Macrowine 2021
IVES 9 IVES Conference Series 9 Monitoring the tawny port wine aging process using precision enology

Monitoring the tawny port wine aging process using precision enology

Abstract

AIM: Tawny Port wine is produced in the Douro Demarcated Region by blending several fortified wines in different aging stages. During the aging process in small wood barrels, the red wine color progressively develops into tawny, medium tawny, or light tawny. In this Port wine style, there are some special categories like Tawny Reserve, Tawny with Indication of Age (10, 20, 30, and 40 years), and “Colheita” that are commercialized worldwide. This last category is an exception, as these wines are from a single vintage [1]. In Tawny Port wine the oxidative aging process is multifactorial and critical for reaching the required quality. So, real-time monitoring of important intrinsic and extrinsic factors known to impact both wine quality and aging time are important to optimize and to manage the natural inconsistency among wines aged in diverse long-used wood barrels. This work shows the design, development, and implementation of a remote distributed system to monitor factors that are identified to be critical for the Tawny Port wine aging process.

METHODS: The Tawny Port wine aging process was monitored in two equal wineries – one of them with controlled temperature– in Vallegre, Porto S.A.. Barrels were instrumented with sensors to measure parameters during the aging process, specifically: pH, redox potential, dissolved oxygen, and temperature. The monitoring process was done using an RS-485 industrial network, which interconnects the mentioned sensors [2].

RESULTS: The distributed monitoring system was capable to detect differences among barrels and among the different storage conditions (controlled and room temperature). Redox potential and dissolved oxygen were the wine’s parameters where the differences among the different barrels were higher under the same storage conditions. Since the Tawny Port wine aging process is oxidative, a variation in the wine’s aging process among barrels is to be expected. Significant differences were detected in the oxygen consumption rate among the different barrels. Differences in the phenolic composition were also observed in the aged wine, both at controlled and room temperature

CONCLUSIONS

Results indicated that the distributed monitoring system was capable to detect variations among barrels and among both storage conditions: controlled and room temperature. Actually, redox potential and dissolved oxygen were the wine’s factors where the variances found were higher among wood barrels, while under the same storage conditions. This methodology is based on easy-to-use implanted systems, with the intention of giving an important contribution to other projects in the area of precision enology

Acknowledgment

The authors want to acknowledge FCT Portugal for funding the CQ – VR through the grant (UIDB/00616/2020 and UIDP/00616/2020), to project INNPORT “Otimização do processo de envelhecimento do vinho do Porto Tawny” and Vallegre Company.

DOI:

Publication date: September 10, 2021

Issue: Macrowine 2021

Type: Article

Contact the author

Keywords

precision enology, wine aging, instrumentation

Citation

Related articles…

The FEM grapevine breeding program: new registered varieties (mid-)resistant to the main ampelopathies

“Vinum debet esse naturale ex genimine vitis et non corruptum”. The Eucharistic wine must be made with pure grapes that must not be contaminated in any way. This is how wine was born in the monastery of the Augustinians, and that is how the genetic improvement of grapevine implemented over the decades at the Agricultural Institute of San Michele all’Adige (since 1874; Trentino – Italy) has been oriented to make the cultivation of grapes always more sustainable. This concept is still current and meets the worldwide urgent need of reducing the use of chemicals, under a climate crisis scenario. Since the beginning of the twentieth century, the varieties introduced in Trentino and the new cultivars produced by pioneer breeders have already embraced the principle of sustainable viticulture.

Influence du terroir sur la composition en flavonoïdes de la baie de raisin de Cabernet franc en Moyenne Vallée de la Loire

The terroir offers great variability in the typicity of the wines produced. Following tastings integrating several vintages, the multiple factor analysis of the sensory data revealed a group of taste criteria contributing to the notion of “Power”, referenced “Power and Harmony”, which makes it possible to differentiate wines from various terroirs of the Middle Loire Valley (Pages et al ., 1987).

The impact of delayed grapevine budbreak on lemberger wine sensory compounds under variable weather conditions

Spring freeze events threaten grape production globally. As grape buds emerge from dormancy in spring, freezing temperatures have the potential to damage green tissues, decreasing yield potential and compromising fruit quality by harvest.

Survey of winegrape irrigation practices in the Sacramento-San Joaquin Valley of California

In California vineyards, irrigation is considered as one of the most important decisions growers will make. Recent research has revealed that decisions of when to begin irrigation and how much water to apply have considerable consequences for final grape quality and hence wine quality. However, it is unclear whether and to what extent the average winegrape grower uses objective data to begin irrigating or to determine the amount of water to apply.

Electrochemical diversity of italian white wines

Analysis of phenolic compounds typically involve spectrophotometric methods as well as liquid chromatography combined with DAD, fluorimetric, or MS detection. However, the complexity of wine phenolic composition generated, in recent years, attention towards other analytical approaches, including those allowing rapid and inexpensive operations. Voltametric AIM Oxidation of white wine phenolics occurs at different stages during winemaking and storage and can have important implications for wine sensory quality. Phenolic compounds, in particular those with a ortho-diphenol moiety, are main target of oxidation in wine. Strategies for the methods are particularly suited for the analysis of oxidizable compounds such as phenolics. The redox-active species can be oxidized and reduced at the electrode, therefore, applications of electrochemistry have been developed both to quantify such species, and to probe wine maturation processes.3 The project on the diversity of Italian wines aims at collecting and analysing large-scale compositional dataset related to Italian white wines.