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Quantifying Yeast Chronological Life Span by Outgrowth of Aged Cells
Published on: May 6, 2009
Decrease of aged beer aroma by the reducing activity of brewing yeast
Daan Saison1, David P De Schutter, Nele Vanbeneden
1Centre for Malting and Brewing Science, Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering, Katholieke Universiteit Leuven, Kasteelpark Arenberg 22, Box 2463, 3001 Heverlee, Belgium. daan.saison@biw.kuleuven.be
Journal of Agricultural and Food Chemistry
|February 11, 2010
Summary
Brewing yeast significantly impacts beer flavor stability by reducing aged aroma compounds like (E)-2-nonenal. This study demonstrates yeast
Area of Science:
- Food Science
- Microbiology
- Sensory Science
Background:
- Beer flavor profiles change during storage.
- Yeast may influence flavor stability in aged beer.
Purpose of the Study:
- To investigate the direct impact of brewing yeast on aged beer aroma.
- To determine if yeast can mitigate off-flavors developed during beer aging.
Main Methods:
- Refermentation of aged beers with brewing yeast.
- Analysis of aroma compound reduction and formation during refermentation.
Main Results:
- Brewing yeast effectively removed aged aroma notes like cardboard and Madeira.
- Aldehydes, including (E)-2-nonenal, were reduced to alcohols by yeast.
- Yeast exhibited high reducing capacity, though strain-specific residuals remained.
- Aldehyde formation was also observed during refermentation.
Conclusions:
- Brewing yeast plays a crucial role in beer flavor stabilization.
- Yeast's reducing activity can mitigate undesirable aged beer aromas.
- Further research is needed on yeast strain-specific impacts and aldehyde formation during refermentation.
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