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In this study, we performed an analytical and sensorial comparison between sparkling wines produced by the Traditional and Charmat methods using the same base wine, yeast strain, inoculum, and aged on the lees during the same periods. The absence of evident differences in the results of the analyses of physicochemical and volatile compounds was confirmed by the sensory analysis. In general, during the tests, more evaluators could identify differences in the first stages in which sensory analyses were performed. As the ageing time on the lees increase, fewer evaluators could differentiate between the sparkling wines. It was observed that more than half of the evaluators could not differentiate the samples in all stages. Based on our data, we conclude that the method used for the second fermentation is not the determinant of the eventual differences currently associated with sparkling wine produced by the Traditional and Charmat methods.

Considering the influence of natural yeasts on wine production and the organoleptic properties of the final product, the objective of the present study was to evaluate the diversity of yeasts in Cabernet-Sauvignon and Merlot (Vitis vinifera L.) grown in the highlands of the Northeast region of Rio Grande do Sul State, “Serra Gaúcha”, Brazil. Grape samples were collected from commercial vineyards between February and March in the 2017, 2018 and 2019 vintages. One hundred sixty-six isolated yeasts were classified at the species level by D1/D2 domain of 26S rRNA sequencing. A total of 31 yeast species were identified. The most prevalent species were Hanseniaspora uvarum, Issatchenkia terricola, Saturnispora diversa and Starmerella bacillaris. These same yeasts were the most frequent regardless of the year evaluated. The results indicated that there is a great diversity of yeast species in grapes cultivated in the highlands of Southern Brazil. However, the yeast communities remain similar in Cabernet-Sauvignon and Merlot grapes the analysed parameters (grape variety/vintage) are not interfering in the yeast populations found in the region highlands of Rio Grande do Sul, “Serra Gaúcha”, Brazil. This study enabled the knowledge of the yeast populations present in the region and their variations during the harvesting of wine grapes, showing that there is a majority pattern of species independent of the harvest.

Problems can often arise at the beginning of the second fermentation (prise de mousse) of sparkling wines, such as no start, a long lag period or slow fermentation. These problems are generally associated with yeast stress when inoculated in a base wine with high ethanol content and low pH. However, few studies focus on sulphites, which are often added to base wines to prevent malolactic fermentation, microbiological instability, and wine oxidation. This study aimed to evaluate the joint effect of ethanol and sulfur dioxide on yeasts during the second fermentation. For this purpose, yeasts (Saccharomyces cerevisiae EC1118) were subjected to ethanol, sulfur dioxide and ethanol/sulfur dioxide at the beginning of fermentation, and their vitality and viability, as well as the accumulation of intracellular reactive oxygen species and intracellular pH, were evaluated by flow cytometry. Furthermore, the expression of genes involved in sulfur transport and metabolism was determined. The results showed high mortality, ROS accumulation and intracellular pH reduction in fermentations with both ethanol and sulfur dioxide. The negative effect of ethanol, sulfur dioxide and ethanol/sulfur dioxide on yeasts was found to be dose-dependent and high in those commonly found in some base wines. Cells treated with ethanol/sulfur dioxide showed over-expression of genes involved in sulphite transport (SUL1 and SUL2), efflux pump (SSU1 and FZF1) and metabolism of sulfur amino acids (MET14). Altogether, our data indicate that ethanol and sulfur dioxide have a synergistic effect on yeasts, which may be the root cause of the problems encountered at the beginning of the second fermentation of sparkling wines, and should thus be seriously taken into consideration by winemakers.

In this study, we followed the yeast and wine behaviour during the second fermentation and subsequent lees ageing of sparkling wines produced by Traditional and Charmat methods at an industrial scale. During this period, we conducted physicochemical, microbiological, gene expression, and marker analyses of characteristics related to wine ageing. Our results show that the yeast behaviour during the fermentation is similar in both methods. However, after fermentation, there is a faster decrease in yeast vitality and viability in the Charmat method, together with an increase in the expression of autophagy-related genes (AMS1, APE1, and ATG8). We relate these factors to ageing with the continuous homogenization of the liquid practised in the Charmat method, and static ageing with the lees concentrated at the bottom of the bottle performed in the Traditional method. Despite the variation in yeast viability during ageing, there are no differences in soluble proteins, free amino nitrogen, total phenols, antioxidant activity, and colour evolution between the wines produced by the two methods, assuming few differences over the time that monitoring was conducted.

Mead or honey wine is an alcoholic beverage traditionally produced by the fermentation of a mixture of honey and water. Mead fermentation faces several problems that include sluggish and stuck ferm...

In our paper, we show that at a pH commonly found in sparkling base wines (i.e., 2.8-3.3), a synergism occurs between the SO2 added as a preservative and the ethanol present in the base wine. This synergism causes high stress on yeasts that lead to an important loss of viability, which in turn causes an increase in the lag phase time, slow fermentation and difficulties in finishing the prise de mousse.

