Researchers simplify beverage quality control analysis


The Fraunhofer Institute has developed a new method for investigating beer and other beverages for infection by pathogens.

In collaboration with the company GEN-IAL from Troisdorf, researchers at the Fraunhofer Institute for Applied Polymer Research IAP in Potsdam have developed a polymer powder that significantly simplifies quality control tests and shortens the time that they require.

With a new polymer powder, monitoring the production process for quality will be able to be faster and simpler in the future.

Manufacturers can also test drinks such as milk, juice, cola and red wine with the quick check.

Until recently, beer has been filtered in special equipment, where the bacteria remain on a membrane and is cultivated in a special culture medium before they can be examined microscopically. The new polymer powder from the IAP replaces this process: The powder is added to the liquid sample. The powder’s functionalized surface binds the bacteria efficiently. The pathogens adhere to the 100 to 200 micron powder particles. These can be easily removed along with the microbes in a specially developed system and analysed directly using various microbiological methods. The time-consuming enrichment in a nutrient medium is no longer necessary.

With the new method, food experts can investigate beer and other beverages for infection by pathogens.

“Membrane filtration is not suitable for the quality control of beverages such as fruit juices, milk, cola and red wine. They contain so much solid or suspended matter that the filter clogs quickly,” said Dr. Andreas Holländer, scientist at the IAP.

Breweries have also only been able to examine small sample volumes of up to one liter via membrane filtration. With the polymer powder, tests with 30 liters or more are possible.

“Wherever a small amount of microbes has to be extracted from a large amount of liquid, the new technique can be useful,” Holländer said.

“Through the use of the powder, food safety is increased, since it is more likely to find trace contaminants in large volumes of the beverages,” says Dr. Jutta Schönling, managing director of Gen-IAL.