OENO IVAS 2019

Plant and Environment, Grape quality

Adapting wine production to climate change through the exploration of the diversity of Vitis vinifera cultivars

Major factors involved in wine quality and typicity are soil type, climatic conditions, plant material (rootstock and cultivar), vineyard management practices and winemaking conditions. All these factors interact and growers optimize the output in terms of yield and quality by adapting plant material and management practices to environmental factors (soil ...
Read more

Viticultural zoning of central chile based on bioclimatic indexes and the impact of climate warming

Climate is considered one of the main factors that determines the aptitude of a specific location for growing grapes and producing high quality wine, being in that sense one of the main elements defining the concept of terroir. Several bioclimatic indexes have been proposed that attempt to describe the climatic ...
Read more

Mitigating the effects of climate change on berry composition by canopy management

Primary and secondary metabolites are major components of grape composition and their balances define wine typicality. Global climate change is modifying vine physiology and especially the composition of grape berries at harvest, by decoupling phenolic and aromatic maturities (depending on secondary metabolites) from technical maturity (depending on primary metabolites). These ...
Read more

Aroma chemical profiles characterization of wines produced with moristel grapes harvested at different time points

The wine aroma is constituted by hundred of volatile chemical compounds that depend on many viticultural and oenological factors. One of the most important factors that will unequivocally affect the final wine pro-perties is the grape maturity level. Grape ripening is an extremely complex process, in which the metabolites and ...
Read more

Influence of pre-harvest elicitors treatment during ripening period on phenolic composition in Monastrell grapes

Phenolic compounds are very importants in crop plants, which is why there have been the subject of a large number of studies. There are three main reasons for optimising the level of phenolic compounds in crop plants: their physiological role in the plants, their technological significance for food processing, and ...
Read more

Coming of age: do old vines actually produce berries with higher enological potential than young vines? A case study on the Riesling cultivar

Consumers and the wine industry tend to agree on the ability of old vines to produce fruit that allows the production of wine of superior character. However, despite past and ongoing research, objective evidence of this point of view is still debated and studies on robust, specifically dedicated plots are ...
Read more

Nitrogen status of vines influences aged wines aromas. Examples of aged Champagne reserve wines and red Bordeaux wines

The sensory definition of the aging bouquet of red Bordeaux wines has been shown to be structured around seven main aromatic nuances: “undergrowth”, “spicy” “truffle”, “fresh red- and black-berry fruits”, “liquorice”, “mint”, and “toasted” (1). Some of these descriptors are also used to describe the aromatic notes of old Champagnes ...
Read more

Wine tannins: What place for grape seed?

Phenolic compounds are among the most important quality factors of wines. They contribute to the organoleptic characteristics of wine such as colour, astringency, and bitterness. Although tannins found in wine can come from microbial and oak sources, the main sources of polyphenols are skin and seed from grapes. Yet, the ...
Read more

Grape and wine microorganisms: diversity and adaptation

Fungal resident flora of a new winery: colonization, dynamics and potential persistence capacities

Through the years, extensive studies have been conducted on fungal biodiversity during the winemaking process: from the vineyard until aging. More recently, and as previously described for Saccharomyces cerevisiae, the persistence of winery resident flora (non-Saccharomyces yeasts) over time and its contribution to the alcoholic fermentation have been demonstrated. Also, ...
Read more

Genetic causes of SO2 consumption in Saccharomyces cerevisiae

SO2 is used during winemaking for its anti-oxidative and anti-microbial properties. A high SO2 concentration in the wine has negative impacts by hiding wine aromas and delaying malolactic fermentation. SO2 concentration is also a source of health concerns and is therefore legally regulated. During the alcoholic fermentation SO2 can be ...
Read more

Impact of non-Saccharomyces in malolactic fermentation of white and red winemaking

Nowadays the use of non-Saccharomyces as starters of alcoholic fermentation (AF) has increased because of the modulation of the organoleptic profile of wines. Additionally, these wines can undergo a malolactic fermentation (MLF) driven out by lactic acid bacteria, mainly Oenococcus oeni. Since MLF is usually performed after AF, MLF is ...
Read more

Mathematical modeling of fermentation kinetics: a tool to better understand interactions between Torulaspora delbrueckii and Saccharomyces cerevisiae in mixed cultures

