Resumen
En este trabajo se buscó a través de la combinación de 2 estrategias reducir el contenido de alcohol en vinos de la variedad Tannat. La primera estrategia consistió en el screening dentro de ...clones uruguayos de Tannat Con este fin se muestrearon durante tres vendimias consecutivas 10 clones uruguayos de Tannat y se utilizó como referencia el clon francés 717 en viñedos. De los clones estudiados 4 presentaron durante la vendimia 2023 un contenido significativamente inferior de alcohol que el clon 717, manteniendo los componentes responsables de su calidad sensorial (aromas glicosidados, antocianos totales). Mientras que la segunda estrategia fue realizar un screening de levaduras no-
Saccharomyces
nativas aisladas de viñedos uruguayos para utilizar en conjunto con la cepa
Saccharomyces cerevisiae
Lalvin BM4x4 Lalleman (utilizada como referencia para vinificar vino Tannat). Se estudió el comportamiento de 4 géneros de levaduras (
Candida zemplinina, Metschnikowia pulcherrima, Metschnikowia fructicola y Hanseniaspora uvarum
), en microvinificaciones en símil vino. Estas estrategias fueron seleccionada por que además de permitir la reducción de alcohol en vinos Tannat en forma conjunta le aportan una identidad propia de nuestro país.
The aim of this study was to reduce the alcohol content of Tannat wines through a combination of two strategies. The first strategy consisted of screening within Uruguayan Tannat clones. To this purpose, 10 Uruguayan Tannat clones were sampled during three consecutive vintages and the French clone 717 was used as a reference in vineyards. Of the clones studied, 4 showed significantly lower alcohol content than clone 717 during the 2023 vintage, while maintaining the components responsible for their sensory quality (glycosidic aromas, total anthocyanins), while the second strategy was to screen native non-Saccharomyces yeasts isolated from Uruguayan vineyards for use in conjunction with the
Saccharomyces cerevisiae
Lalvin BM4x4 Lalleman strain (used as a reference for vinifying Tannat wine). The behaviour of 4 yeast genera (
Candida zemplinina, Metschnikowia pulcherrima, Metschnikowia fructicola and Hanseniaspora uvarum
) was studied in wine-like microvinifications. These strategies were selected because they allow the reduction of alcohol in Tannat wines and, together, they give the wine a unique character of our country.
Resumen
La variedad Tannat desde el punto de vista del aroma, resulta una variedad neutra pero capaz de aportar precursores aromáticos que son de interés en la elaboración de vinos de guarda. Los ...principales precursores aromáticos presentes son compuestos glicosidados y carotenoides. Durante 3 vendimias consecutivas se estudió el contenido de precursores aromáticos de 8 clones comerciales de Tannat (ENTAV-INRA: 398, 399, 472, 474, 475, 717, 794 Y 944). En base a los resultados obtenidos se seleccionaron los clones 717 y 474 por su alta y baja performance en la producción de precursores glicosidados. En la siguiente vendimia se estudió el comportamiento de precursores glicosidados (SPE-GC-MS) y carotenoides (HPLC-DAD) en los clones seleccionados durante 4 estadíos de madurez de la uva, donde se identificaron 14 xantofilas y 1 caroteno. Se encontraron diferencias significativas en el contenido de carotenoides entre los dos clones estudiados a lo largo del período de maduración. Mientras que su degradación no presentó diferencias significativas. Conjuntamente se identificaron 10 norisoprenoides glicosidados en la uva de los clones estudiados pero el contenido de estos no presentó diferencias significativas entre los clones durante está vendimia. Las diferencias entre los clones 717 y 474 son tales que no se expresan todos los años teniendo variabilidad con el año y donde el clima juega un rol fundamental.
Abstract
From the viewpoint of aroma, the Tannat is a neutral variety but it is capable of providing aromatic precursors that are of interest in the production of wines for ageing. The main aromatic precursors present are glycosidic compounds and carotenoids. The content of aromatic precursors of 8 commercial Tannat clones (ENTAV-INRA: 398, 399, 472, 474, 475, 717, 794 and 944) was studied during 3 consecutive harvests. Based on the results obtained, clones 717 and 474 were selected for their high and low performance in the production of glycosidic precursors. In the following vintage, the behaviour of glycosidic precursors (SPE-GC-MS) and carotenoids (HPLC-DAD) was studied in the selected clones during 4 stages of grape maturity, where 14 xanthophylls and 1 carotene were identified. Significant differences in carotenoid content were found between the two clones studied throughout the ripening period. While their degradation did not show significant differences. Jointly, 10 glycosidised norisoprenoids were identified in the grapes of the clones studied, but the content of these did not show significant differences between the clones during this harvest. The differences between clones 717 and 474 are such that they are not expressed every year, having variability with the year and where climate plays a fundamental role.
