Macrowine 2021
IVES 9 IVES Conference Series 9 What do we know about the kerosene/petrol aroma in riesling wines?

What do we know about the kerosene/petrol aroma in riesling wines?

Abstract

AIM: 1,1,6-Trimethyl-1,2-dihydronaphthalene (TDN) is a controversial aroma component found in Riesling wines. It belongs to the family of C13-norisoprenoids and is mainly associated with kerosene/petrol notes. TDN can add complexity to the wine aroma at medium – low concentrations and deteriorate the wine bouquet when its content is high. No TDN aromas are usually perceived in young Riesling wines, but they can appear after several years of aging due to the gradual formation of TDN. Management of TDN in Riesling wines is an actual task, since global warming can promote formation of this compound and compromise the aromatic composition of wine. Therefore, the aim of the current work was, firstly, to study the sensory particularities of TDN in Riesling wine at various concentrations. Secondly, to investigate the ability of bottle closures to absorb (scalp) TDN from Riesling wine under various storage conditions. These studies also include the comparative assessment of our findings with previously published data.

METHODS: sensory analysis, GC-MS (SBSE), HPLC,1H-NMR and other methods related to the synthesis and determination of TDN.

RESULTS: First of all, the method of the synthesis of highly purified TDN (95% and 99.5%) was optimized [1]. The obtained TDN was used for the calibrations in GC-MS analysis and for the sensory and TDN scalping studies. As a result, three sensory thresholds for TDN in Riesling wine were determined: detection threshold (about 4 μg/L), recognition threshold (about 10-12 μg/L) and rejection threshold (about 71-82 μg/L) [2]. It was also demonstrated, that the TDN aroma recognition was easier in the cooled wine. The defined thresholds were discussed in relation to the previously reported sensory thresholds determined by other panels and in other wine matrices. In the experiment of TDN scalping, five bottle closures were studied under storage conditions which varied by ambient temperature (14 °C vs 27 °C) and bottle position (horizontal vs vertical) [3]. A large difference in TDN scalping rate was observed for synthetic and glass stoppers depending on the storage conditions. For example, the TDN absorbance from the wine was more than three times faster by synthetic stoppers at the lower storage temperature compared to the higher one (vertical bottle position). Cork stoppers demonstrated a fast scalping process in all storage scenarios, absorbing up to 40% TDN. In the wine bottled with BVS screw caps, only a minor decrease of TDN was found in all storage variants.

CONCLUSIONS:

TDN is an aroma compound that requires effective control tools in Riesling wines. The described results of the sensory analysis can be used as a reference for the desired content of TDN in finished Riesling wines. At the same time, the outcomes of the TDN scalping study provide a deeper understanding of the impact of bottle closures and storage conditions on the TDN content in wine.

DOI:

Publication date: September 22, 2021

Issue: Macrowine 2021

Type: Article

Authors

Andrii Tarasov, Nicoló Giuliani (1), Alexey Dobrydnev (2), Christoph Schuessler (1), Nikolaus Müller, Yulian Volovenko (2), Doris Rauhut (1), Rainer Jung (1) 

(1) Hochschule Geisenheim University (Germany) (2) Faculty of Chemistry, Taras Shevchenko National University of Kyiv (Ukraine)

Contact the author

Keywords

1,1,6-trimethyl-1,2-dihydronaphthalene (tdn); sensory threshold; scalping; bottle closure; wine

Citation

Related articles…

Decline of new vineyards in Southern Spain

In-season vineyard pest management relies on proper timing, selection, and application of products. Most of the research on pest management tends to focus on the influence of regional conditions on these aspects, with an emphasis on product timing and efficacy evaluation. One aspect that is not fully vetted in various vineyard regions is application (sprayer) technology. The purpose of this study was to determine the influence of regional conditions on sprayer performance in commercial wine grape vineyards in eastern Washington.

Unraveling the role of grape cell wall in shaping the fermentation rate, the polyphenolic profile and quality of red wines from disease-resistant and drought-tolerant grapes in Occitanie varietal selection

Climate change and an evolving environmental and societal context call for the exploration of disease-resistant and/or drought-adapted grape varieties that meet the demands of consumers and society.

New disease-resistant grapevine varieties response to drought under a semi-arid climate

In many regions, climate change leads to an increase in air temperature combined with a reduction of rainfall, intensifying climatic demand and water deficits (WD) (Cardell et al. 2019), which in turn may negatively impact grapevine development, yield and grape composition (Santos et al. 2020). In addition, climate change may also increase disease pressure, leading to further yield and quality losses, besides increasing costs due to increased vineyard spraying (Santos et al. 2020) and reducing viticulture acceptability by consumers (Guichard et al. 2017). Adopting new resistant varieties appears as a promising long-term solution to better manage vine protection, but unfortunately little is known regarding their behavior in front of WD.

Kinetic investigations of the sulfite addition on flavanols

Sulfonated monomeric and dimeric flavan-3-ols are recently discovered in wine and proved to have great importance in understanding wine chemistry and quality [1, 2].

Elucidating white wines peptides: An analytical breaktrough

The chemistry of wine is particularly complex due to biochemical and chemical interactions that significantly modify its organoleptic characteristics and stability over time. Aging on lees is a well-known practice during which various compounds are released, ensuring wines oxidative stability and its overall sensory quality [1,2].