Nowadays the use of Torulaspora delbrueckii is more and more common in winemaking. However, its behavior in presence of Saccharomyces cerevisiae is not always predictable. Indeed, the interactions existing between the two yeasts are still not well characterized and can lead to a bad control during their implementation in mixed ...
Read more

Nitrogen metabolism in Kluyveromyces marxianus and Saccharomyces cerevisiae: towards a better understanding of fermentation aroma production

During wine alcoholic fermentation, yeasts produce volatile aroma compounds from sugar and nitrogen metabolism. Some of the metabolic pathways leading to these compounds have been known for more than a century. Yet, the differences in compound yield and nature between species remain poorly understood. Using a two-pronged approach of isotopic ...
Read more

Œnological Practices and Process

Grape seed powder as an alternative to bentonite for wine fining

PR proteins can cause haze in wines, and the risk is to keep the wine unsold. Generally, in winemaking bentonite solves this problem by removing proteins, but it is not a renewable resource, has poor settling, which means difficulty in filtering after use and a considerable loss of wine, it ...
Read more

Foamability of bentonite treated wines: impact of new acacia gum fractions obtained by ionic exchange chromatography (IEC)

Foam is a key aspect of quality of sparkling wines. Bentonite is usually added to the wine to prevent protein haze, but reducing its foamability [1]. New skills are searching to avoid this undesirable event [2]. Acacia senegal gum (Asen) is an exudate from Acacia trees, which can be used ...
Read more

Optimizing the use of bentonite for better control of haze formation In white and rosé wines

In winemaking, the appearance of turbidity in white and wine is a serious visual defect, which lowers significantly its commercial value. A major cause of the formation of turbidity in wine is attributed to the presence of temperature-sensitive proteins. The proteins undergo slow conformational changes, leading to aggregation and flocculation ...
Read more

Simplifying the measurement of different forms of cu in wines and strategies for efficient removal

Copper (Cu) is known to substantially impact wine stability through oxidative, reductive or colloidal phenomena. Recent work has shown that Cu exists predominantly in a sulfide-bound form, which may act as a potential source of sulfidic off-odours in wine and hence contribute to reductive flavours. The quanti-fication of different forms ...
Read more

Bio-protection by one strain of M. Pulcherrima: microbiological and chemical impacts in red wines

Keywords: Wine bio-protection, Metschnikowia pulcherrima, Metabolomic, Volatile and phenolic compounds  In oenology, bio-protection consists in adding bacteria, yeasts or a mixture of microorganisms on grape must before fermentation in order to reduce the use of chemical compounds such as sulphites. More particularly, non-Saccharomyces yeasts are used as a total or partial ...
Read more

Analysis and composition of grapes, wines, wine spirits

A tool for catching mice in wine: development and application of a method for the detection of mousy off-flavour compounds in wine

Over the past two years, the AWRI has received 69 wine samples suspected of being affected by mousy off-flavour. The character has been mostly observed in white wines. Possible reasons for this could be the increased use of white winemaking techniques such as high grape solids ferments and extended lees ...
Read more

Trials with machine harvested sauvignon blanc: the importance of grape transport time and temperature

It is well known that free varietal thiols, in particular 3-mercaptohexanol (3MH) and 3-mercaptohexyl ace-tate (3MHA), are important constituents to the aroma of New Zealand Sauvignon blanc wines. This along with the popular practice of machine harvesting in New Zealand were the motivation for the following two pilot studies. Firstly, ...
Read more

Hplc-ms analysis of carotenoids as potential precursors for 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) in riesling grapes

In recent years, an undesirable premature “aged” character has been noticed in a growing number of young Riesling wines, associated with extreme weather conditions leading to increased radiation intensity and/ or sun exposure of grapes. One of the compounds responsible for rapid aging is 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN), a grape derived C13-norisoprenoid ...
Read more

The limonene-derived mint aroma compounds in red wines. Recent advances on analytical, chemical aspects and sensory aspects

In recent years, the ageing bouquet of red Bordeaux wines has been partially unveiled by a chemical and sensory point of view1–3. Minty and fresh notes were found to play a key role in the definition of this complex concept, moreover the freshness dimension in fine aged red wines plays ...
Read more

