Terroir 1996 banner
IVES 9 IVES Conference Series 9 La vinificación de las uvas aromáticas: Moscateles y Malvasías

La vinificación de las uvas aromáticas: Moscateles y Malvasías

Abstract

Las uvas aromáticas se pueden dividir en dos clases, Moscateles y Malvasías, dependiendo del hecho de que el linalol o el geraniol, respectivamente, sean los alcoholes terpénicos monohidroxilados que predominan en el jugo de la uva. Dentro de cada clase existen numerosas subclases que se diferencian por las relaciones entre los otros alcoholes terpénicos mono y dihidroxilados, en forma libre y glicosilada. Otra diferencia entre los Moscateles y las Malvasías es la cantidad de compuestos terpénicos libres del mosto, (los terpenos del hollejo, en las dos clases, se encuentran casi en su totalidad como formas glicosiladas) que puede ser alto como en el caso del Moscatel (linalol, óxido trans piránico del linalol, 2,6-dimetil-3,7-octadien-2,6-diol) o mas bién bajo como en el caso de las Malvasías (geraniol, 2,6-dimetil-3,7-octadien-2,6-diol), mientras que en los hollejos es una característica común a las dos clases la presencia de elevadas cantidades de nerol y de geraniol en forma glicosilada. La composición terpénica de las dos variedades condiciona, además del aroma del vino final, la tecnología de producción.En Italia con el “Moscato bianco” y con las Malvasías (“Malvasia di Casorzo”, “Malvasia di Castelnuovo don Bosco”, esta última en muchos aspectos parecida a los Moscateles, “Brachetto d’Acqui”, que son todas variedades tintas) se preparan dos tipos de vino: uno espumoso y uno no espumoso. El primero se caracteriza por un contenido alcohólico de aproximadamente un 7%y una concentración de azúcares de aproximadamente 70 g/L y el segundo por un grado alcohólico del 5 % y una cantidad de azúcares variable dependiendo de los gustos del productor.En la vinificación del “Moscato bianco” se utiliza solo el mosto (una eventual criomaceración no conlleva un aumento sensible en compuestos terpénicos), que es rico de linalol que no resulta ni absorbido ni metabolizado por las levaduras, mientras que en el caso de las Malvasías tintas, para cuya vinificación se utilizan también los hollejos, el geraniol, practicamente el único alcohol terpénico monohidroxilado presente en el mosto, es metabolizado parcialmente por las levaduras y en parte reducido a citronellol y estos dos compuestos, además del nerol, son transformados en derivados acetilados. Además, a causa de las elevadas cantidades de glucosa que se encuentran en el mosto durante toda la fase de preparación de los vinos de estas variedades, los enzimas glicosidásicos, del mosto o de las levaduras, no pueden transformar en los respectivos aglicones los glicósidos del nerol y del geraniol presentes en el mosto, que quedan, por lo tanto, en forma glicosilada, es decir, no aromática, en el vino final. Las técnicas tradicionales de vinificación establecen, para la extracción del color y de los compuestos terpénicos de los hollejos de las Malvasías tintas, continuos remontados cuando la fermentación todavía no ha empezado, o una fermentación parcial en presencia de los hollejos. Estas dos técnicas son insuficientes sea para extraer la gran cantidad de glicósidos del nerol y del geraniol de los hollejos, sea para hidrolizar los glicósidos terpénicos. En este trabajo se presenta una nueva técnica de vinificación, que favorece la extracción y la hidrólisis de los compuestos terpénicos de los hollejos de las Malvasías tintas y que incrementa sensiblemente la intensidad del aroma y la calidad de los vinos que se obtienen con esta variedad.