Recently, the increase in microbreweries and the consequent production of craft beers have reached exponential growth. The interest in non-conventional yeasts for innovation and a unique selling ...feature in beer fermentation is increasing. This work studied the autochthonous Saccharomyces and non-Saccharomyces yeasts, isolated from various food sources, with the ability to modify and improve the fermentative and aromatic profiles during alcoholic fermentation. The ability to ferment maltose and produce desirable aroma compounds were considered as the key characters for the screening selection. A synthetic beer wort was developed for this purpose, to simulate beer wort composition.
A total of forty-seven yeast strains belonging to different genera were analysed according to their fermentation profile, volatile compounds production and sensory analysis. Three native strains of Saccharomyces cerevisiae, Zygoascus meyerae and Pichia anomala were selected to evaluate their aromatic profile in single and mixed fermentations. The strains produced 4-vinylguaiacol, β-phenylethyl alcohol, and isoamyl alcohol at levels significantly above the sensory threshold, making them interesting for wheat and blond craft beer styles. The native Hanseniaspora vineae was also included in a co-fermentation treatment, resulting in a promising yeast to produce fruity beers.
•A synthetic beer wort was developed to simulate beer wort composition.•Z. meyerae, P. anomala and H. vineae were the selected non-conventional yeasts.•Aroma compounds produced were promising for wheat and blond craft beer styles.•High ester production by Hanseniaspora vineae is promising for fruity beers.
•Application of yeast Hanseniaspora vineae in real wine co-fermentation.•H. vineae and spontaneous fermentations showed higher flavour intensity and diversity.•Genetic strains identification showed ...increased diversity compared to conventional treatment.•Increased formation of esters and decrease formation of alcohols may explain fruit intensity.
Discovery, characterisation and use of novel yeast strains for winemaking is increasingly regarded as a way for improving quality and to provide variation, including subtle characteristic differences in fine wines. The objective of this work was to evaluate the use of a native apiculate strain, selected from grapes, Hanseniaspora vineae (H. vineae) 02/5A. Fermentations were done in triplicate, working with 225L oak barrels, using a Chardonnay grape must. Three yeast fermentation strategies were compared: conventional inoculation with a commercial Saccharomyces cerevisiae strain, ALG 804, sequential inoculation with H. vineae and then strain ALG 804 and spontaneous fermentation. Yeast strain identification was performed during fermentation, in which the apiculate strain was found to be active, until 9% of alcohol in volume, for the co-fermentation and the spontaneous fermentation was completed by three native S. cerevisiae strains. Basic winemaking parameters and some key chemical analysis, such as concentration of glycerol, biogenic amines, organic acids, and aroma compounds were analysed. Sensory analysis was done using a trained panel and further evaluated with professional winemakers. Sequential inoculation with H. vineae followed by S. cerevisiae resulted in relatively dry wines, with increased aroma and flavour diversity compared with wines resulting from inoculation with S. cerevisiae alone. Wines produced from sequential inoculations were considered, by a winemaker’s panel, to have an increased palate length and body. Characteristics of wines derived from sequential inoculation could be explained due to significant increases in glycerol and acetyl and ethyl ester flavour compounds and relative decreases in alcohols and fatty acids. Aroma sensory analysis of wine character and flavour, attributed to winemaking using H. vineae, indicated a significant increase in fruit intensity described as banana, pear, apple, citric fruits and guava. GC analysis of the relative accumulation of 23 compounds to significantly different concentrations for the three fermentation strategies is discussed in relation to aroma compound composition.
Tannat (Vitis vinifera) es la variedad de vid vinífera más cultivada en Uruguay para la producción de vinos tintos de alta calidad. Sus bayas poseen niveles de compuestos polifenólicos (antocianinas ...y taninos) inusualmente altos, produciendo vinos con intenso color púrpura y alto poder antioxidante. Pero es considerada una variedad no aromática. Los taninos dan estructura en boca a los vinos, se sintetizan en las semillas antes de envero y en Tannat más de un 40% están galoileados, lo que determina un mayor poder antioxidante. Las antocianinas dan color a la piel de las uvas y al vino y su síntesis comienza durante el envero. Secuenciamos el genoma de Tannat con una profundidad de 134X. Secuenciamos trancriptomas de cáscaras y semillas a lo largo del desarrollo de la baya. El objetivo es dilucidar las bases genómicas y transcriptómicas de las particularidades de Tannat. Al comparar su genoma con el de Pinot Noir (genoma de referencia) encontramos una expansión de las familias génicas relacionadas con la biosíntesis de polifenoles. Análisis de los patrones de expresión diferencial asociados a estudios metabolómicos (HPLCMS) nos permitieron asignar funciones a genes antes desconocidas; y la participación de genes nuevos (no anotados previamente en el genoma de referencia) y varietales (ausentes en el genoma de referencia) en la biosíntesis de los polifenoles característicos de Tannat. Nuestros trabajos realizan aportes originales acerca de las bases moleculares de la biosíntesis de antocianinas y taninos durante el desarrollo de la uva vinífera insignia del Uruguay.
