Roll out the barrel and spot the poison
A Flir Systems infrared camera watches over the bottling of the world-famous Erdinger wheat beer in Germany.
Erdinger Weissbräu is one of the country’s largest and most successful private breweries. The Munich-based brewery exports its specialty beers to more than 70 countries. Erdinger brews its beers only in its plant in Erding, six days a week around the clock, and without ever deviating from its standard process.
Erdinger is known for its strict quality policy and its consistent brand awareness. Its production processes, from selection and acceptance of raw materials to filling and maturing, are strictly monitored. Consequently, Erdinger Weissbräu maintains a permanent chain of security controls for its keg filling and packing process.
However, simulation and risk analysis have shown that no matter how careful the production, it was conceivable that customers could take delivery of a keg filled with lye – a caustic chemical used in the cleaning process that is poisonous and corrosive.
In order to prevent accidents of this kind, HACCP, a quality assurance program for the German food industry, stipulates the installation of critical control points.
Erdinger Weissbräu decided to ensure a 100 per cent protection of its keg cleaning and filling process. Risk analysis demonstrated the need to set up an additional control point to ensure that a keg filled with lye could not slip through the conventional control points.
As a keg containing lye has a considerably higher temperature than one filled with beer, continuous monitoring of temperatures proved to be the optimum solution. In this way, it was easy to identify wrongly filled kegs by measuring the temperature of each.
Non-contact temperature measurement using spot pyrometer thermometers proved not to be sufficiently reliable for this application. Accordingly, an infrared camera was the chosen option. When correctly adjusted and interpreted, the camera’s images enable a virtually errorfree measurement.
A Flir Systems A-Series thermal imaging camera now measures the temperature of every keg before it leaves the conveyor belt of the filling installation. If the infrared camera identifies a keg with a different temperature, it sets off an alarm and the conveyor belt is automatically halted. The keg is then manually removed.
The monitoring system with the infrared camera at the Erdinger brewery has proven to be extremely successful. The system is regularly inspected, but even in error simulations the camera has proven itself particularly reliable – any deviation has been identified immediately, triggering the appropriate alarm stage.
“Not one keg filled with lye has left the filling shed,” says a spokesman for Erdinger Weissbräu.
Through software, Erdinger’s camera is connected to a touch screen monitor that shows which size and type of keg is going through the cleaning and filling process. A thermal image of each keg is simultaneously shown on the monitor screen in real time. The system is not incorporated into the washing and filling machinery, which means it can be used on any filling installations.
The infrared image above shows a keg filled with beer is cooler than the keg (below) filled with the poisonous cleaning fluid lye.