DOI:

Publication date: February 24, 2022

Issue: Terroir 2000 

Type: Article

Authors

Rocco Di Stefano*, Emilia García Moruno* and Monica Ribaldone**

*Istituto Sperimentale per l’Enologia, via P. Micca 35 — 14100 Asti (Italia)
**Consorzio per la tutela del Brachetto

Tags

IVES Conference Series | Terroir 2000

Citation

Related articles…

The rootstock, the neglected player in the scion transpiration even during the night

Water is the main limiting factor for yield in viticulture. Improving drought adaptation in viticulture will be an increasingly important issue under climate change. Genetic variability of water deficit responses in grapevine partly results from the rootstocks, making them an attractive and relevant mean to achieve adaptation without changing the scion genotype. The objective of this work was to characterize the rootstock effect on the diurnal regulation of scion transpiration. A large panel of 55 commercial genotypes were grafted onto Cabernet Sauvignon. Three biological repetitions per genotype were analyzed. Potted plants were phenotyped on a greenhouse balance platform capable of assessing real-time water use and maintaining a targeted water deficit intensity. After a 10 days well-watered baseline period, an increasing water deficit was applied for 10 days, followed by a stable water deficit stress for 7 days. Pruning weight, root and aerial dry weight and transpiration were recorded and the experiment was repeated during two years. Transpiration efficiency (ratio between aerial biomass and transpiration) was calculated and δ13C was measured in leaves for the baseline and stable water deficit periods. A large genetic variability was observed within the panel. The rootstock had a significant impact on nocturnal transpiration which was also strongly and positively correlated with maximum daytime transpiration. The correlations with growth and water use efficiency related traits will be discussed. Transpiration data were also related with VPD and soil water content demonstrating the influence of environmental conditions on transpiration. These results highlighted the role of the rootstock in modulating water deficit responses and give insights for rootstock breeding programs aimed at identifying drought tolerant rootstocks. It was also helpful to better define the mechanisms on which the drought tolerance in grapevine rootstocks is based on.

Climate modeling at local scale in the Waipara winegrowing region in the climate change context

In viticulture, a warming climate can have a very significant impact on grapevine development and therefore on the quality and characteristics of wines across different spatial scales, ranging from global to local. In order to adapt wine-growing to climate change, global climate models can be used to define future scenarios, but only at the scale of major wine regions. Despite the huge progress made over the last ten years in terms of the spatial resolution of climate models (now downscaled to a few square kilometres), they are not yet sufficiently precise to account for the local climate variability associated with such parameters as local topography, in spite of these parameters being decisive for vine and wine characteristics. This study describes a method to downscale future climate scenarios to vineyard scale. Networks of data loggers have been used to collect air temperature at canopy level in the Waipara winegrowing region (New Zealand) over five growing seasons. These measurements allow the creation of fine-scale geostatistical models and maps of temperature (at 100 m resolution) for the growing season. In order to model climate change at pilot site scale, these geostatistical models have been combined with regional climate change predictions for the periods 2031-2050 and 2081-2100 based on the RCP8.5 climate change scenario. The integration of local climate variability with regionalized climate change simulations allows assessment of the impacts of climate change at the vineyard scale. The improved knowledge gained using this methodology results from the increased horizontal resolution that better addresses the concerns of winegrowers. The results provide the local winegrowers with information necessary to understand current processes, as well as historical and future viticulture trends at the scale of their site, thereby facilitating decisions about future response strategies.

First step in the preparation of a soil map of the Protected Designation of Origin Valdepeñas (Central, Spain)

This work is a first step to make a map of vineyard soils. The characterization of the soils of the Protected Designation of Origin (D.P.O.) Valdepeñas will allow to group the studied profiles according to their physico-chemical characteristics and the concentrations of most relevant chemical elements. 90 soil profiles were analysed throughout the territory and the soils were sampled and described according to FAO (2006) and classified according to and Soil Taxonomy (2014). All samples were air dried, sieved and some physico-chemical parameters were determined following standard protocols. Also, major and trace elements were analysed by X-ray fluorescence. The statistically study was made using the SPSS program. Trend maps were made using the ArcGIS program. The studied soils have the following average properties: pH, 8.3; electrical conductivity, 0,20 dS/m (low); clay, 18.8% (medium) and CaCO3, 17.1% (high). In the study for the major elements. The major elements of these soils are Si, followed by Ca and Al, with an average content of 203.7 g/kg, 105.5 g/kg and 74.0 g/kg respectively. On the other hand, 27 trace elements have been studied. Of all of them, it can be highlighted the average values of Ba (361.8 mg/kg), Sr (129.3 mg/kg), Rb (83.4 mg/kg), V (74.2 mg/kg) and Ce (70.6 mg/kg). Ba, V and Ce values are higher and the values of Sr and Rb are lower to those found in the literature. The discriminant analysis shows a percentage of grouping of 91%. The content of chemical elements together with the physico-chemical characteristics allows grouping the soils in 4 group according to their order in the classification to Soil Taxonomy; due to the importance of the Calcisols in Castilla-La Mancha, it has been decided to establish them as their own group even if they do not appear in Soil Taxonomy classification.

