Vinhos de talha: to pitch or not to pitch

Abstract

In Alentejo, south of Portugal there is a traditional way of fermenting wines in clay vessels, known as “Vinhos de Talha”. Clay vessels were traditionally impermeabilized using pine pitch, creating a barrier between the fermenting must and the clay. Due to this unusual production technology that uses of clay vessels, instead of inox or wood vessels, “Vinhos de Talha” present unique characteristics increasingly appreciated by national and international consumers when compared with wine obtained by the said traditional methods of winemaking. Although the positive consumers feedback, there is little literature about the physical-chemical characteristics of these wines (Martins et al, 2018; Cabrita et al, 2018). This work aims to characterize the volatile composition of white wines produced in clay vessels with different coatings and to contribute to the knowledge and preservation of these wines that are a unique cultural heritage. Wine samples were produced during 2019 vintage from white grapes, using the traditional technology associated to these wines. The clay vessels used have different coatings: epoxy resin, bee wax, new pitch, old pitch and no coating. Wines were analyzed after the opening of the vessels in November. Oenological parameters as alcohol, pH, total and volatile acidity, sulphur dioxide, and reducing sugars were measured according to OIV (OIV, 2014) The volatile composition was analyzed by headspace solid phase microextraction hyphenated with gas chromatography / mass spectrometry (HS-SPME-GC/MS), following a methodology based on Martins et al (2018). A linear discriminant analysis was performed using IBM SPSS Statistics 20, and as it is a supervised technique where there is the need to assign groups of variables to the data set, we considered the volatile compounds in wines (independent variables), to classify different types of wines (grouping variable), according to the vessel coating. LDA shows that wines can be discriminated according to different clay vessels impermeabilization materials, being the most similar the ones from clay vessels with no coating and the ones from clay vessels with old pitch.

DOI:

Publication date: September 15, 2021

Issue: Macrowine 2021

Type: Article

Authors

Maria João Cabrita

MED – Mediterranean Institute for Agriculture, Environment and Development, Escola de Ciências e Tecnologia, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal.,Raquel GARCIA MED – Mediterranean Institute for Agriculture, Environment and Development, Departamento de Fitotecnia, Escola de Ciências e Tecnologia, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal. Flávia FREITAS; Marco Gomes da SILVA LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.

Contact the author

Keywords

vinhos de talha; volatile profiling; hs-spme; gc/ms

Citation

Related articles…

Coping with extreme climatic events: some lessons from recent work on grapevine under heat peak

Climate change critically challenges viticulture. Among other threats, extreme and increasingly frequent heatwaves cause irreversible burns on leaves and bunches. A series of observations and experiments was conducted to better understand how leaf burns originate and whether genetics or management practices can mitigate them. In 2019, a panel of 279 potted cultivars of Vitis vinifera L. grown outdoors suffered a heat peak and a genetic origin of leaf burn variability was demonstrated. To deeper explore this variability, fourteen cultivars were selected for their contrasting responses to high temperatures, and detached leaves were submitted to a controlled increase in temperature up to 50 °C in a growth chamber.

Oenological performances of new white grape varieties

The wine industry works to minimize pesticides and adapt to climate change. Breeding programs have developed disease-resistant grape varieties, particularly against downy and powdery mildew, to minimize pesticide applications [1]. However, their enological potential remains underexplored.

EFFECTS OF BIODYNAMIC VINEYARD MANAGEMENT ON GRAPE RIPENING MECHANISMS

Biodynamic agriculture, founded in 1924 by Rudolph Steiner, is a form of organic agriculture. Through a holistic approach, biodynamic agriculture seeks to preserve the diversity of agriculture and the existing interactions between the mineral world and the different components of the organic world. Biodynamic grape production involves the use of composts, herbal teas and mineral preparations such as 500, 501 and CBMT.
Several scientific studies have provided evidence on the effects of biodynamic farming on the soil, the plant and the wine. Numerous empirical opinions of wine growers support the existence of differences brought by such a management.

Chitosan elicits mono-glucosylated stilbene production and release in fed-batch fermentation of grape cells 

In the present study, the optimal conditions of grape (Vitis vinifera cv ‘Barbera’) cell cultures in batch and fed-batch bioreactor processes were studied to specifically improve the production of mono-glucosylated stilbenes.

Novel protocols for variable rate vineyard management

The advent of precision viticulture (PV) has allowed to address problems related to spatial and temporal variability at the within-field scale. Nowadays, several remote and proximal sensing solutions allow description of the existing variability at different temporal and ground resolution through extremely robust soil, vigor, yield, and grape quality maps. In parallel, numerous studies have described grapevine performances within the homogeneous zones and identified soil as main driver of variability. There is a broad consensus that different vigor zones within the same plot may show differential canopy growth, yield and fruit composition, depicting diverse enological potentials and cultural needs.