Brew your own beer - with this step-by-step guide to beer production

A variety of different factors are crucial to producing a good beer. From the colour and the flavour, to the carbon dioxide content and to the height of the head – these are all critical properties that can make all the difference with regard to quality.

In order to influence these properties, it goes without saying that good ingredients such as water, malt, yeast and hops are required. However, the beer production process itself also plays a particularly important role!

During beer production, factors such as temperature, fill level, pH value, pressure and flow rate are crucial. Only when these parameters are precisely monitored and controlled can the production of a high-quality beer be guaranteed.

How can you succesfully produce beer, in ten steps?

Automation24 explains the brewing process to you, and presents the process of beer manufacture in ten steps. Let yourself be carried off to the world of beer and find out what exactly goes on during the brewing process.

Fig. 1: Ten important steps make up the brewing process - Automation24 explains them to you.

1. Step: Grain becomes crushed malt

We'll start right at the very beginning. At the beginning of the process you have sprouted grain, also known as malt. For the majority of beers, wheat and barley form the basis, however, for exclusive beers spelt and rye are also used, for example.

The raw materials required for beer production are stored in raw material silos, which, through the continuous measurement of the fill level e.g. using contactless radar level transmitters, are prevented from running empty.

The reaching of limit values can also be detected using a vibrating level switch, or a rotary paddle switch for bulk solids.

The grain is sprouted, whereby it is soaked in water for a few days and then dried again for a few days. Through the so-called germination process, the enzymes in the grains are activated.

Here, the addition of water can be monitored using electromagnetic flow meters, while temperature sensors, temperature transmitters and temperature controllers are suitable for monitoring the drying process.

Fig. 2: Malted grain forms the basis for beer production

Finally, the malt is ground in a malt mill. Here, various degrees of purity are possible, however, what is important is that the husks remain intact.

In order that the mill is not operated without malt, which runs the risk of causing damage, a continuous supply of malt must be ensured. Hygienic capacitive level switches or vibrating level switches for bulk solids provide a suitable solution in this regard.

Furthermore, in order to monitor the proper function of the malt mill, additional vibration sensors are used, for example.

2. Step: Mashing - malt starch becomes sugar

Finally, the malt grist is blended with water in a vat to form a mixture that is known as "mash". For this reason, the vat is also known as a "mash kettle" and the process itself is called "mashing".

Here, the addition of water is also monitored with electromagnetic flow meters.

In order that the mash kettle always remains full, its fill level must be continually monitored. Radar level transmitters or hydrostatic level transmitters, for example, represent suitable solutions in this regard.

During mashing, enzymes are activated by heating, which split the starches in the malt - into fermentable and non-fermentable sugars.

For this reason, this process step is also known as "sugaring".

The fermentable sugar (maltose) is later converted into alcohol, while the sugar remains in the beer as a sweetener.

Following the rest phases, the mixture is heated to 78°C and is immediately "mashed out", i.e. it is moved on to the next process step.

Adherence to the optimal temperatures during the mashing process can, for example, be guaranteed using hygienic temperature sensors, temperature transmitters, and temperature controllers.

The entire mashing process lasts for around one hour. The result of this process is an aromatic brew consisting of soluble extracts and insoluble solids.

If there are only lighter draff clumps, a second wort can help at this stage.

However, compacted draff with a height of more than 30 cm must first be broken up using an agitator. This ensures that liquid can pass through the sieve, thus guaranteeing an even washout.

A lack of draff, on the other hand, requires the addition of flavour-neutral solids such as rice husks or straw so that the gravitational force of the undissolved malt grist can get to work, and complete filtration will be possible.

Because viscosity decreases with increasing heat, during purification the additional use of suitable tempeature measurement technology is recommended in order to monitor the temperature of the wort and to enable its optimal filtration.

The process of purification ends with the production of the greatest quantity of extracted wort, i.e. upon reaching "kettle-full wort". In order to determine this point in time, the concentration of the wort must be measured.

Fig. 5: The wort is boiled while adding hops

4. Step: Boiling the wort and addition of hops

The residual sugar is removed from the draff with hot water at an optimal temperature of 78°C, that is, the draff is washed, and is then re-used as animal feed or for baking bread. This process is also known in expert circles as "sparging".

