The taste and quality of beer largely depend on quality of water used to brew it. Measurements of pH and electrical conductivity determine its quality. Globalization has put enormous competitive pressure on breweries. Maintaining high quality of beer is key to success in market. The use of technology analytics can guarantee beer quality while optimizing process control.

Not just taste, but measurement of pH, conductivity and oxygen content in brewing process

The pH value and salt content of brewing water are main factors that determine taste and quality of beer. This is why raw or drinking water must undergo various treatments, ranging from reverse osmosis and chemical treatment to filtration, depending on what it contains. The pH sensor SE 558 or conductivity sensor SE 605 Memosens are used to control alkalinity of brewing water and required salt level for each type of beer.

1. Saccharification process: Conversion of starch to sugar highly dependent on pH

In downstream process, measurement of pH value also plays an important role. After mixing brewing water with malt, enzymes convert starch it contains into maltose. This highly pH dependent process occurs in pH range of 5.4 to 5.6. Next, boil wort, add hops to control taste and shelf life of future beer, set specific gravity and lower pH. Since pH sensor SE 555 can be sterilized with superheated steam and is biocompatible, it is ideal for monitoring these processes.

2. Oxygen measurement is essential for reliable process control

The hop fragments and precipitated proteins are then separated in a vortex, and a portion of yeast and oxygen is added to wort to start fermentation process. Strict rules apply to yeast. During yeast culture, pH value and dissolved oxygen content of yeast are controlled to ensure optimal yeast activity. Because dissolved oxygen levels determine yeast viability during fermentation and flavor development, oxygen measurement is essential for reliable process control. Therefore, oxygen sensor SE 706 in hygienic stainless steel design guarantees a reliable online measurement.

The wort is then turned into green beer in storage tanks. During this stage, low oxygen level preserves taste of beer. Continuous oxygen measurement also detects leaks in storage tanks in a timely manner. Before bottling, beer is filtered and stored in pressurized tanks. To ensure flavor and prevent oxidation, maximum oxygen concentration must be limited. Some major breweries also set exact alcohol level by diluting beer with degassed water. The degassing process is controlled by measuring content of dissolved oxygen. The same goes for bottling, where oxygen levels must be kept below 25 ppb to maintain shelf life and flavor.

3.CIP: adding flushing medium with inductive conductivity measurement

To comply with strict food hygiene regulations, brewing system must be flushed alternately with sodium hydroxide solution and acid (usually nitric acid) at around 65°C (CIP process). The concentration of CIP medium (intrusion) is monitored based on measurement of inductive conductivity of SE 680 sensor. During last flush of cleaning process line, complete removal of all flushing materials is checked using conductivity sensor SE 605h.

4. Brewery Wastewater Treatment

Finally, Memosens technology is also used in treatment of wastewater from breweries, which requires sensors such as pH sensor SE 554, highly chemically resistant SE 655 sensor for measuring inductive conductance in heavily polluted media, and long-term stable sensor SE. oxygen sensor 715. Since brewery wastewater treatment involves an unusually large amount of waste, it is recommended to install automatic treatment systems at appropriate measuring points.