Enzyme in Beer Manufacturing - Beer is an undistilled alcoholic bewerage produced from fermentation of barley malt by yeast, especial1y S. cerevisiae or S. carisbergensis. Generally, other materials rich in starch, e.g., wheat, maize, rice, etc., are also added to increase the amount of fermentable sugars and to reduce the relative costs of fermentation; these are called adjuncts.

Barley malt is prepared by soaking the grains in water, allowing them to germinate at 17°C, and then drying them at 65°C once the appropriate stage of germination is reached. For beer preparation the malt is powdered, mixed with warm water at 70°C and pH 5.0; this is called mashing.

Generally, the enzyme activities needed for saccharification (of adjuncts also) before fermentation are provided by the malt. Ordinarily, saccharification is stopped by boiling the wort when about 75% of the starch has been converted into fermentable sugars. The following enzymes are employed in beer production to achieve specific objectives.
1. α-Amylases and β-glucanase are used for increased and rapid saccharification.
2. Neutral proteases are added to the wort to hydrolyse proteins and to increase the fermentation rate .in the later stages.
3. Cellulases are used to digest barley glucans, particularly when wheat is used as an adjunct.
4. Papain is added to the beer during the later post-fermentation stages to hydrolyse the proteins and prevent the occurrence of 'chillhaze'.
5. Glucoamylase and/or fungal α-amylase are used during fermentation to produce low calorie or 'light' beers.