SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Bordeaux

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New Zealand Sauvignon blanc (SB) wines are characterised by a distinctive combination of tropical-fruity and green-herbaceous aromatic compounds. The influence of sunlight exposure of grape clusters on juice and wine composition was investigated, with the aim of manipulating aromatic compounds in SB wine. In the absence of basal leaf removal SB clusters naturally exposed to sunlight were riper than shaded clusters, evidenced by higher total soluble solids (TSS) and proline, and lower malic acid, 3-isobutyl-2-methoxypyrazine (IBMP) and arginine. Volatile thiols in wines did not differ between shaded and exposed clusters. At equivalent TSS, cluster exposure had little or no effect on malic acid concentration. Conversely, wine from shaded clusters had almost double the IBMP concentration of wine from exposed clusters at equivalent TSS. The effects on SB juice and wine composition of natural variations in cluster microclimate are not comparable with the effects of cluster exposure created through leaf removal.

Concepts: Vitis vinifera, Wine, Fermentation, Cabernet Sauvignon, Sauvignon blanc, Chardonnay, Bordeaux, Chilean wine

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In the wine industry, fining agents are commonly used with many choices now commercially available. Here the influence of pre-fermentation fining on wine aroma chemistry has been explored. Free run and press fraction Sauvignon blanc juices from two vineyards were fined using gelatin, activated carbon, polyvinylpolypyrrolidone (PVPP) and a combination agent which included bentonite, PVPP and isinglass. Over thirty aroma compounds were quantified in the experimental wines. Results showed that activated carbon fining led to a significant (p<0.05) concentration decrease of hexan-1-ol and linalool in the experimental wines when compared to a control, consistent across all vineyard and fraction combinations. Other aroma compounds were also influenced by fining agent, even if vineyards and press fractions played a crucial role. This study confirmed that fining agents used pre-fermentation can influence wine aroma profiles and therefore needs specific tailoring addressing style and origin of grape.

Concepts: Brewing, Oenology, Fermentation, Oak, Sauvignon blanc, Bordeaux, Isinglass, Finings

11

This study investigated how information, typically presented on wine back-labels or wine company websites, influences consumers' expected liking, informed liking, wine-evoked emotions and willingness to pay for Australian white wines. Regular white wine consumers (n=126) evaluated the same set of three commercially available white wines (mono-varietal Chardonnay, Riesling, Sauvignon Blanc) under three information levels. Session 1, blind tasting (no information provided) and Session 2, informed tasting (held at least 1week later) with both basic (sensory description of the wines) and elaborate (sensory plus high wine quality and favourable winery information) descriptions followed by liking, wine-evoked emotions (measured with the Australian Wine Evoked Emotions Lexicon (AWEEL)) and willingness to pay evaluations. Before tasting the wine in session 2, consumers also rated expected liking. Results showed that information level had a significant effect on all investigated variables. The elaborate information level evoked higher expectations before tasting the wines, plus resulted in higher liking ratings, elicitation of more intense positive (e.g. contented, happy and warm-hearted) and less intense negative emotions (e.g. embarrassed and unfulfilled), and a substantial increase in willingness to pay after tasting the wines compared to the blind condition, with the basic condition ranging in-between. These results were consistent across the three wine samples. Furthermore, if the liking rating after tasting the wines matched the expected liking or exceeded the expectations by 1 point on a 9-point hedonic scale, participants felt the most intense positive emotions and the least intense negative emotions. Whereas, if the expectations were not met or the actual liking exceeded the expectations by >2 points, participants felt less intense positive and more intense negative emotions. This highlights not only the importance of well written and accurate wine descriptions, but also that information can influence consumers' wine drinking experience and behaviour.

Concepts: Wine, Fermentation, Cabernet Sauvignon, Chardonnay, South African wine, Bordeaux, Chilean wine, German wine

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The structural characterization of the polysaccharides and in vitro anti-inflammatory properties of Cabernet Franc (WCF), Cabernet Sauvignon (WCS) and Sauvignon Blanc (WSB) wines were studied for the first time in this work. The polysaccharides of wines gave rise to three fractions of polysaccharides, namely (WCF) 0.16%, (WCS) 0.05% and (WSB) 0.02%; the highest one was chosen for isolation of polysaccharides (WCF). It was identified the presence of mannan, formed by a sequence of α-d-Manp (1 → 6)-linked and side chains O-2 substituted for α-d-mannan (1 → 2)-linked; type II arabinogalactan, formed by (1 → 3)-linked β-d-Galp main chain, substituted at O-6 by (1 → 6)-linked β-d-Galp side chains, and nonreducing end-units of arabinose 3-O-substituted; type I rhamnogalacturonan formed by repeating (1 → 4)-α-d-GalpA-(1 → 2)-α-L-Rhap groups; and traces of type II rhamnogalacturonan. The polysaccharide mixture and isolated fractions inhibited the production of inflammatory cytokines (TNF-α and IL-1β) and mediator (NO) in RAW 264.7 cells stimulated with LPS.

