Search results for " wine."

Molecular Identification of Lactic Acid Bacteria Occurring in Must and Wine

2016

A specifically amplified polymorphic DNA-polymerase chain reaction (SAPD-PCR), a molecular fingerprinting method based on the amplification of specific gene sequences, was applied in order to allow a rapid identification of lactic acid bacteria (LAB) occurring in must and wine. The applicability of this method was confirmed with isolated strains from different wine samples from the German wine growing region Palatinate. In addition, the formation of biogenic amines by the isolated strains was studied. More than half of the bacterial isolates from 50 red and white wine samples were able to produce biogenic amines. General health concerns related to biogenic amines in must and wine underline …

Viable But Not Culturable (VBNC) state of Brettanomyces bruxellensis in wine: New insights on molecular basis of VBNC behaviour using a transcriptomi…

2016

International audience; The spoilage potential of Brettanomyces bruxellensis in wine is strongly connected with the aptitude of this yeast to enter in a Viable But Non Culturable (VBNC) state when exposed to the harsh wine conditions. In this work, we characterized the VBNC behaviour of seven strains of B. bruxellensis representing a regional intraspecific biodiversity, reporting conclusive evidence for the assessment of VBNC as a strain-dependent character. The VBNC behaviour was monitored by fluorescein diacetate staining/flow cytometry for eleven days after addition of 0.4, 0.6, 0.8, 1 and 1.2 mg/L of molecular SO2 (entrance in the VBNC state) and after SO2 removal (exit from the VBNC st…

2018

Chardonnay wines from Burgundy, obtained from musts with three levels of clarification (Low, Medium and High) during two consecutive vintages (2009 and 2010) and for two kinds of closures (screw caps and synthetic coextruded closures) were analyzed chemically and sensorially. Three bottles per turbidity level were opened in 2015 in order to assess the intensity of the reductive and/or oxidative aromas (REDOX sensory scores) by a trained sensory panel. The chemical analyses consisted in polyphenols and colloids quantification, followed by a proteomic characterization. For the two vintages, the REDOX sensory scores appeared to be driven both by the type of closure and to a lesser extent by th…

Polyphenol-rich and alcoholic beverages and metabolic status in adults living in Sicily, Southern Italy

2021

Polyphenol-rich beverage consumption is not univocally accepted as a risk modulator for cardio-metabolic risk factors, despite mechanistic and epidemiological evidence suggesting otherwise. The aim of this study was to assess whether an association between polyphenol-rich beverage consumption and metabolic status could be observed in a Mediterranean cohort with relatively low intake of tea, coffee, red and white wine, beer, and fresh citrus juice. Demographic and dietary characteristics of 2044 adults living in southern Italy were analyzed. Multivariate logistic regression analyses were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) of the association between polyphe…

Inoculation of Torulaspora delbrueckii as a bio-protection agent in winemaking

2018

International audience; 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-Saccharvinyces yeasts are used as a total or partial alternative to sulphites. However, scientific data capable of proving the effectiveness of adding these yeasts on grape must is lacking. This study reports the analysis of antimicrobial and antioxidant effects of one non-Saccharamyces yeast, Torulaspora delbruecicii, inoculated at the beginning of the white winemaldng process in two Burgundian wineries as an alternative to sulphiting. The implantati…

Colour as a driver of Pinot noir wine quality judgments: An investigation involving French and New Zealand wine professionals

2016

Despite anecdotal reports suggesting an influence of perceived wine colour on wine professionals’ judgments of wine intrinsic quality, there is a lack of empirical evidence on the phenomenon. The major aim of the present study was to investigate the importance of perceived colour as a driver of chemosensory judgments of Pinot noir wines including sensory evaluations of quality and typicality. Twenty-three French and 23 New Zealand (NZ) wine professionals judged Pinot noir wines from France and NZ on a range of attributes including perceived colour (hue, intensity, and brightness), varietal characteristics, and overall wine quality. The wines were evaluated in both standard clear glassware w…

Quality and volatile compounds in red wine at different degrees of dealcoholization by membrane process

2019

This study investigated the effect of different degrees of dealcoholization on volatile compounds, phenols and sensory characteristics of red wine (cv. Montepulciano d’Abruzzo). The wine with an initial alcohol content of 13.2% v/v was partially dealcoholized by membrane process with a decrease of alcohol degree as follows: − 4.9; − 6.3; − 7.8, − 9.2 and − 10.5% v/v. Osmotic distillation has proved effective in preserving a satisfactory odorous profile, as samples with an alcohol residue of 8.3% v/v (− 4.9%) and 6.9% v/v (− 6.3%) showed good esters retention: more than 84% and 82%, respectively. Similarly, colour and taste, evaluated by flavonoids and phenolic compounds, remained almost unc…

Impact of ethanol on the perception of wine odorant mixtures

2007

International audience; Several studies have focused on perceptual interactions in binary odor mixtures, but few on more complex mixtures. The aroma of wine is an example of a complex odor mixture. Our aim was to assess the impact of ethanol on the perception of mixtures of Woody (whiskey lactone) and Fruity (isoamyl acetate) odorants commonly found, physico-chemically and perceptually, in wine. Physico-chemically, reduced whiskey lactone volatility was observed in hydro-alcoholic solutions. Perceptually, a synergy effect by the Woody on the Fruity odor was observed in aqueous solutions, which disappeared with the addition of ethanol. Conversely, the Woody odor was masked in both aqueous an…

2017

Nitrogen sources in the must are important for yeast metabolism, growth, and performance, and wine volatile compounds profile. Yeast assimilable nitrogen (YAN) deficiencies in grape must are one of the main causes of stuck and sluggish fermentation. The nitrogen requirement of Saccharomyces cerevisiae metabolism has been described in detail. However, the YAN preferences of non-Saccharomyces yeasts remain unknown despite their increasingly widespread use in winemaking. Furthermore, the impact of nitrogen consumption by non-Saccharomyces yeasts on YAN availability, alcoholic performance and volatile compounds production by S. cerevisiae in sequential fermentation has been little studied. With…

Construction of a genetically modified wine yeast strain expressing the Aspergillus aculeatus rhaA gene, encoding an -L-Rhamnosidase of enological in…

2003

Monoterpenes such as geraniol, linalool, and -terpineol present in grapes determine the varietal flavor properties of young quality wines made from Muscat varieties (for reviews, see references 19 and 21). Geraniol and linalool are considered to be the most important of the monoterpene alcohols, as they are present in greater concentrations and have lower flavor thresholds than other major wine monoterpenes. In particular, linalool is thought to be responsible for the grapelike aroma of wines produced from the Muscat variety. A large proportion of