Yeasts of the genus

Pyment is a type of mead that is produced from the alcoholic fermentation of a honey solution with the addition of grape juice. Due to the demand for new beverages, pyment can be a profitable alternative for both grape and honey producers. Therefore, this work aimed to characterize the aromatic and physicochemical composition of pyments. The pyments were prepared with addition of 10, 20 and 30% of Moscato juice, and compared with Moscato wine and traditional mead. The results showed an increase in the fermentation rates of Moscato-pyments, indicating that the addition of Moscato juice reverses the low fermentative vigor often reported in mead fermentations. Physicochemical parameters showed an increase in total acidity and a decrease in residual sugar and alcohol, depending on Moscato juice concentration. Moscato-pyments showed an intermediate concentration of volatile compounds between the traditional mead and Moscato wine, with a better balance between fruity, floral and buttery, manifesting characteristic aromas of wines made with Moscato grapes and simultaneously, exposing characteristic aromas of honey. The sensory analysis reveals a significant difference between mead, pyments and Moscato wine. In general, pyments were considered, by the panelists, as the most equilibrated with intermediary aroma intensity, floral, fruity and honey aromas, and good persistence in the mouth.

The aim of this study is to evaluate Muscat sparkling wines from the traditional Asti region (Italy) and the new geographical indication “IG Farroupilha” (Brazil). We analyzed 23 commercial Muscat sparkling wines from Asti and Farroupilha. Sample characterization of the aromatic profile by headspace-solid phase microextraction and gas chromatography detector yielded a total of 32 targeted components in Muscat wines. The multivariate analysis of data differentiates the Muscat sparkling wines based on origin: Brazilian or Italian. The main quantitative differences between wines are residual sugar, sulfite content, isoamyl acetate, hexyl acetate, limonene, rose oxide, linalool, and citronellol. The sensory analysis confirmed that Brazilian wines were less sweet with freshener aroma, whereas the Italian wines were more intense in aroma, complex, and sweet. These peculiarities can be associated with terroir, including technological processes that may be tailored to fit different wine styles for particular markets. Practical applications: The chemical and sensorial characterizations of sparkling wines produced in regions with geographical indication are important to differentiate products made in different regions.

Background and Aims Moscato Branco is the most important cultivar used in the production of Brazilian muscat sparkling wines and is responsible for their sensory characteristics. The aim of this work was to evaluate the effect of monoculture and co‐fermentations by Torulaspora delbrueckii (TPI‐4) and Saccharomyces cerevisiae (EC1118) on the physicochemical, aromatic composition and sensory characteristics of Moscato Branco wines. Methods and Results Wines inoculated with axenic and co‐inoculated with S. cerevisiae and T. delbrueckii were elaborated and subjected to physicochemical, chromatographic and sensory analysis. The monoculture fermentation with T. delbrueckii, and co‐fermentation with 25%EC1118/75%TPI‐4 showed the lowest concentration of volatile fatty acids, considered as undesirable compounds and the highest concentration of 2‐phenylethanol, acetates and ethyl esters, with fruity and flowery descriptors. Based on odour activity values, the main positive contribution of T. delbrueckii was on the concentration of isoamyl acetate, 2‐phenylethanol, 2‐phenylethyl acetate, ethyl hexanoate and linalyl acetate. Conclusions Wines produced by co‐fermentation with 25%EC1118/75%TPI‐4 obtained the highest general quality, aroma quality and flavour intensity scores in the sensory evaluation, reflecting the positive contribution of T. delbrueckii on the sensory attributes of Moscato Branco wines. Significance of the Study This work showed that co‐inoculation with T. delbrueckii and S. cerevisiae improves the quality of muscat wines.

The physicochemical characteristics and yeasts diversity in honey samples from 17 species of stingless bees of the genera Nannotrigona, Melipona, Plebeia, Scraptotrigona, and Tetragonisca cultivated in Southern Brazil were determined. The sugar content, moisture, water activity, pH, reducing sugars/total sugar ratio, and total yeast population varied significantly among the honey from the different bee species. The highest yeast population was found in the Plebeia's honey samples and correlated with their high water-activity. Sixteen yeast species were identified based on the nuclear large subunit (26S) ribosomal RNA partial sequences. The genera Starmerella and Zygosaccharomyces were found predominant, with a high prevalence of Starmerella sp., S. etchellsii, and S. apicola. Some yeast species were only identified in honey samples from specific bee species indicating a close relationship between the yeasts and the insects. For the first time, Wickerhamomyces sydowiorum in honey is being reported. In general, the yeast species isolated from stingless bee honey samples demonstrated high osmotolerance and low sugar assimilation.

Um ambiente salubre e fundamental para a manutencao da saude humana. Devido a isso, os Estados vem ao longo da historia buscando alternativas a fim de destinar adequadamente os residuos produzidos pela populacao. Nesse sentido, o ordenamento juridico brasileiro aprovou recentemente a Lei 11.445/2007, a qual e considerada o marco regulador no setor de saneamento basico no Brasil. Visando concretizar um direito constitucional, o Decreto 7.217 de 2010 estabeleceu prazo maximo para os municipios se adequarem a legislacao de modo a elaborarem seus Planos Municipais de Saneamento. Nesse contexto, este projeto de pesquisa tem como objetivo averiguar de que forma os municipios das Bacias dos rios Cai e Taquari-Antas estao cumprindo as determinacoes legais impostas pela legislacao brasileira. Para tanto sera realizada uma pesquisa aplicada, exploratoria e descritiva, cujos dados serao coletados por meio de um questionario enderecado as prefeituras dos municipios das Bacias dos rios Cai e Taquari-Antas via correio eletronico. Como resultado espera-se chegar a dados importantes quanto a elaboracao realidade dos municipios da regiao nordeste do estado do Rio Grande do Sul, no que se refere aos servicos de saneamento basico.