Concepts: Cabernet Sauvignon, Merlot, Bordeaux wine, Grape varieties, Sauvignon blanc, Bordeaux, Chilean wine, California wine

0

A novel analytical method was developed for quantitative determination of eight limonene-derived monoterpenes responsible for the mint aroma in red wine. As these aromatic compounds are present at trace levels, a new dual extraction approach was proposed, combining solid-phase extraction (SPE) and stir bar sorptive extraction (SBSE), followed by gas chromatography-mass spectrometry analysis. The various parameters affecting the efficiency of extracting the analytes from wine samples in both the SPE and SBSE steps were first investigated, to determine the best compromise for the simultaneous analysis of the compounds studied. Following preliminary optimization of the dilution factor, phase ratio, and methanol content in the SBSE sample, cartridge sorbent mass, type of solvent, elution volume, and wine sample volume in the pre-concentration SPE step were studied. Highest response values were obtained when a 90 mL wine sample was extracted on a 500 mg SPE C18 cartridge and eluted with 1.5 mL methanol. The wine extract was then diluted in 10 mL water to obtain a final methanol content of 15% before the SBSE step. Good linearity, repeatability, reproducibility, accuracy and the required low detection and quantification limits were obtained under the conditions described, making this SPE-SBSE combination a suitable, powerful tool for routine analysis of the selected limonene-derived mint aroma compounds in large series of wine samples. Finally, the validated method was applied to 15 commercial red Bordeaux wines, aged from 3 to 23 years. Most of the compounds studied, present within the ng.L-1range, were easily quantified for the first time in wine.

Concepts: Analytical chemistry, Wine, Fermentation, Cabernet Sauvignon, Merlot, Bordeaux wine, Bordeaux

0

The copper contents in vineyard soil, grape must and wine and the relationship among them in the Huaizhuo Basin Region, China, were investigated. The results showed that the copper pollution status in vineyard soils, grapes and wines in the investigated area in China is under control, with only 4 surface soil (0-20cm) samples over maximum residue limits (MRL) and no grape or wine samples over MRL. Different vineyards, grape varieties, vine ages, and training systems all significantly influenced the copper contents in the vineyard soils, grape and wines. Additionally, the copper levels in the vineyard soils, grapes and wines all had some correlation. In wine samples, the copper contents ranged from 0.52 to 663μg/L, which is only approximately one percent the level found in grapes and one ten-thousandth that found in soils. Of the wine samples, red wines showed a significantly higher copper content than white wines, while in the red/white grape and soil samples, no significant differences were observed.

Concepts: Yeast, Vitis vinifera, Wine, Grape, Viticulture, Vitis riparia, Cabernet Sauvignon, Bordeaux

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Weather conditions throughout the year have a greater influence than other factors (such as soil and cultivars) on grapevine development and berry composition. Temperature affects gene expression and enzymatic activity of primary and secondary metabolism which determine grape ripening and wine characteristics. In the context of the climate change, temperatures will probably rise between 0.3°C and 1.7°C over the next 20 years. They are already rising and the physiology of grapevines is already changing. These modifications exert a profound shift in primary (sugar and organic acid balance) and secondary (phenolic and aromatic compounds) berry metabolisms and the resulting composition of wine. For example, some Bordeaux wines have a tendency toward reduced freshness and a modification of their ruby color. In this context it is necessary to understand the impact of higher temperatures on grape development, harvest procedures, and wine composition in order to preserve the typicity of the wines and to adapt winemaking processes.

Concepts: Metabolism, Vitis vinifera, Wine, Grape, Cabernet Sauvignon, Merlot, Bordeaux wine, Bordeaux

0

This study focuses on the fate of pharmaceuticals discharged into an estuarine environment, particularly into the Turbidity Maximum Zone (TMZ). Batch experiments were set up to investigate the factors regulating the degradation of 53 selected pharmaceuticals. Treated effluents from Bordeaux city (France) were mixed with water from the estuarine Garonne River during 4weeks under 6 characterized conditions in order to assess the influence of suspended particulates, sterilization, untreated wastewater input and dilution on the degradation kinetics. Of the 53 pharmaceuticals monitored, 43 were quantified at the initial time. Only 7 exhibited a persistent behavior (e.g. carbamazepine, meprobamate) while biotic degradation was shown to be the main attenuation process for 38 molecules (e.g. abacavir, ibuprofen highly degradable). Degradation was significantly enhanced by increasing concentrations of suspended solids. A persistence index based on the half-lives of the compounds has been calculated for each of the 43 pharmaceuticals to provide a practical estimate of their relative stability. The stability of pharmaceuticals in estuarine environments is likely to be highly variable and attenuated primarily by changes in suspended solid concentration.

Concepts: Water, Water pollution, France, Total suspended solids, Bottom trawling, Bordeaux, Gironde, Garonne

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The typical fruity aroma of red Bordeaux wines depends on the grape variety but also on microbiological processes, such as alcoholic and malolactic fermentations. These transformations involve respectively the yeast Saccharomyces cerevisiae and the lactic acid bacteria Oenococcus oeni. Both species play a central role in red winemaking but their quantitative and qualitative contribution to the revelation of the organoleptic qualities of wine has not yet been fully described. The aim of this study was to elucidate the influence of sequential inoculation of different yeast and bacteria strains on the aromatic profile of red Bordeaux wine.

Concepts: Bacteria, Yeast, Saccharomyces cerevisiae, Wine, Fermentation, Cabernet Sauvignon, Bordeaux wine, Bordeaux

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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.

Concepts: Wine, Cabernet Sauvignon, Merlot, Bordeaux wine, Bordeaux, Graves