Improvement of beer brewing by using genetically modified yeast

During fermentation of beer, yeast cells produce ethanol as well as diacetyl, a substance with a low taste threshold of about 0.2 ppm. This unpleasant butter-like flavor can be removed by means of a separate maturation period of 2-6 weeks during which yeast cells degrade the diacetyl. Recombinant DN...

Full description

Saved in:
Bibliographic Details
Main Authors Vogel, J. (Technische Universitat Berlin, Berlin, Germany.), Wackerbauer, K, Stahl, U
Format Book
LanguageEnglish
Published Washington, DC (USA) American Chemical Society 1995
Subjects
BIERE
BRASSAGE
CERVEZAS
GENIE GENETIQUE
INGENIERIA GENETICA
LEVADURA DE CERVEZA
LEVURE DE BIERE
MALTEADO
Online AccessGet more information

Cover

More Information
Summary:During fermentation of beer, yeast cells produce ethanol as well as diacetyl, a substance with a low taste threshold of about 0.2 ppm. This unpleasant butter-like flavor can be removed by means of a separate maturation period of 2-6 weeks during which yeast cells degrade the diacetyl. Recombinant DNA techniques have made it possible to reduce the amount of alpha-acetolactate, the precursor molecule of diacetyl, in yeast. The alpha-acetolactatedecarboxylase (ALDC) gene from Acetobacter pasteurianus, which decarboxylates alpha-acetolactate directly into acetoin without forming diacetyl, was isolated and transferred into brewer's yeast. Test fermentation with recombinant yeast having ALDC activity showed no differences in fermentation properties. At the end of the fermentation process hardly any diacetyl was measurable; thus the subsequent maturation period was unnecessary
Bibliography:Q02
9710944
ISBN:9780841233201
0841233209