Vinifications were conducted using pure cultures of
Saccharomyces cerevisiae
, and mixed cultures by sequential inoculation of a
Hanseniaspora vineae
(T02/05F) and
Hanseniaspora clermontiae
...(A10/82F), with a
Saccharomyces cerevisiae
conventional strain. The vinification systems applied to Tannat grapes were defined: semipilot, pilot and industrial scale. Fifty-one volatile compounds were identified in all the vinifications, sixteen of them were above the aroma threshold values and potentially contributed to the final sensory profiles. A sensory characterization of aroma was carried out using the projective mapping technique, with forty-eight consumers who made evaluation of the three vinifications. Multiple factorial analysis was used to compare the chemical and sensory data to find correlations. The results obtained from both methodologies were coincident, confirming the aromatic tendencies found in the different vinifications. Both studies demonstrated that wines obtained by semipilot scale was characterized by descriptors associated with “chemical” and “floral”; those from pilot vinification by the “spicy” descriptor; while industrial vinification produced wines described as “fruit” and “wood”.
Study of secondary grape metabolites, such as polyphenol compounds (anthocyanins, flavonols, flavan-3-ols), volatile compounds present in grapes in both free and glycoside forms (monoterpenols, ...norisoprenoids, benzenoids), allowed us to characterize grape varieties and to suggest the best winemaking practices to maximize their enological potential. The
Vitis viníferas
studied in the present work are less frequent red grape varieties cultivated in small vineyards in southern Uruguay (Montevideo and Canelones Provinces): Ancellota, Aspiran Bouschet (syn. Lacryma Christi), Marselan (Grenache × Cabernet Sauvignon), Arinarnoa (Tannat × Cabernet Sauvignon), Egiodola (Abouriou × Tinta Negra Mole) and Caladoc (Malbec × Grenache).
Tannat ( Vitis vinifera ) is the most cultivated grapevine variety in Uruguay for the production of high quality red wines. Its berries have unusually high levels of polyphenolic compounds ...(anthocyanins and tannins), producing wines with intense purple colour and high antioxidant properties. Remarkably, more than 40% of its tannins are galloylated, which determines a greater antioxidant power. Technologies of massive sequencing allow the characterization of genomic variants between different clutivars. The Tannat genome was sequenced with a 134X coverage using the Illumina technology, and was annotated using transcriptomes (RNA-Seq) of different berry tissues. When comparing the genomes of Tannat with Pinot Noir PN40024 (reference genome) we found an expansion of the gene families related to the biosynthesis of polyphenols. A search base on the recently reported epicatechin galloyl transferase (ECGT) from tea leaves determined five putative genes encoding the ECGT in Tannat. Genetic analysis of one of the transcription factor that regulates the anthocyanin synthesis during berry ripening, VvMYBA1, shows the presence of Gret1 retrotransposon in one of the VvMYBA1 alleles in the Tannat clones analysed. This work makes original contributions about the molecular bases of the biosynthesis of anthocyanins and tannins during the development of the flagship grape of Uruguay.
Flavour and some compounds associated with wine colour are known to be yeast strain-dependent. These metabolites are important for the sensory quality of wines, studies searching for increase aroma ...and color are a key area today in winemaking. The aim of this work was to study the oenological potential of the two main strains of Hanseniaspora vineae,native to Uruguay to better understand their successful application at winery level. It is known that these strains contribute with extracellular proteases and β-glucosidase enzyme activities that might increase cell lysis and flavor depending in grape varieties. Application and nutrient management of the process of these strains in production of white wines (Chardonnay, Macabeo and Petit Manseng) and red wine Tannat are discussed. Wines were evaluated to determine the volatile compounds composition and their effect compared to conventional processes. Low production of short and medium chain fatty acids and ethyl esters, and high production of acetate esters and isoprenoids are found compared to S. cerevisiaestrains. The most outstanding characteristic of the species H. vineaewas the production of benzenoids, phenylpropanoids and acetate esters. This behavior was reflected in the sensory evaluation, where all the fermentations performed with H. vineaewere considered superior compared to Saccharomyces cerevisiaewine strains.
A new method was developed for analysing 4-ethylguaiacol and 4-ethylphenol in the aroma of red wines using dispersive liquid–liquid microextraction (DLLME) coupled with gas chromatography–mass ...spectrometry detection (GC–MS). Parameters such as extraction solvent, sample volume and disperser solvent were studied and optimised to obtain the best extraction results with the minimum interference from other substances, thus giving clean chromatograms. The response linearity was studied in the usual concentration ranges of analytes in wines (50–1500
μg/L). Repeatability and reproducibility of this method were lower than 5% for both volatile phenols. Limits of detection and limits of quantification were also determined, and the values found were 28 and 95
μg/L for 4-ethylguaiacol and 44 and 147
μg/L for 4-ethylphenol, respectively. This new method has been used for the determination of the volatile phenols concentration in different samples of Tannat wine affected by
Brettanomyces contamination.
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