wines obtained by co-fermentations, except the wine by strain “A”, which grouped together with mixed-culture wines. Furthermore, the comparison between volatile components determined in mixed culture and blended wines, obtained by mixing monoculture wines, can suggest the existence of yeast metabolic interactions during mixed fermentations. The strain exhibiting the profile A resulted a good “competitor” not only among natural yeast population, but it was also capable to dominate mixed fermentations at lab scale.

Improvement in Quality of Wine by Blending White and Coloured Grapes

Blending of juices from four white grape varieties viz., Thompson Seedless, Chenin Blanc, Sauvignon Blanc and Italia with three coloured varieties, viz., Shiraz, Ruby Red and Bangalore Blue, was done in 2:1 and 3:1 ratios to assess the effect of blending on wine quality. White varieties blended with Bangalore Blue recorded maximum titratable acidity (1.23%), while those blended with Ruby Red showed the least acidity (0.42%), Alcohol content in the wine ranged from 8.11% (Italia + Ruby Red, 2:1) to 12.04% (Chenin Blanc + Shiraz, 2:1). The range of values for tannin content (0.007% to 0.044 %) and total phenol content (228mg/l to 571mg/l) indicated that white varieties blended with the coloured cv. Shiraz had the lowest content of tannins and total phenols in wine, while, those blended with cv. Ruby Red showed highest content of these in the blended wines. Hence, among different blends, Chenin Blanc, Thompson Seedless, Sauvignon Blanc and Italia blended with the coloured variety Shiraz, in 2:1 ratio, produced good quality wine.

Anthocyanins and proanthocyanidins from blueberry–blackberry fermented beverages inhibit markers of inflammation in macrophages and carbohydrate‐utilizing enzymes in vitro

Berries are an excellent source of dietary flavonoids which have several health benefits. We evaluated well-characterized anthocyanins (ANCs) and proanthocyanidins (PACs) from fermented blueberry-blackberry beverages. Wines were produced from highbush blueberries and blackberries grown in Illinois and blended to create ratios ranging from 100% blueberry to 100% blackberry. Total ANCs of the wine were strongly correlated to total phenolics (r = 0.99, p < 0.05) and to antioxidant capacity (r = 0.77, p < 0.05). ANC- and PAC-enriched fractions were purified from each wine blend and a phenolic profile was generated. ANCs increased with more blackberries from 1114 to 1550 mg cyanidin-3-O-glucoside (C3G) equivalents/L. Hydrolysable tannins were identified in the PAC-enriched fraction. Both ANC- and PAC-enriched fractions inhibited starch-degrading enzyme α-glucosidase and dipeptidyl peptidase-IV activity. Computational docking demonstrated that delphinidin-3-arabinoside effectively inactivated dipeptidyl peptidase-IV by binding with the lowest interaction energy (-3228 kcal/mol). ANC and PAC (100 μM C3G and epicatechin equivalents, respectively) from blueberry-blackberry blends reduced LPS-induced inflammatory response in mouse macrophages via the nuclear factor kappa B-mediated pathway. ANC- and PAC- (including hydrolysable tannins in blackberry) enriched fractions from blueberry and blackberry fermented beverages are beneficial sources of antioxidants, inhibitors of carbohydrate-utilizing enzymes, and potential inhibitors of inflammation.

Types of Grapes May Be Triggers

Intolerance reactions are not only associated generally with white, red, and rose wines but also with individual grape varieties. A case in point is the effect of the Merlot grape, which has become fashionable among wine drinkers in recent years. In patients with latent or manifest hypertension, a notable increase in blood pressure was observed after drinking Merlot, and this was accompanied by tachyarrhythmias. The reactions usually occur at night or in the early morning and are accompanied by symptoms resembling those of myocardial infarction. What is particularly striking is that even minute doses can trigger such reactions, and this also applies to blended wines consisting of a combination of several grapes, which often contain only 10–20% of Merlot. It is therefore recommended that these associations should be explained to patients with latent or manifest hypertension.

