The beer is a fermented alcoholic drink whose basic ingredients are malted barley (germinated barley), water (beer contains 95 % of it), hop and yeasts.

The production of beer is made of three big steps: malting, mashing en fermentation.

These three steps are divided in many operations. We will particularly describe the following ones :

1. Malting 
2. Mashing 
3. Boiling and hopping 
4. Fermentation
5. Maturation and bottling

 2 - Mashing

The goal of mashing is to obtain from the raw materials (water, malt and hop) a sweet and flavoured wort which will then go through an alcohol fermentation.
Mashing includes the three following operations :

• Malt crushing ;
• Mashing ;
• Wort filtration.

During the mashing, the malt that was crushed before is mixed with water. This mixture of water, crushed malt with other various ingredients is the mash.

The mash is heated at accurate temperatures during predetermined laps of time in order to have a complete transformation of the starch from the malt and of the cereals used for sugar: that is the mashing.
This transformation of starch into sugar by the enzymes was lightly initiated during malting. It is essential because yeast can’t transform directly starch into alcohol. Starch has to be first transformed into sugar by the enzymes developed during malting.

Once these transformations into sugar finished, the liquid is filtered to eliminate the husk of the malt grain. The product that is then obtained is the wort; it is a sweet liquid which already has the colour of beer.

The brewer can, by choosing the temperature level, act on the composition of the wort. For maltose is fermentescible and for starch gums aren’t, he can obtain beer that is more or less rich in alcohol. The duration of mashing is more or less two hours. Then the mash is filtered in a filter press. The insoluble materials are the spent grains (25% of the weight of the malt). The wort is pumped into a brew kettle heated by vapour coils.