Evolution of the crown procyanidins during wine making and aging in bottle

Condensed tannins are widely distributed in plant‐derived foods and beverages like grape, red wine, nuts, tea, apples and chocolate in which they contribute to multiple sensorial properties such as flavor, color, and taste (astringency and bitterness). During the wine making process, condensed tannins are extracted from the skins and seeds ...
Read more

Chemical and Biochemical reactions, including grape and wines microorganisms impact

What is the fate of oxygen consumed by red wine? Main processes and reaction products

Oxygen consumed by wine is used to oxidize sulfur dioxide and ethanol to form acetaldehyde wine oxygen consumption rate (OCR) was negatively correlated with the initial acetaldehyde level. Experiences carried out at 25 ºC with red wines have demonstrated that after consuming a large amount of O2, some young wines did not form ...
Read more

Impact of glutathione-rich inactivated yeast on wine chemical diversity

Glutathione-rich inactivated dry yeasts (GSH-IDY) are claimed to accumulate intracellularly and then release glutathione in the must. Glutathione is beneficial to the wine quality, but scientists also highlighted that GSH-IDYs have a greater effect than only increase the pool of this antioxidant in the wine. This work unveils the extent ...
Read more

Are dicysteinyl polysulfanes responsible for post-bottling release of hydrogen sulfide?

Hydrogen sulfide (H2S) has a significant impact on wine aroma attributes and wine quality when present at concentrations above its aroma threshold of 1.1 to 1.6 μg/L. Therefore, the management of H2S concentrations in wines, whether from fermentation or “other” origins, is an important consideration for winemakers. The main techniques ...
Read more

NMR approach for monitoring the photo-degradation of riboflavin and methionine

The light exposure of white wine is responsible for several reactions leading to changes on colour, flavours and, consequently, affecting the sensory profile. These reactions can take place when the white wine is bottled in clear glass and their mechanisms are dependent on both light exposure and chemical composition of ...
Read more

Study of yeast biocatalytic activity on grape aroma compounds

Many volatile compounds of different chemical/biochemical origin contribute to wine aroma. Certain key ‘varietal’ aroma compounds such as methoxypyrazines are formed in the grape and appear to be only scarcely influenced by fermentation. Conversely, other grape-derived compounds undergo important transformation during fermentation, so that grape varietal volatile pattern is substantially ...
Read more

Analytical developments from grape to wine, spirits omics, chemometrics approaches

Integrated multiblock data analysis for improved understanding of grape maturity and vineyard site contributions to wine composition and sensory domains

Much research has sought to define the complex contribution of terroir (varieties x site x cultural practices) on wine composition. This investigation applied recent advances in chemometrics to determine relative contributions of vine growth, berry maturity and site mesoclimate to wine composition and sensory profiles of Shiraz and Cabernet Sauvignon ...
Read more

Can wine composition predict quality? A metabolomics approach to assessing Pinot noir wine quality as rated by experts

The perception of wine quality is determined by the assessment of multiple sensory stimuli, including aroma, taste, mouthfeel and visual aspects. With so many different parameters contributing to the overall perception of wine quality, it is important to consider the contribution of all metabolites in a wine when attempting to ...
Read more

D-wines: use of LC-MS metabolomic space to discriminate italian mono-varietal red wines

Studying wine metabolome through multiple targeted methods is complicated and limitative; since grapes, yeasts, bacteria, oxygen, enological techniques and wine aging collaborate to deliver one of the richest metabolomic fingerprint. Therefore, untargeted metabolomics, that developed and evolved as a consequence of the need to obtain a comprehensive characterization of the ...
Read more

LC-MS based metabolomics and target analysis to study the chemical evolution of wines stored under different redox conditions

Oxygen is a key player in oenology, since its effects can be a blessing, benefiting wine quality, or a curse causing irreversible damage. Therefore, many modern winemaking choices tend to favor reduction, even if the severe lack of oxygen can be responsible for a loss in quality due to the ...
Read more

Fully automated non-targeted GC-MS data analysis

Non-targeted analysis is applied in many different domains of analytical chemistry such as metabolomics, environmental and food analysis. In contrast to targeted analysis, non-targeted approaches take information of known and unknown compounds into account, are inherently more comprehensive and give a more holistic representation of the sample composition.  Besides chromatographic ...
Read more