On the other hand, the remaining clear liquid or wort is boiled in a "wort kettle", with the hops gradually added in measured quantities.

The supply of wort and hops can be dosed using appropriate level measurement technology, as well as pressure sensors and pressure transmitters with a hygienic connection. This prevents the overflowing of the kettle and guarantees a more reliable boiling process.

When boiling the wort, it is also vitally important that you remain in control of the temperature, for example using temperature sensors, temperature transmitters, and temperature controllers, as boiling kills bacteria and the wort is sterilised and the shelf life is extended.

What's more, this also releases valuable ingredients from the hops, including, for example, essential oils and bitter alpha acids.

In this context, it is therefore important that you monitor the acidity, e.g. using pH sensors. A lower pH value causes the beer to taste sour. On the other hand, a higher value favours a milder flavour.

The hop quantity, variety, and boiling time, on the other hand, determine how bitter the finished beer will taste. Experts distinguish between the bitter content of different beers using the International Bitterness Units scale, or the "IBU" for short.

The evaporation of the water results in what is, for thetime being, the final "original wort content". This measurement value is generally expressed using the unit of measurement 'Degrees Plato" (°P) and describes the proportion of nutrients that have been released from the malt and hops into the water prior to fermentation. The original wort content, for example, can be precisely determined using a wort spindle. If the level of original wort is too high, boiled water can be used to dilute it.

5. Step: Clarification of the wort

In modern breweries, the hopped wort, or "cast wort" is now pumped, generally into a cylindrical vessel with paddles, which is referred to as a "whirlpool".

With suitable level measurement technology it can be ensured, for example, that ideal quantities of wort are transferred, and the vessel does not overflow. To ensure that the whirlpool does not run dry, hygienic point level sensors with hygienic process connections can be used.

With the help of the rotating paddle, suspended particles produced during boiling, such as protein flakes (spent hops) and solid particles (fraction) in the form of hops and fibre particles in the middle of the vessel. The unwanted residues are then suctioned off with a pump after around half an hour.

Fig. 6: Modern brewery equipment

Fig 9: The correct storage of the beer has an influence on the aroma and the flavour

8. Step: Beer storage

To allow the beer to unfold its full aroma and develop its typical colour, it is recommended that it be stored in a tank for up to three weeks. The temperature should be between 1°C and 2°C. During this secondary fermentation period, the last insoluble residual substances settle.

By measuring and monitoring pressure, temperature, and CO₂-content, the brewer can determine the optimal beer maturity time.

Pressure sensors and pressure transmitters for hygiene applications are available for pressure and CO₂ monitoring. Temperature measurement can be performed e.g. using temperature measurement technology that is suitable for the food industry.

9. Step: Final filtration

In order to produce a clear beer with an appealing colour, the final residues such as hops, yeast and mixtures of proteins and tannic substances are filtered from the secondary fermentation process, e.g. using a "diatomite filter".

The minimum and maximum limit levels of the feed tank for diatomaceous earth are detected with capacitive level switches for hygienic applications.

Within the filtration system itself, the flow of liquid can be monitored using flow sensors.

The level of contamination of the filter can be monitored using pressure sensors or pressure transmitters for the food industry. In this way, filter blockages can be avoided.

Fig. 10: A final filtration guarantees the purity of the beer

Fig. 11: When bottling, care must be taken to ensure that no carbon dioxide escapes

10. Step: Bottling & CIP/SIP cleaning

The last main step in the beer production process is the filling of the beer into bottles, cans, or barrels.

Here it comes down to ensuring the correct counter-pressure so as to prevent an escape of carbon dioxide. Both pressure sensors and pressure transmitters help keep the pressure under control.

The waste tank can be prevented from running dry using hygienic capacitive level switches. With the level sensors suitable for the food industry, the quantities of beer in the tanks is monitored.

Because the use of automation technology for the food industry always requires special hygiene precautions, the careful cleaning of all systems must be performed following the brewing process. Here, automated CIP/SIP processes ensure, for example, that beer brewing always remains a safe and germ-free process.

Using conductivity sensors you can in turn ensure that no cleaning agents or rinsing water residues make their way into the production circuit, and consequently into the beer.