Enzymes in the Beer Brewing Process

Sofia Ramirez-Ekner, Stephanie Berntsen Croft & Marie Juliane Svea Bidstrup

Studenteropgave: Basisprojekt

Abstrakt

Brewing beer with barley grains involves the initiation of a controlled germination for the synthesis of
enzymes in order for the degradation of starch. With many encompassing steps involved, brewers use controlled
methods throughout to provide each enzyme with their optimal environment to achieve highest enzymatic
activity. The natural barley grain enzymes are manipulated in the malting and mashing steps to produce
a quality wort with the desired amount of fermentable sugars, relating to the style of beer being produced.
To link the importance of providing optimal conditions for enzymes that catalyze the hydrolysis of starch, as
they have a direct effect on the characteristics of wort, an experiment was conducted which included colorimetric
enzymatic activity assays. The investigated enzyme was α-amylase EC 3.2.1.1 derived from Bacillus
licheniformis, which was used as amodel for the α-amylase in barley grain with potato starch as substrate. To
understand the parameters affecting starch hydrolysis in beer brewing, enzymatic activity was tested within
a pH range (2.2, 3, 4, 5, 6, 7, 8) and temperature range (25°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C) to
find the optimal conditions. The activity of α-amylase was investigated based on the release of reducing sugar
ends using the 4-Hydroxybenzoylhydrazine (PAHBAH) method. Enzyme activity is expressed in the amount of
reducing sugar ends in mM being produced per minute which was used to find the specific reaction rates of
each individual enzymatic reaction. The optimal conditions found were to be between pH 7 and 8 where the
highest specific reaction rate was 12.32 min-1 and 12.24 min-1, respectively. In the temperature assay, the
optimal temperature was found to be at 60°C where the highest specific reaction rate was 20.62min-1.

UddannelserBasis - Naturvidenskabelig Bacheloruddannelse, (Bachelor uddannelse) Basis
SprogEngelsk
Udgivelsesdato5 dec. 2018
Antal sider37
VejledereBartlomiej Kolaczkowski