Sensory properties, psychophysics, experimental economy, connexions with neurosciences

Comparing the effects of vision, smell and taste in red wine quality judgments by experts: sensory cues, mental imagery and verbal representations as drivers of consensus in the multisensory space

In this study, we evaluated the contributions of vision, smell and taste to red wine quality judgments by expert wine tasters. Whereas previous studies specified the modulating effects of gustatory traits [1], culture and expertise [2, 3], our objective was to gain a better understanding of the perceptual mechanisms, with ...
Read more

Does wine expertise influence semantic categorization of wine odors?

Aromatic characterization is a key issue to enhance wines knowledge. While several studies argue the importance of wine expertise in the ability of performing odor-related sensory tasks, there is still little attention paid to the influence of expertise on the semantic representation of wine odors. Theis study aims at exploring ...
Read more

Exploring multisensory interactions through the study of astringency diversity of mono-varietal Italian red wines

According to the OIV Focus 2017 estimating the vine varieties distribution in the world, Italy is the richest grape producing country in terms of varieties. This rich biodiversity translates into a wide sensory diversity of the wines that was never systematically investigated. The D-Wines (Diversity of Italian Wines) project, is ...
Read more

Red wine astringency: evolution of tribological parameters during different harvest dates

Astringency is a specific oral sensation dominated by dryness and puckering feeling and is one of the leading quality factors for red wines, as well as some fruit products. Based on this sensory parameter, are made relevant decisions in wine production including the moment of grape harvest (phenolic ripeness), the ...
Read more

Sensory evaluation of grape berries: predictive power for sensory properties of Sauvignon blanc, Riesling and Pinot noir wines

Sensory analysis of grape berries is a common tool to evaluate the degree of grape maturation and to make sound picking decisions. However, most of it is based on anecdotal knowledge and scientific studies relating berry and wine properties are rather limited [1].  Ten grapes of each variety (Sauvignon Blanc, ...
Read more

Analytical tools using electromagnetic spectroscopy techniques (IR, fluorescence, Raman)

Determination of titratable acidity, sugar and organic acid content in red and white wine grape cultivars during ripening by VIS–NIR hy¬perspectral imaging

Grape harvest time is one of the most fundamental aspects that affect grape quality and thus wine quality. Many factors influence the decision of harvest; among them technological and phenolic maturity of grape. Technological ripeness is mainly related to sugar concentration, titratable acidity and pH. Conventional methods for chemical analysis ...
Read more

Use of Fourier Transform Infrared Spectroscopy (FTIR) to rapidly verify the botanical authenticity of gum arabic

Gum arabic is composed of a polysaccharide rich in galactose and arabinose along with a small protein fraction [1, 2], which gives its stabilizing power with respect to the coloring substances or tartaric precipitation of bottled wine. It is a gummy exudation from Acacia trees; the products used in enology ...
Read more

Monitoring small-scale alcoholic fermentations using a portable FTIR-ATR spectrometer and multivariate analysis

Although some wine production processes still rely on post-production evaluation and off-site laboratory analysis, the new winemaking industry is aware of a need for a better knowledge of the process to improve the properties of the final product. Thus, more and more wineries are interested in incorporating quality-by-design (QbD) strategies ...
Read more

Development of FTIR partial least squares models for polyphenol quantification in red wine during fermentation

Polyphenolic compounds are considered to have a major impact on the quality of red wines. Sensory impact, such as astringency and bitterness, stems directly from tannin composition. Thenceforth, quick analytical measurement of phenolic compounds appears to be a real challenge for winemaking monitoring and process control.  Many methods were developed ...
Read more

Multivariate characterization of Italian monovarietal red wines using FTIR spectroscopy

The assessment of wine authenticity is of great importance for consumers, producers and regulatory agencies to guarantee the geographical origin of wines and grape variety as well. Since mid-infrared (MIR) spectroscopy with chemometrics represent a suitable tool to ascertain the wine composition, including features associated with the polyphenolic compounds, the ...
Read more

OENO-IVAS 2019: View all

Copy link
Powered by Social Snap