IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Analysis of mousy off-flavour wines

Analysis of mousy off-flavour wines

Abstract

Winemakers are increasingly experimenting with new techniques, such as spontaneous fermentation, prolonged yeast contact, higher pH, minimal sulphur dioxid, filtration and clarification or oxidative ageing. Along with this, the risk of microbial spoilage increases, and so the off-flavour mousiness, long time underestimated, is becoming more frequent. Characteristic of the mousy off-flavour is the delayed perception after swallowing the wine. After a few seconds the flavour appears, reminiscent of a dirty mouse cage. There are three known compounds that cause mousy off-flavor: 2-ethyltetrahydropyridine, 2-acetyltetrahydopyridine, and 2-acetylpyrroline. Yeasts such as Dekkera/Brettanomyces and heterofermentative lactic acid bacteria like Lactobacillus hilgardii can release these compounds.

This study focuses on the analysis of mousy wines. This includes the quantitative analysis of mousy off-flavour compounds in wine using liquid chromatography with mass spectrometry (HPLC-MS). In order to identify the microorganisms in mousy wines, a next-generation sequencing analysis was carried out. Based on these results, a qPCR method will be developed to quantify the corresponding microorganisms in wine. 

DOI:

Publication date: June 27, 2022

Issue: IVAS 2022

Type: Poster

Authors

Dietzel Caroline1, Wegmann-Herr Pascal1 and Scharfenberger-Schmeer Maren2

1Institute for Viticulture and Enology (DLR-Rheinpfalz)
2University of Applied Sciences, Kaiserslautern

Contact the author

Keywords

Mousy off-flavour, Wine fault, qPCR, Next-Generation-Sequenzing, LC-MS

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Spatial variability of the nutrient distribution in Jerez vineyard soils (Spain)

From a fertility standpoint, the vine has to extract from the soil mineral substances necessary for its existence. However, the amount of certain available nutrients does not always correspond to a proportional increase in quality.

The characteristics of strong territorial brands: the case of Champagne

While most brands belong to individual enterprises, some brands belong to groups of enterprises based in a single territory. This conceptual paper examines the characteristics

Barrels ad-hoc: Spanish oak wood classification by NIRs 

The wooden barrel is a key factor in enology, since wine chemical composition and sensory properties changes significantly in contact with the barrel[1]. Today’s highly competitive market constantly demands new differentiated products and wineries search innovations continuously.
Wood selection is crucial: barrels stability to keep constant their contribution and the result on products, and additional and differentiated wood contributions to impact their new products. Oak wood selection has traditionally been carried out using parameters such as specie, location and grain, however, it goes one step further nowadays. Large cooperage work with non-destructive techniques that allow classifying oak wood quickly and easily according to their organoleptic contribution[2].

‘Cabernet Sauvignon’ (Vitis vinifera L.) berry skin flavonol and anthocyanin composition is affected by trellis systems and applied water amounts

Trellis systems are selected in wine grape vineyards to mainly maximize vineyard yield and maintain berry quality. This study was conducted in 2020 and 2021 to evaluate six commonly utilized trellis systems including a vertical shoot positioning (VSP), two relaxed VSPs (VSP60 and VSP80), a single high wire (SH), a high quadrilateral (HQ), and a guyot (GY), combined with three levels of irrigation regimes based on different crop evapotranspiration (ETc) replacements, including a 25% ETc, 50% ETc, and 100% ETc. The results indicated SH yielded the most fruits and accumulated the most total soluble solids (TSS) at harvest in 2020, however, it showed the lowest TSS in the second season. In 2020, SH and HQ showed higher concentrations in most of the anthocyanin derivatives compared to the VSPs. Similar comparisons were noticed in 2021 as well. SH and HQ also accumulated more flavonols in both years compared to other trellis systems. Overall, this study provides information on the efficacy of trellis systems on grapevine yield and berry flavonoid accumulation in a currently warming climate.

Adaptation to climate change by determining grapevine cultivar differences using temperature-based phenology models

Grapevine phenology is advancing with increased temperatures associated with climate change. This may result in higher fruit sugar concentrations at harvest and/or earlier compressed harvests and changes in the synchrony of sugar with other fruit metabolites. One adaptation strategy that growers may use to maintain typicity of wine style is to change cultivars. This approach may enable fruit