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…

Novel contribution to the study of mouth-feel properties in wines

In general, there is a well-established lexicon related to wine aroma and taste properties; however mouth-feel-related vocabulary usually includes heterogeneous, multimodal and personalized terms. Gawel et al.
(2000) published a wheel related to mouthfeel properties of red wine. However, its use in scientific publications has been limited. The authors accepted that the approach had certain limitations as it included redundant and terms with hedonic tone and some others were absent. It is of high interest to generate a mouth-feel lexicon and finding the chemical compound or group of compounds responsible for such properties in red wine. In the present work a chemical fractionation method has been developed.

Comparative proteomic analysis of wines made from Botrytis cinerea infected and healthy grapes reveal interesting parallels to the gushing phenomenon in sparkling wine

In addition to aroma compounds also protein composition strongly influences the quality of wines. Proteins of wine derive mainly from the plant Vitis vinifera and may be influenced by abiotic stress as well as fermentation conditions or fining. Additionally, fungal infections can affect the protein content as well by introducing fungal proteins or affecting grape protein composition. An infection of the vine with the plant pathogenic fungus Botrytis (B.) cinerea was shown to cause a degradation of proteins in the resulting wine. Moreover, it influences the foaming properties in sparkling wine.

The role of tomato juice serum in malolactic fermentation in wine

Introduction: Malolactic fermentation (MLF) is a common process in winemaking to reduce wine acidity, maintain microbial stability and modify wine aroma. However, successful MLF is often hampered by their sluggish or stuck activity of malolactic bacteria (MLB) which may be caused by nutrient deficiency, especially when MLB are inoculated after alcoholic fermentation (Alexandre et al., 2004; Lerm et al., 2010). Identification and characterization of essential nutrients and growth factors for MLB allows for production of highly efficient nutrient supplements for MLF.

Towards multi-purpose valorisation of polyphenols from grape pomace: Pressurized liquid extraction coupled to purification by membrane processes

Grape by-products (including skins, seeds, stems and vine shoots) are rich in health promoting polyphenols. Their extraction from winery waste and their following purification are of special interest to produce extracts with high added value compounds. Meanwhile, the growing concern over environmental problems associated with economic constraints, require the development of environmentally sustainable extraction technologies. The extraction using semi-continuous subcritical water, as a natural solvent at high temperature and high pressure a technology is promising “green” technology that is environmentally friendly, energy efficient and improve the extraction process in plant tissues.

Impact of some agronomic practices on grape skins anthocyanin content

Wine colour is the first quality characteristic to be assessed, especially regarding red wines. Anthocyanins are very well known to be the main responsible compounds for red wine colour. Red cultivars can synthesize and accumulate anthocyanins in berry skin to express their colour. However, anthocyanin accumulation is often influenced by a series of factors, such as genetic regulation, phytohormones, environmental conditions and viticultural management.