The production of volatile phenols (4-ethylphénol, 4-ethylguaïacol) by Brettanomyces is a dreaded spoilage. At concentrations of 450 µg/L and higher, the quality and wine typicity are strongly marked by animal notes.
Originating from the grapes, Brettanomyces can develop at any time in the juice [Ae1] and wine if fermentation is not properly managed (hygiene conditions and the use of selected yeasts and bacteria). Indeed, the use of selected microorganisms "closes" the door to indigenous microorganisms and ensures a reduction of the latency period before post-fermentation sulphiting. These spoilage microorganisms may also occur if the stabilization steps (sulphiting and regular monitoring of the free and total SO2, topping up, racking, tank and drum maintenance, etc.) are not properly done.
During the entire winemaking process, microbiological and chemical analytical tools are available to anticipate, prevent and respond to Brettanomyces development.
The requested information and the expected delay are closely related. If an analysis is carried out in order to manage the winemaking process, a quick response is needed. However, if the analysis is being done to confirm the absence of Brettanomyces, it is not necessary to have a rapid response.
Whichever option you choose, even the simplest analysis:
- Must be capable of measuring the kinetics of the population and should therefore not be implemented in isolation.
- Is a tool to decide whether or not the result is properly used.
Culture on selective medium
Real time PCR
|Population of cultivable yeasts: in CFU*/mL
|Population viable yeats :in cells/mL
|Population in equivalent CFU*/mL
*CFU = Colony Forming Unit
Consult the page “volatile phenols” in « Contaminants » section
Our quality guarantee
Genetic test with reference strains