Process photometry has many applications in breweries. Besides the actual production of beer, for which SIGRIST did pioneering work with precision turbidity measurement for filter monitoring, these include
- treatment of the brewing water
- wastewater treatment
- monitoring phase transitions phase switch
- laboratory checks
Depending on the quality of the available raw water, treatment of the brewing water may employ the same techniques as drinking water treatment: flocculation, sand filtration, ozone sterilization (ozone measurement), activated carbon filtration (activated carbon filter).
In the actual production process, the main application is the measurement of turbidity values for the purpose of monitoring beer filtration. Dual-angle method, i.e. the detection of the scattered light intensity at two different angles, is used to distinguish particle sizes. Other measuring points are used to check wort lautering, yeast dosing, and colour, especially the wort colour.
SIGRIST photometer for detecting phase transitions is used in various applications (water-wort, yeast-beer, and beer-water). Phase switch
A special laboratory version of the SIGRIST turbidimeter is used for measuring individual samples in the measuring cell or in filled beer bottles. It is equipped with an automatic rotation device and an electronic evaluation system for eliminating the effect of any optical irregularities in the bottle glass. Use of a water bath eliminates problems of condensation when measuring cold samples.
Figure 5 is a schematic layout of the beer brewing process with possible measuring points.
Fig. 5: Brewing process
|1||Turbidity after Lauter Tun||15||Turbidity in the Brewery's Laboratory|
|2||Turbidity after Whirlpool||16||Turbidity before Filler|
|3||Phase Separation Water/Wort||17||Colour (EBC) of Hot Wort before Cooler|
|4||Yeast Dosing||19||Turbidity in Trated Water|
|5||Phase Separation Yeast/Beer||21||pH Value in Raw Water / Treated Water|
|6||Turbidity at the Separator|
|7||Turbidity for Kieselguhr Dosing||22||Conductivity in Raw Water / Treated Water|
|8||Turbidity for Beer Filtration Monitoring|
|9||Colour (EBC) after Beer Filtration||23||ORP in Raw Water / Treated Water|
|10||Turbidity for PVPP Dosing|
|11||Turbidity after PVPP Filtration||22||Dissolved Oxygen in Raw Water / Treated Water|
|12||Turbidity after Sheet Filter|
|13||Colour (EBC) of Beer at the Blending Unit||23||Concentration of Free Chlorine, Chlorine dioxide (CIO2) and Ozone (O3) in Water|
|14||Phase Separation Beer/Water|