In recent years, there has been increasing concern about the impact of climate change on viticulture, in particular regarding its influence on grape maturity and quality. Extensive research has shown ...that the rise of temperatures during grape ripening accelerates the accumulation of sugars while reducing the synthesis of phenolic and aromatic compounds. The aim of this study was to investigate whether the foliar application of the plant growth regulator ethephon might delay technological grape maturity and increase grape phenolic content, improving wine quality. For this, different concentrations of ethephon were applied during two vintages to the Tempranillo grape variety at the onset of veraison. Results showed that grape sugar accumulation was delayed in one of the two vintages, whereas the treatment favored the accumulation of phenolic compounds in both vintages. In conclusion, the application of ethephon at the onset of veraison to Tempranillo grapevines helped to couple grape phenolic and technological maturity, leading to more balanced wines, either by delaying sugar accumulation or by enhancing the synthesis of anthocyanins and phenolic compounds.
Practical Application
Due to the current climate change, phenolic maturity of grapes does not match with their technological maturity, which means that harvested grapes are usually very sweet but without enough color and aroma. The foliar application of the plant growth regulator—ethephon—delays technological grape maturity and increases grape phenolic content, improving wine quality and creating wines that are more balanced.
•First work to study carbonic maceration in Tempranillo and Graciano simultaneously.•Carbonic maceration greatly influences red wine color parameters.•Wine phenolic composition depended on the ...fraction obtained by carbonic maceration.•Wines were clearly discriminated according to their phenolic composition.
The current study aims to gather information about the color-related characteristics and the monomeric phenolic composition of carbonic maceration (CM) wines. The study was conducted over two vintages, with two different grape varieties. Color-related general parameters and wine monomeric phenolic composition were determined in both free-run and press CM fractions and were compared to conventional winemaking (CW). Overall, wines made by CM had lower phenolic content and color intensity. The analysis of wine detailed phenolic composition showed that CM wines were characterized by low contents of anthocyanins and flavonols. In contrast, free-run wine obtained by CM had the greatest concentration of flavanols and hydroxycinnamic acids, probably due to the presence of stems during the fermentation. In conclusion, vinification by CM leads to important differences in wine phenolic composition and, as consequence, on wine color properties. These differences could play an important role in wine sensorial properties and wine aging potential.
•Vinification by carbonic maceration is a useful tool for the reduction of the alcohol content of wines.•Carbonic maceration winemaking would allow different wines to be obtained from one ...vinification process.•Low alcohol wines obtained by CM show less aromatic and colour loss than with other dealcoholisation techniques.•The reduction in alcoholic strength by CM varies according to the grape variety and winemaking conditions.
The increase in alcohol content in wine due to climate change is one of the main challenges that winemakers face today. Previous studies have indicated that carbonic maceration processing can be used to obtain a wine fraction with lower alcoholic strength. The aim of this study was to determine the effectiveness of this technique in obtaining wines with lower alcohol content. For this purpose, seven trials were carried out, studying a total of 63 wines. The physico-chemical, phenolic and aromatic composition of the wines was analysed using official methods and gas chromatography. The results showed that it is possible to obtain a fraction of carbonic maceration wine (25–35% of the total) with a reduction in alcohol content of up to almost 4% depending on the vinification conditions and the grape variety used. Therefore, this CM fraction, marketed on its own, could be a low-alcohol alternative to red wines.
Nine non-Saccharomyces yeasts belonging to 6 species (Torulaspora delbrueckii, Metschnikowia pulcherrima, Lachancea thermotolerans, Zygosaccharomyces bailii, Williopsis pratensis and Candida ...zeylanoides) and two mixed inoculum of T. delbrueckii and L. thermotolerans were screened for aroma formation and fermentative behaviour in sequential inoculations with Saccharomyces cerevisiae. The main differences in aromatic composition within wines were detected in the first stages of vinification between S. cerevisiae and non-Saccharomyces species, but not within the latter species. Most of the wines made with non-Saccharomyces in sequential fermentation with S. cerevisiae tended to produce higher ethanal and glycerol and lower volatile acidity than those inoculated only with S. cerevisiae. However, no significant differences were found in alcohol content. The addition of S. cerevisiae tended to standardise the wines and only those made with T. delbrueckii and L. thermotolerans, both alone and together, showed different aromatic profiles. Wines elaborated with non-Saccharomyces yeasts that quickly decreased in tanks showed characteristics similar than those made only with S. cerevisiae. Therefore, sequential inoculation of non-Saccharomyces/Saccharomyces is a useful tool to modulate wine characteristics, but only with species which remain longer in tanks. These findings can be useful to carry out selection processes within these species.