Impact of geographical location on the phenolic profile of minority varieties grown in Spain. II: red grapevines

Because terroir and cultivar are drivers of wine quality, is essential to investigate theirs effects on polyphenolic profile before promoting the implantation of a red minority variety in a specific area. This work, included in MINORVIN project, focuses in the polyphenolic profile of 7 red grapevines minority varieties of Vitis vinifera L. (Morate, Sanguina, Santafe, Terriza Tinta Jeromo Tortozona Tinta) and Tempranillo) from six typical viticulture Spanish areas: Aragón (A1), Cataluña (A2), Castilla la Mancha (A3), Castilla –León (A4), Madrid (A5) and Navarra (A6) of 2020 season. Polyphenolic substances were extracted from grapes. 35 compounds were identified and quantified (mg subtance/kg fresh berry) by HPLC and grouped in anthocyanins (ANT) flavanols (FLAVA), flavonols (FLAVO), hydroxycinnamic (AH), benzoic (BA) acids and stilbenes (ST). Antioxidant activity (AA, mmol TE /g fresh berry) was determined by DPPH method. The results were submitted to a two-way ANOVA to investigate the influence of variety, area and their interaction for each polyphenolic family and cluster analysis was used to construct hierarchical dendrograms, searching the natural groupings among the samples. Sanguina (A3) had the most of total polyphenols while Tempranillo (A5) those of ANT. Sanguina (A2) and (A3) reached the highest values of FLAVO, FLAVA and AA. These two last samples had also the maximum of AA. The effect cultivar and area were significant for all polyphenolic families analyzed. A high variability due to variety (>50%) was observed in FLAVA and the maximum value of variability due to growing area was detected in AA (86.41%), ANT and FLAVO (51%); the interaction variety*zone was significant only for ANT, FLAVO, EST and AA. Finally, dendrograms presented five cluster: i) Sanguina (A2); ii) Sanguina (A3); iii) Tempranillo (A5); iv) Tempranillo (A3); Terriza (A3,A5), Morate (A5,A6); v) Santafé (A1,A6); Tortozona tinta (A1,A3,A6); Tinta Jeromo (A3,A4).

Simulating climate change impact on viticultural systems in historical and emergent vineyards

Global climate change affects regional climates and hold implications for wine growing regions worldwide. Although winegrowers are constantly adapting to internal and external factors, it seems relevant to develop tools, which will allow them to better define actual and future agro-climatic potentials. Within this context, we develop a modelling approach, able to simulate the impact of environmental conditions and constraints on vine behaviour and to highlight potential adaptation strategies according to different climate change scenarios. Our modeling approach, named SEVE (Simulating Environmental impacts on Viticultural Ecosystems), provides a generic modeling framework for simulating grapevine growth and berry ripening under different conditions and constraints (slope, aspect, soil type, climate variability…) as well as production strategies and adaptation rules according to climate change scenarios. Each activity is represented by an autonomous agent able to react and adapt its reaction to the variability of environmental constraints. Using this model, we have recently analyzed the evolution of vineyards’ exposure to climatic risks (frost, pathogen risk, heat wave) and the adaptation strategies potentially implemented by the winegrowers. This approach, implemented for two climate change scenarios, has been initiated in France on traditional (Loire Valley) and emerging (Brittany) vineyards. The objective is to identify the time horizons of adaptations and new opportunities in these two regions. Carried out in collaboration with wine growers, this approach aims to better understand the variability of climate change impacts at local scale in the medium and long term.