Macrowine 2021
IVES 9 IVES Conference Series 9 Efficiency of alternative chemical and physical treatments in reducing Brettanomyces Bruxellensis from oak wood

Efficiency of alternative chemical and physical treatments in reducing Brettanomyces Bruxellensis from oak wood

Abstract

Oak barrels form an integral part of wine production, especially that of high quality wines. However, due to its porosity, wood presents an ecological niche for microbial proliferation and is highly susceptible to microbial spoilage which could cause considerable economic losses. Brettanomyces bruxellensis, the most commonly encountered microorganism responsible for spoilage during barrel ageing, can remain in barrels after barrel sanitation to contaminate new batches of wine after refilling. Therefore, effective sanitation treatments are of utmost importance to prevent recurring wine spoilage. Since a moratorium on the use of sulphur dioxide, the most widely used biocide for barrel sanitation, has been issued by the European Commission, there is a drastic need to evaluate alternative sanitation methods. Literature on the effectiveness of barrel sanitation treatments is scattered and presents inconclusive results. Furthermore, all studies have used culture-dependent methods to detect Brettanomyces which has been reported to attain a viable but non-culturable state [1,2]. Therefore, the aim of this study was to evaluate several physical and chemical sanitation treatments in their efficiency to eliminate B. bruxellensis from oak wood. French oak wood was contaminated with different B. bruxellensis strains and subsequently subjected to several chemical and physical sanitation treatments. The methods included, among others, ozone gas, ozonated water, high pressure ultrasound, steam, peracetic acid, sodium percarbonate and microwave. After their extraction from the oak wood, Brettanomyces cells were subjected to a fluorescence-based live/dead staining and detected by means of flow cytometry. The treatments differed greatly in their ability to reduce B. bruxellensis cells with ozone gas showing promising results. Sodium percarbonate and steam treatments were also effective in reducing cells. This study presents the first evaluation of alternative barrel sanitation treatments by flow cytometry, a culture-independent method, and is also the first study to compare an array of barrel sanitation treatments under controlled conditions.

1. Agnolucci, M., Rea, F., Sbrana, C., Cristani, C., Fracassetti, D., Tirelli, A., Nuti, M., 2010. Sulphur dioxide affects culturability and volatile phenol production by Brettanomyces/ Dekkera bruxellensis. International Journal of Food Microbiology 143, 76-80. 2. Serpaggi, V., Remize, F., Recorbet, G., Gaudot-Dumas, E., Sequeira-Le Grand, A., Alexandre, H., 2012. Characterization of the “viable but nonculturable”(VBNC) state in the wine spoilage yeast Brettanomyces. Food Microbiology 30, 438-447.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Article

Authors

Engela Kritzinger*, Maren Scharfenberger-Schm, Ulrich Fischer

*DLR Rheinpfalz

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

The influence of soil management practices on functional traits and biodiversity of weed communities in Swiss vineyards

Green cover in vine rows provides many ecological services, but can also negatively impact the crop, depending on the weed species. The composition of a vineyard weed community is influenced by many parameters. Ensuring an evolution of the vine row flora into a desired direction is therefore very complex. A key step towards this goal is to know which factors influence the establishment of the weed community and which types of communities are best suited for vineyards. In this study, we analysed the weed communities of several vineyards in the Lake Geneva region (379 botanical surveys on 117 plots), with the aim to highlight the links between soil management practices (chemical and mechanical weeding, mowing, mulching roll) and phytosociological profiles, biodiversity and selected functional traits (growth forms, life strategies, root depth). T

Reduction of herbaceous aromas by wine lactic acid bacteria mediated degradation of volatile aldehydes

Consumers typically prefer wines with floral and fruity aromas over those presenting green-pepper, vegetal or herbaceous notes. Pyrazines have been identified as causatives for herbaceous notes in wines, especially Bordeaux reds. However, pyrazines are not universally responsible for herbaceousness, and several other wine volatile compounds are known to produce distinct vegetal/herbaceous aromas in wines. Specifically, volatile aldehydes elicit sensations of herbaceousness or grassiness and have been described in wines well above their perception thresholds.

A preliminary study of clonal selection in cv. Viura in relation to varietal aroma profile

Viura is a synonym for Macabeo and currently it is the most widely planted white grape variety in D.O.Ca. Rioja, with 3,569 ha, representing 84% of the white grape cultivated area. It is a generous-yielding grape, presenting low values of titratable acidity and with large and compact clusters which makes it susceptible to Botrytis cinerea. Thus, this variety not always satisfies the wine grower’s prospects. Nowadays, the available plant material is scarce, moreover, it was selected on the basis of other quality criteria, not currently requested.

Capture depletion of grapevine DNA: an approach to advance the study of microbial community in wine

The use of next-generation sequencing (NGS) has helped understand microbial genetics in oenology. Current studies mainly focus on barcoded amplicon NGS but not shotgun sequencing, which is useful for functional analyses. Since the high percentage of grapevine DNA conceals the microbial DNA in must, the majority of sequencing data is wasted in bioinformatic analyses. Here we present capture depletion of grapevine whole genome DNA.

Anthocyanin accumulation and extractability during the maturation of the grapes of three varieties

Anthocyanin accumulation and extractability were studied in Tannat, Cabernet Sauvignon and Merlot grapes produced in the south of Uruguay in two consecutive seasons. Typical cultivation situations employed in the region for each variety were considered. A follow-up was carried out, considering 60 plants per vineyard, and the harvest was determined according to the technological indices of maturity. Samples of grapes were taken in duplicate in each vineyard periodically along grape maturation. The basic composition, polyphenolic potential and anthocyanin extractability were determined. Also, half of grapes were frozen and later peeled; skin extractions over 24 hs with a solution of 12% ethanol and pH 3.2 were carried out. The anthocyanin contents of the extracts obtained were determined by HPLC-DAD. The levels of anthocyanins reached the highest values before technological maturity. Anthocyanin extractability had a decrease during grape maturation.