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•The presence of non-Saccharomyces in tanks for a long time is required to modulate wine aroma.•The mixed T. delbrueckii/L. thermotolerans inoculum kept the initial proportions.•Mixed T. delbrueckii/L. thermotolerans inoculum contribute less to aroma than pure cultures.•Non-Saccharomyces /Saccharomyces produced higher ethanal and glycerol than S. cerevisiae.•Non-Saccharomyces/Saccharomyces produced lower volatile acidity than S. cerevisiae.
The phenolic compounds of red wines are responsible for their color, astringency, and antioxidant properties. The fermentative yeasts might be used to modulate wines in terms of their color, aroma ...and probably healthy properties. In this study, six non-
species were tested because they might enhance the properties of red Tempranillo wines from Rioja. The results confirmed that the anthocyanins and stilbenes composition of wine can be modulated with the use of a specific fermentation starter.
,
,
, and
achieved the greatest improvements of the monomeric anthocyanin composition, and the latter three yeast species achieved the best results of stilbene composition when compared to
and the other non-
yeasts. Overall, results suggested that the use of
and
as fermentation starters could be of great interest to achieve wines with better color and likely healthy properties.
The aim of the study was to determine the relevance of microorganisms present during the carbonic maceration vinification in the specific attributes of young red wines produced by this method. For ...this purpose, wines were made by the two winemaking methods: carbonic maceration and the standard method of destemming and crushing, starting from the same batch of grapes. The microbiological population of the initial grapes was homogenised by means of a “pied de cuve”, and afterwards, the microbial evolution (yeasts, lactic acid and acetic acid bacteria) was followed in different fermentation stages. Finally, the wines obtained were analysed and tasted. After homogenising the initial microbiota, small microbiological differences were detected both in the counts of microorganisms and in the species involved. Nevertheless, the wines obtained were remarkably different, both in their chemical composition and in their organoleptic characteristics. This would indicate that, although the microbiota present could influence some of the characteristics of carbonic maceration wines, the main factor that determines the unique characteristics of these wines is their particular production procedure based in the intracellular fermentation.
•Carbonic Maceration (CM) wines are special in chemical and organoleptic characteristics.•No differences were detected in microorganisms involved in CM and in traditional methods.•Characteristics of CM wines are due to winemaking method based in intracellular fermentation.•CM vinification makes possible to obtain a part of wine with a lower alcohol content.
•CM wines presented higher total content of aromatic esters and acetates.•CM wines showed higher polyphenol content and ionization and polymerization rates.•CM wines had higher antioxidant ...activity.•Vitisins A and B and coumaroyl derivatives of anthocyanins were increased by CM process.
The aim of the study was to determine the differences in the microbiological, physical-chemical, aromatic and phenolic composition between two winemaking methods: carbonic maceration and the standard method of destemming and crushing. We analysed 84 commercial Rioja wines made from the Tempranillo grape variety during the 2017 vintage, 40 had been made by carbonic maceration and 44 by destemming and crushing. Despite the heterogeneity within the two groups of wines, it was possible to differentiate between them. Wines made by carbonic maceration presented higher aromatic quality due to their higher total content of esters and acetates, as well as a greater colour intensity due to a higher phenolic content and higher rates of ionization and polymerization. In addition, it was observed that the antioxidant activity, the content in coumaroyl derivatives of anthocyanins and the vitisins A and B were considerably greater in wines made by carbonic maceration.
During wine stabilization, control of the microbial population is required in order to ensure a quality wine. Pulsed Electric Field (PEF) was applied to commercial wines in a continuous flow to ...reduce the amount of SO2 added after the end of malolactic fermentation to manage microbial populations. Samples of wine from three commercial wineries of the Rioja Qualified Designation of Origin were treated with 30 mg/L SO2, with 15 mg/L SO2 and PEF, and only with PEF. The inactivation of the microbiota with the PEF treatment was greater than the inactivation achieved with SO2 four days after treatment. Six months later, the lactic acid bacteria population was still viable in some of the wines. Regarding the physicochemical characterization of the wines, the PEF treatment was positive for quality because the wines had greater color intensity and lower volatile acidity. Moreover, organoleptic analysis indicated different scoring depending mainly on the characteristics of the original wine. Despite these positive results, further studies are advisable to optimize the control of lactic acid bacteria.
The application of PEF during wine stabilization after MLF can be a viable alternative for the oenological industry to reduce the SO2 dosage used in winemaking.
•PEF technology was effective for reducing the SO2 dosage.•PEF technology achieved an important inactivation of microorganisms.•LAB remained viable in wines six months after treatment.•PEF treatment caused an increase in the color intensity.•PEF treatments did not alter the organoleptic wine quality.
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