Dept. Tecnología de Alimentos, E.T.S.I. Agrónomos, UPM, Madrid, Spain.
J Appl Microbiol. 2009 May;106(5):1743-51. doi: 10.1111/j.1365-2672.2008.04137.x. Epub 2009 Feb 16.
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).
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.
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.
This may help prevent the appearance of organoleptic anomalies in wines at the winery level.
葡萄酒中乙基苯酚的形成是德克酵母/贝酵母代谢的结果，会影响其质量。本研究的主要目的是进一步了解德克酵母/贝酵母在乙基苯酚生产方面的情况，并开发一种使用差示选择性培养基和高效液相色谱（HPLC）检测这种葡萄酒污染酵母并估计其在葡萄酒中种群数量的方法。
本研究考察了由于不同酵母种类和数量的作用，在预备培养基中对 p-香豆酸的还原和 4-乙烯基苯酚和 4-乙基苯酚的形成（通过 HPLC-DAD 记录）。通过羟基肉桂酸转化为乙基苯酚，构建了一个用于估计发酵开始时德克酵母/贝酵母种群的回归模型。
所提出的方法可以估计发酵开始时问题葡萄酒中德克酵母/贝酵母的种群数量。此外，它避免了由于对培养基选择性成分有抗性的酵母而产生的假阳性。
这有助于在酿酒厂层面防止葡萄酒出现感官异常。