Berry and Citrus Phenolic Compounds Inhibit Dipeptidyl Peptidase IV: Implications in Diabetes Management

Beneficial health effects of fruits and vegetables in the diet have been attributed to their high flavonoid content. Dipeptidyl peptidase IV (DPP-IV) is a serine aminopeptidase that is a novel target for type 2 diabetes therapy due to its incretin hormone regulatory effects. In this study, well-characterized anthocyanins (ANC) isolated from berry wine blends and twenty-seven other phenolic compounds commonly present in citrus, berry, grape, and soybean, were individually investigated for their inhibitory effects on DPP-IV by using a luminescence assay and computational modeling. ANC from blueberry-blackberry wine blends strongly inhibited DPP-IV activity (IC50, 0.07 ± 0.02 to >300 μM). Of the twenty-seven phenolics tested, the most potent DPP-IV inhibitors were resveratrol (IC50, 0.6 ± 0.4 nM), luteolin (0.12 ± 0.01 μM), apigenin (0.14 ± 0.02 μM), and flavone (0.17 ± 0.01 μM), with IC50 values lower than diprotin A (4.21 ± 2.01 μM), a reference standard inhibitory compound. Analyses of computational modeling showed that resveratrol and flavone were competitive inhibitors which could dock directly into all three active sites of DPP-IV, while luteolin and apigenin docked in a noncompetitive manner. Hydrogen bonding was the main binding mode of all tested phenolic compounds with DPP-IV. These results indicate that flavonoids, particularly luteolin, apigenin, and flavone, and the stilbenoid resveratrol can act as naturally occurring DPP-IV inhibitors.

Ampelographic and oenological characterization of the ancient grapevine cv. Dobričić grown in the coastal region of Croatia

&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Aims&lt;/strong&gt;:A four-year study (2007 through 2010) was carried out to determine agronomic, biological, and oenological characteristics of Dobričić grapevines so as to evaluate this cultivar and protect it from extinction.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Methods and results&lt;/strong&gt;: 38 characteristics from the OIV descriptor list were used to describe young shoot, mature leaf, cluster, and berry morphology of Dobričić grapevines. The dimensions of an average leaf were constructed from measured leaf variables. A typical Dobričić genotype at nine microsatellite loci is presented. ELISA analysis revealed high virus incidence and all samples tested were GLRaV-3 positive. The profile of different classes of polyphenols in Dobričić wine was determined using HPLC and spectrophotometry. The concentrations of polyphenols in Dobričić wine, especially anthocyanins, hydroxycinnamic acids and stilbenes, were high compared to major red wines reported in the literature. Descriptive sensory analysis was carried out to determine the aroma attributes describing a Dobričić monovarietal wine.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Conclusion&lt;/strong&gt;: Knowledge of the biodiversity of the grapevine cultivars of Croatia is still scant. This study provides for the first time ampelographic and oenological information on Dobričić grapevines and demonstrates its high quality potential.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Significance and impact of the study&lt;/strong&gt;: The results of the ampelographic characterization would be helpful in the identification and selection of Dobričić for cultivation in certain vine-growing areas. The outstanding quality of Dobričić makes it very promising for wine blending (colour improvement) and plant breeding purposes.&lt;/p&gt;

Color-copigmentation study by tristimulus colorimetry (CIELAB) in red wines obtained from Tempranillo and Graciano varieties

A study of the changes of copigmentation phenomenon in wines elaborated from different varieties has been undertaken. Colorimetric measurement of Tempranillo (T) and Graciano (G) monovarietal wines, and two 80:20 blend wines: M, (grape blending T and G, co-maceration) and W (wine blending T and G, co-vinification) was performed by spectrophotometry. Significant differences (p<0.05) were found among the color of the wines. The Graciano cv. afforded somewhat darker and more colorful wines than the other wines. The color difference values, ΔE*ab suggested that co-vinification (W) led to wines being more similar to T than the co-maceration (M). The ΔE*ab[w−c] between untreated wines – whole wines, w – and the wines diluted to eliminate copigmentation – corrected wines, c – was 14.2 CIELAB units in the initial stages of winemaking and 6.7 in the final stages. M had a greater proportion of color due to copigmentation than the monovarietal wines. Evaluation of this parameter confirms the importance of copigmentation process into wine color during the early stages of the vinification. Also, through the full spectrum, quantitative data obtained allow a visual interpretation of the changes involved. In addition, with the aging in bottle, M wines had more stable color and more different color than W wines.