Cotea Valeriu V.

The Production of Low-Alcohol Wines by Sequential Semi-Anaerobic Must Fermentation

Vasile Răzvan Filimon, Roxana Mihaela Filimon, Ancuța Nechita, Florin Dumitru Bora, Liliana Rotaru, Valeriu V. Cotea

ABSTRACT. Nowadays, consumers go towards products that provide food security and nutritional richness, consumption of highly alcoholic beverages not complying with these health-related requirements. This study aimed to obtain low-alcohol wines by performing sequential alcoholic fermentation of grape must (Muscat Ottonel). Thus, 11 commercial yeast strains (10 Saccharomyces cerevisiae and 1 Torulaspora delbrueckii) were preliminarily tested in anaerobic and semi-anaerobic conditions. Based on laboratory tests, grape must fermentation was sequentially initiated in semi-anaerobic conditions (loose cotton plugs; intermittent homogenization), with the T. delbrueckii strain (106 CFU/mL) and the addition of preliminarily selected S. cerevisiae strains (104 CFU/mL), to the consumption of 50% of the sugars in the must, to complete the fermentation. By applying this technology, dry wines were obtained with an alcohol content lower by up to 1.10% vol., but with a lower concentration of volatile terpenes, due to additional must oxidation. Also, semi-anaerobiosis enhanced glycerol synthesis by yeasts (< 35%), with a positive impact on the sensory characteristics of the wine. Keywords: alcoholic fermentation; glycerol; low-alcohol wine; non-Saccharomyces yeast; Torulaspora delbrueckii.

* Abstract published in Conference Programme dedicated to LIFE SCIENCES TODAY FOR TOMORROW

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The Aromatic Profile of White Wines Obtained from Biodynamic and Conventional Grown Grapes in Romania

Ana Maria Toader, Cintia Lucia Colibaba, Camelia Elena Luchian, Andreea Popîrdă, Bogdan Nechita, Valeriu V. Cotea

ABSTRACT. This study analyses the differences between wines obtained from grapes cultivated conventionally and those cultivated biodynamically. The wine samples studied were obtained from Rhein Riesling, Italian Riesling, Muscat Ottonel and Chardonnay grape varieties. Among these, four variants (one from each grape variety) were obtained from grapes following conventional cultural technologies, while the rest were from the same grape varieties cultivated biodynamically. All grapes and wines were produced in the Murfatlar vineyard, in south-east Romania. Basic chemical and sensorial analyses were applied to evaluate the differences appearing between the conventional and organic wine samples. All sets of data, PCA analysed, underlined that there are no systematic differences between the two grape cultivation methods and the obtained products.

Keywords: biodynamic grapes; organic vs. conventional wine; chemical composition; sensory profile.

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Studies on Some Still Wines Obtained by the Blanc de Noirs Method

Dragoș Florin Grosaru, Camelia Elena Luchian, Elena Cristina Scutarasu, Lucia Cintia Colibaba, Cătălin Ioan Zamfir, Valeriu V. Cotea

ABSTRACT. Consumer interest in innovative wines has increased in recent years in Romania, in correlation with the development of the wine sector. Nowadays, the winemaking technique proposed by Dom Perignon (blanc de noirs) with applicability to sparkling wines is increasingly used to obtain still wines. This research aimed to identify the most suitable technology for obtaining white wines from Fetească neagră and Busuioacă de Bohotin grapes. The resulting wines were analysed from physical-chemical and chromatic points of view, and their sensory properties and volatile compounds content were also registered. The obtained samples had characteristics usually found in wines obtained from white grape varieties. Although frequently used in the production of base wine for sparkling wines, this technique can give original results in obtaining still wines as well. The use of activated carbon has led to the production of wines with a higher commercial value (improved colour characteristics). Given that red wines are significantly less consumed compared to white ones, this technique allows the use of black grape varieties and the production of innovative white wines.

Keywords: blanc de noirs; Busuioacă de Bohotin; Fetească neagră; winemaking.

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Evaluation of Phenolic Compounds in White Wines Treated with Enzymes

Elena Cristina Scutarașu, Valeriu V. Cotea, Camelia Elena Luchian, Lucia Carmen Trincă, Andrei Scutarașu

ABSTRACT. Wine’s quality is influenced both by the grape characteristics and winemaking protocols. Awareness of the significant role of enzymes preparations in beverages technologies contributes to the optimization of the manufacturing process, for improving the chemical composition of the resulting wine and its organoleptic properties. This paper focuses on monitoring the impact of different commercial enzymes (pectinases and β-glycosides) on the main phenolic compounds content of Sauvignon blanc wines. For this experiment, ten phenolic compounds were quantified using a liquid-chromatography (LC) system coupled with ion trap mass spectrometer. The results indicated a significant influence of enzymes on wine’s phenolic fraction. Experimental samples presented high content in protocatechuic acid (9.99 – 13.75 μg/mL) and caftaric acid (2.69 – 9.80 μg/mL). The use of pectinases lead to an increase of phenolic compound’s concentration compared to the control.

Keywords: enzymes, wine, phenolic compounds, pectinases, β-glycosides.

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The Effect of Different Techniques of Maceration-Fermentation on the Phenolic Composition of Red Wines

Maria Iulia Cerbu, Valeriu V. Cotea, Cătălin-Ioan Zamfir, Marius Niculaua, Ioana Călin, Andreea Popîrdă, Cintia Lucia Colibaba, Ștefan Tudose Sandu-Ville

ABSTRACT. Grapes, the quintessential quality factor in winemaking, are found in certain areas of the globe where viticulture thrives. The quality of wine products is directly influenced by the quality of the grapes, their process technology, the care and the quality of the premises and equipment used, as well as the conditions for the storage and use of the wines. In most red wine-making processes, it is preferred that the maceration process is accompanied by the fermentation process, as increase in the alcohol content favours the intensification of the extraction process. For this reason, both processes are combined in a single technological operation known as maceration-fermentation. The largest amount of polyphenolic compounds of wine, anthocyanins and tannins comes from the solid parts of the grapes ‒ the skins and seeds, and these have a decisive influence on the phenolic character of wines. Maceration is a fractional extraction which leads to the dissolution of the useful components of the grapes, which give the flavour, colour and taste typical of red wine. The aim of this research was to analyse the effect of different techniques of maceration-fermentation on the phenolic composition of red wines obtained from Merlot, Pinot noir and Cabernet Sauvignon grape varieties in Copou-Iasi vineyard compared to red wines obtained from the same varieties in Murfaltar vineyard, located in the northeast and south of Romania, respectively. Wines obtained by maceration-fermentation in rotating tanks have higher values of the Folin-Ciocâlteu index (wines obtained from Pinot noir) in contrast to those obtained by the classical maceration-fermentation technique (wines obtained from Merlot and Cabernet Sauvignon).

Keywords: maceration; phenolic compounds; red wines; tannins; anthocyanins.

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