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Varietal thiols in white wines from portuguese grape varieties

Effect of malolactic fermentation on the volatile profile of wines

Pesquisa de compostos voláteis de enxofre varietais em vinhos brancos elementar...

Volatile compounds contribution of Hanseniaspora guilliermondii and Hanseniaspo...

This work aims to investigate the contribution of a selected non-Saccharomyces yeast species, Hanseniaspora guilliermondii, to higher alcohols, esters, fatty acids and heavy sulphur compounds composition of red wine. Red grape must vinifications of 100 l were performed and an inoculated fermentation with H. guilliermondii was compared to a spontaneous fermentation. The presence of apiculate yeasts was observed ...

Políticas de Alimentação e nutrição: Brasil e Portugal

Como Política Nutricional entende-se um conjunto de medidas intersectoriais que visam garantir o acesso universal aos alimentos, considerando o estado nutricional e a promoção da saúde da população. Com contextos demográficos, epidemiológicos e nutricionais diferentes, será de espera que Portugal e Brasil apresentem acções distintas no âmbito destas políticas. No Brasil, os temas alimentação e nutrição desde 19...

Heavy sulphur compounds, higher alcohols and esters production profile of Hanse...

Hanseniaspora guilliermondii and Hanseniaspora uvarum were tested in grape must fermentations as pure and mixed starter cultures with Saccharomyces cerevisiae. In pure cultures, the specific growth rates found were 0.29 h⁻¹ for H. uvarum, 0.23 h⁻¹ for H. guilliermondii and 0.18 h⁻¹ for S. cerevisiae. No significant differences were observed between these values and those obtained in mixed cultures. Results pres...

Production of 1,3-Propanediol by Clostridium butyricum VPI 3266 in continuous c...

The effects of dilution rate and substrate feed concentration on continuous glycerol fermentation by Clostridium butyricum VPI 3266, a natural 1,3-propanediol producer, were evaluated in this work. A high and constant 1,3-propanediol yield (around 0.65 mol/mol), close to the theoretical value, was obtained irrespective of substrate feed concentration or dilution rate. Improvement of 1,3-propanediol volumetric p...

Method for analysis of heavy sulphur compounds using gas chromatography with fl...

A method for analysis of heavy sulphur compounds in wines, based on gas chromatography (GC) with flame photometric detection, is reported. Wine samples preparation includes a dichloromethane liquid–liquid extraction followed by concentration under a nitrogen atmosphere. The extracted fraction was also analysed by GC–mass spectrometry. The method enables high recovery of sulphur compounds in wine and satisfies t...

Production of 1,3-propanediol by Clostridium butyricum VPI 3266 using a synthet...

Growth inhibition of Clostridium butyricum VPI 3266 by raw glycerol, obtained from the biodiesel production process, was evaluated. C. butyricum presents the same tolerance to raw and to commercial glycerol, when both are of similar grade, i.e. above 87% (w/v). A 39% increase of growth inhibition was observed in the presence of 100 g l 1 of a lower grade raw glycerol (65% w/v). Furthermore, 1,3-propanediol prod...

A GAC biofilm reactor for the continuous degradation of 4-chlorophenol: treatme...

Using a continuous enrichment technique, a bacterial consortium capable of degrading 4-chlorophenol (4-CP) was obtained from the rhizosphere of Phragmites australis. A granular activated carbon (GAC) biofilm reactor was established using this consortium, and the degradation of 4-CP was investigated under continuous flow operation using a feed of 20-50 mg l-1 with a hydraulic residence time of 17 min over a 6-mo...