Search results for " wine."
showing 10 items of 331 documents
Screening of Hanseniaspora Strains for the Production of Enzymes with Potential Interest for Winemaking
2015
Some non-Saccharomyces yeasts, including Hanseniaspora, participate in the first stages of wine fermentation. Besides their importance in the wine production process some of these yeasts have been described to be potential producers of hydrolytic enzymes to industrial level. In this work, we pretend to evaluate the technological abilities of the Hanseniaspora strains deposited in the Spanish Type Culture Collection (CECT). First of all, we considered verification of the correct identification of the strains using several miniaturized biochemical systems and molecular techniques (PCR, RFLP and sequencing of the ribosomal D1/D2 region). The results allowed us to verify the correct adscription…
Stress response and expression patterns in wine fermentations of yeast genes induced at the diauxic shift
2000
During wine fermentation yeasts quickly reach a stationary phase, where cells are metabolically active by consuming sugars present in grape must. It is, consequently, of great interest at this stage to identify suitable gene promoters that may be used to induce the expression of genes with enological applications. With this aim, we have studied a group of genes showing an induction peak at the diauxic shift, and possessing stress response elements (STRE) at their promoters. We have determined their induction levels under individualized stress conditions, such as carbon source starvation or high salt concentrations. In all the cases studied, the activation and/or basal transcription are depe…
A comparative study of the wine fermentation performance of Saccharomyces paradoxus under different nitrogen concentrations and glucose/fructose rati…
2010
8 pages, 1 figure, 4 tables.-- Online version published: May 2009.-- The definitive version is available at www3.interscience.wiley.com
Selection and molecular characterization of wine yeasts isolated from the ‘El Penedès’ area (Spain)
2000
Abstract A study of the microbiota present during the wine fermentation of five grape varieties from the ‘El Penedes’ area (Spain) was carried out to select autochthonous yeast strains for industrial wine production. In this study we identified members of the genera Candida, Dekkera, Hanseniaspora, Kluyveromyces, Torulaspora, Zygosaccharomyces and Saccharomyces in wine fermentation microbiota. Strains of Saccharomyces cerevisiae, as responsible agents of the alcoholic fermentation, were considered for a selection protocol. In this work we applied different enological criteria for selection, but previously we have characterized and differentiated Saccharomyces isolates by molecular methods t…
Amino acids and volatile compounds in wines from Cabernet Sauvignon and Tempranillo varieties subjected to malolactic fermentation in barrels
2012
The aim of the present paper is to compare the behaviour of industrial lactic bacteria and indigenous bacteria of the cellar when malolactic fermentation was carried out in barrels. The effects of these bacteria on the concentration of metabolised amino acids during malolactic fermentation and on the composition of volatile compounds both before and after malolactic fermentation are studied. The experiment was performed with wines of the Tempranillo and Cabernet Sauvignon varieties. An analysis has been made of the easily extractable volatile compounds of the wood and the compounds from the grapes, and the action of the yeasts during the alcoholic fermentation. Acetoin and diacetyl decreas…
Aroma compounds in wine as influenced by apiculate yeasts
1996
Aroma compounds of wines resulting from fermentation of sterile grape musts from Monastrell variety inoculated with pure and mixed cultures of apiculate and Saccharomyces yeasts, were isolated and analyzed by gas chromatography with flame ionization and mass spectrometry. Samples fermented with mixed cultures produced a higher concentration of selected compounds and higher total amounts of alcohols and acids, in contrast with wines produced with pure cultures of Saccharomyces spp. Apiculate yeasts are important in the chemical composition and quality of wine.
Different Behaviour of Plasma Antioxidant Status after Red Wine Consumption in Subjects of the Same Sex: A Preliminary Report
2012
<p>Several studies report that the plasma antioxidant capacity (PAC) increases after a single ingestion of red wine. However, data on the different behaviour of PAC after food intake in subjects of the same sex are still lacking. On the basis of these observations some investigations were undertaken in order to evaluate the effects of red wine intake on PAC in a homogeneous groups of healthy female volunteers (n=18). Additionally, the possible correlation between increase of PAC values and increase in uric acid levels was also assessed. PAC and uric acid concentrations were determined before wine intake and 50, 120 and 240 minutes thereafter. The results obtained following these studi…
Intraspecific biodiversity and 'spoilage potential' of Brettanomyces bruxellensis in Apulian wines
2015
Abstract The yeast Brettanomyces bruxellensis, generally considered the main oenological spoilage microbe, is able to survive during the winemaking process and it confers off-odors to wine, in reason of its ability to produce considerable amounts of volatile phenols. Forty-eight isolates of B. bruxellensis, obtained from several wines collected in Apulia (Southern Italy), were genetically characterized using an integrated approach, including a strain biodiversity analysis by Sau-PCR. Furthermore, the production of volatile phenols was assessed in wine and in synthetic medium, confirming the oenological spoilage potential of the analysed strains. Our findings indicate a remarkable genetic va…
Adaptive evolution of wine yeast.
2003
Abstract Alcoholic fermentation is one of the main phases in wine production. It is usually conducted by yeasts belonging to the species Saccharomyces cerevisiae. Industrial S. cerevisiae strains are highly specialized organisms, which have evolved to utilize to their full potential the different environments or ecological niches. So, during the alcoholic fermentation, the yeast has been adapted to different kinds of stress conditions; this adaptation is call “domestication”. In this review, we describe the different mechanisms involved in the adaptive evolution of wine yeast strains.
Isolating Wine Yeasts that are Specific to the Apold Region and Identifying them through RFLP Genetic Methods
2015
The present study aims at isolating, identifying and selecting autochthonous wine yeast strains with a view to establish a crop bank specific to the Apold area. 569 wine yeast strains were isolated during the alcoholic fermentation of must from the Apold area, 458 were identified through cultural methods and with the help of the API 20 C AUX test (Biomeriux, France). Six yeast strains (A87, A169, A296, A314, A132 and A413) were genetically identified through the PCR-ITS RFLP method of the 5.8S-ITS segment; the resulting four strains were Saccharomyces cerevisiae - A87, A169, A296, A314 - and two Saccharomyces bayanus strains - A132 și A413. The strains we identified constitute a base for t…