A method for estimating Dekkera/Brettanomyces populations in wines.
OBJECTIVE
The formation of ethylphenols in wines, a consequence of Dekkera/Brettanomyces metabolism, can affect their quality. The main aims of this work were to further our knowledge of Dekkera/Brettanomyces with respect to ethylphenol production, and to develop a methodology for detecting this spoilage yeast and for estimating its population size in wines using differential-selective media and high performance liquid chromatography (HPLC).


RESULTS
This work examines the reduction of p-coumaric acid and the formation of 4-vinylphenol and 4-ethylphenol (recorded by HPLC-DAD) in a prepared medium because of the activities of different yeast species and populations. A regression model was constructed for estimating the population of Dekkera/Brettanomyces at the beginning of fermentation via the conversion of hydroxycinnamic acids into ethylphenols.


CONCLUSIONS
The proposed methodology allows the populations of Dekkera/Brettanomyces at the beginning of fermentation to be estimated in problem wines. Moreover, it avoids false positives because of yeasts resistant to the effects of the selective elements of the medium.


CONCLUSIONS
This may help prevent the appearance of organoleptic anomalies in wines at the winery level.
Benito
S
S
Dept. Tecnología de Alimentos, E.T.S.I. Agrónomos, UPM, Madrid, Spain.
Palomero
F
F
Morata
A
A
Calderón
F
F
Suárez-Lepe
J A
JA
D019342:Acetic Acid / Q000378:metabolism; D055168:Brettanomyces / Q000302:isolation & purification / Q000502:physiology*; D003373:Coumaric Acids / Q000737:chemistry / Q000378:metabolism; D055167:Dekkera / Q000302:isolation & purification / Q000502:physiology*; D005516:Food Microbiology; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry / Q000378:metabolism; D011422:Propionates; D012044:Regression Analysis; D013997:Time Factors; D014920:Wine / Q000382:microbiology*
D003373:Coumaric Acids; D010636:Phenols; D011422:Propionates; C042291:4-ethylphenol; C495469:p-coumaric acid; C030626:4-vinylphenol; D019342:Acetic Acid