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Fedrizzi B.,University of Padua | Zapparoli G.,University of Verona | Finato F.,Unione Italiana Vini Societa Cooperativa | Tosi E.,Centro per la Sperimentazione in Vitivinicoltura | And 3 more authors.
Journal of Agricultural and Food Chemistry | Year: 2011

From harvest until wine arrives to the consumer, oxygen plays a crucial role in the definition of the final aroma. In the present research, the effect of the model oxidative aging on a dry red Botrytis wine, such as Italian Amarone, was considered. Amarone wine was submitted to model oxidative aging and then analyzed with two different approaches (SPE-GC-MS and HS-SPME/GC-MS). The same sampling plan was adopted to study the model aging of the same Amarone wine in anaerobic conditions. The HS-SPME/GC-MS method was applied to investigate for the first time the effect of the oxidative aging on a vast number of fermentative sulfur compounds. This research highlighted peculiar evolutions for several volatile compounds. In particular, benzaldehyde showed a sensitive increment during the oxidative aging, with a rate much higher than that reported for non-Botrytis red wines. On the other hand, several sulfides (dimethyl sulfide, 3-(methylthio)-1-propanol, etc.) disappeared after just 15 days of oxidative aging. A wine oxidation marker such as 3-(methylthio)-propanal was not found in any of the oxidized wines; conversely methionol-S-oxide was tentatively identified. This evidence has not been mentioned in the literature. A possible involvement of grape withering process and Botrytis in these mechanisms was supposed: a dry red wine, produced from the same but without any grape withering process and Botrytis infection (e.g., Bardolino wine), was submitted to oxidative aging and analysis. This red wine showed an evolution similar to those reported in the literature for dry red wines but significantly different from the Amarone wine. © 2011 American Chemical Society.

Azzolini M.,University of Verona | Tosi E.,Centro per la Sperimentazione in Vitivinicoltura | Lorenzini M.,University of Verona | Finato F.,Unione Italiana Vini | Zapparoli G.,University of Verona
World Journal of Microbiology and Biotechnology | Year: 2014

Although the positive role of non-Saccharomyces yeasts on the overall quality of wine is encouraging research into their oenological potential, current knowledge on the topic is still far from satisfactory. This work analyzes the contribution of starter cultures of Torulaspora delbrueckii, inoculated sequentially with Saccharomyces cerevisiae (multi-starter fermentation), on the fermentation and aromas of two different white style wines, i.e., dry and sweet wines. Chemical analysis of Soave and Chardonnay wines (dry wines) showed that multi-starter fermentation greatly affected the content of several important volatile compounds, including 2-phenylethanol, isoamyl acetate, fatty acid esters, C4–C10 fatty acids and vinylphenols. Moreover, strain-specific contributions have been shown by testing two different T. delbrueckii strains. Evidence of the positive impact of T. delbrueckii activity on wine quality was also demonstrated in Vino Santo, a sweet wine. Due to its low production of acetic acid, this non-Saccharomyces yeast is recommended for the fermentation of high sugar grapes. T. delbrueckii also influenced the content of different variety of chemical groups, including lactones. From a sensory perspective, all wines produced by multi-starter fermentation have greater aromatic intensity and complexity than wines resulting from a monoculture fermentation. These results emphasize the potential of employing T. delbrueckii, in association with S. cerevisiae, for the production of white wines of different styles with improved and enhanced flavour. © 2014, Springer Science+Business Media Dordrecht.

Azzolini M.,Centro per la Sperimentazione in Vitivinicoltura | Tosi E.,Centro per la Sperimentazione in Vitivinicoltura | Vagnoli P.,Lallemand Succursale Italiana | Krieger S.,Lallemand | Zapparoli G.,University of Verona
Italian Journal of Food Science | Year: 2010

The practice of inoculating selected bacteria before alcoholic fermentation (AF) (co-inoculation) to induce malolactic fermentation (MLF) was used to produce red table wines from several grape varieties. In most of the microvinification trials, MLF was completed before or within one week after de-vatting. The acetic acid content remained within an acceptable level (<0.60 g/L). In an industrial vinification (200 hL), MLF induced by co-inoculation was completed before de-vatting, while in the wines inoculated after AF, the total malic acid degradation was obtained 33 days later. The potential risk of increasing the volatile acidity was also evaluated by inducing MLF in partially fermented wines. The co-inoculation practice was compatible with the production of red wines. The decrease in vinification time with respect to traditional MLF management could offer a significant advantage for industrial wineries. © 2010.

Tosi E.,Centro per la Sperimentazione in Vitivinicoltura | Fedrizzi B.,University of Padua | Fedrizzi B.,Research and Innovation Center Fondazione Edmund Machinery | Azzolini M.,Centro per la Sperimentazione in Vitivinicoltura | And 3 more authors.
Food Chemistry | Year: 2012

The effects of noble rot on the overall quality of Amarone wine, a "Passito" dry red wine, produced by a traditional withering grape process are poorly understood. Wines obtained from healthy and selected grapes infected by noble rot were compared. Validation of the experimental plan was carried out by determining glycerol and gluconic acid content, laccase activity and microbial analysis of the musts. Botrytis cinerea infection produced significant variation in esterase and β-glucosidase activity of grape must. Aroma analysis in healthy and botrytised wines was carried out by SPE extraction followed by GC-MS quantification. A decrease of several fermentative esters was observed in botrytised wine, while wine produced from healthy grapes showed a higher fatty acid content. Molecules such as 1-octen-3-ol, phenylacetaldehyde and furaneol were positively linked to the noble-rotten grapes. Interestingly, γ-nonalactone and 4-carbethoxy-γ- butyrolactone increased, while sherry lactones decreased in botrytised wine. The strong increase of N-(3-methylbutyl)acetamide was related to B. cinerea grape infection. © 2011 Elsevier Ltd. All rights reserved.

Guzzo F.,University of Verona | Cappello M.S.,CNR Institute of Sciences of Food Production | Azzolini M.,Centro per la Sperimentazione in Vitivinicoltura | Tosi E.,Centro per la Sperimentazione in Vitivinicoltura | Zapparoli G.,University of Verona
International Journal of Food Microbiology | Year: 2011

The lysozyme of hen's egg white is used in winemaking to control spontaneous lactic acid bacteria (LAB). A total of eight LAB strains, isolated from grape must and wine, were used to assess the inhibitory effects of wine phenolics on lysozyme activity. The presence of phenolics, extracted from grape pomace, in growth medium reduced the mortality rate due to the lysozyme activity. This effect was especially clear in the case of strains belonging to Lactobacillus uvarum, Pediococcus parvulus and Oenococccus oeni, which are more sensitive to lysozyme than L. plantarum and L. hilgardii strains. Cell lysis assays carried out on four strains sensitive to lysozyme and Micrococcus lysodeikticus ATCC 4698, used as a reference strain, confirmed the inhibition of grape pomace phenolics on the muramidase. There was no interference from non-flavonoids, flavanols and flavonol compounds, when they were tested individually, on the lysozyme activity against the strains. Anthocyanins extracted from grape skins slightly inhibited the activity only against M. lysodeikticus. However, proanthocyanidins extracted from seed berries, strongly inhibited the lysozyme. In this extract, dimers were the predominant oligomers of flavan-3-ol. The study demonstrated that the effectiveness of lysozyme against LAB in red winemaking is related to the amount of low molecular weight proanthocyanidins that are released when the grapes are macerating. © 2011 Elsevier B.V.

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