Bio-Rad VINEO™ Brettanomytest PCR Kit - Manual (Page 3)

1 - INTRODUCTION
Brettanomyces bruxellensis is a type of yeast that is responsible for the
presence of 4-ethyl Phenol and 4-ethylguaiacol in wine-type drinks, fruit
juices and beers that involves significant economic losses. In wines, its
presence is difficult to detect using classic culture methods, which take a
long time and are non-specific.
Rapid, specific and early detection of this yeast in the wine production would,
however, allow the oenologist and the producer to take preventive
measurements and to eliminate it before the appearance of the phenolated
character that is characteristic of changes induced by this yeast. Compared
with the traditional microbiological method, molecular biology provides high
speed, high sensitivity and high specificity detection solutions.
Diagnosis of the presence of this yeast must make it possible to determine at
what risk level the wine is and how this risk develops over time. This risk is
variable according to the contamination level of the wine. Therefore, an
adapted quantification tool is used to determine whether (i) the population is
low and therefore that risk is low or even controlled, (ii) regular monitoring is
required and the wine can be processed, in intermediate or critical quantities
in the event that the wine must be supervised (iii) and finally whether the
population is very high and in the event that the risk of producing volatile
phenols is also high, an immediate and urgent action is required for the wine.
In all cases, regular monitoring is recommended. It is important to monitor
the development Brettanomyces bruxellensis of in the wine.
VINEO™ Brettanomytest PCR Kit is a quantitative test used for specific
detection of Brettanomyces bruxellensis in wines and grape musts in
fermentation using the real-time polymerase chain technique (RT-PCR). A
specific sequence of Brettanomyces bruxellensis is amplified and detected
simultaneously by means of a fluorescent probe. Implementation of this
test is used to obtain a quantitative result less than 3 hours after extracting
the DNA (VINEO™ Extract DNA Kit, 354-8100). The analysis software
adapted to these tests, Opticon Monitor™ or CFX Manager™ Industrial
Diagnostic Edition, make it possible to measure the Brettanomyces
bruxellensis risk in the analysed wine sample by an automatic and
quantitative analysis. An interpretation of the risk level is proposed to the
user in this way. It is linked to the number of CFU.ml-1 (Colony-forming
unit) detected in the wine:
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