NBB®-B-Am Broth

Detection of biofilm indicator microorganisms

Biofilms are accumulations of various microorganisms which can develop into complex colonies over time. Starting out with ubiquitous bacteria, such as acetic acid bacteria and mucous-forming microorganisms which commonly form on substrate residue in inaccessible sections on the filling line, a biofilm gradually establishes the ideal conditions for beer and beverage-spoiling microorganisms; even for strictly anaerobic bacteria such as Pectinatus and Megasphaera. If the biofilm breaks apart, the bacteria are spread throughout the environment by aerosols which may lead to the contamination of individual bottles. This is called scatter contamination or secondary contamination.

The ready-to-use NBB®-B-Am Broth allows weak points in your production and filling to be monitored continuously through the detection of indicator bacteria for biofilms using smear samples. Sampling with sterile swabs is performed at defined critical points 1-2 times a week. The samples are then incubated in NBB®-B-Am Broth and analysed for indicators such as acetic acid bacteria or mucous-forming microorganisms, etc. A positive test result is indicated when the colour changes from red to yellow. The number of positive results is then documented as a percentage.

The biological condition of a non-sterile production facility is regarded as non-critical if the number of positive results remain below the safety limit of 20% - 30%. Percentages above the limit values, or increasing numbers of positive results over a period of several weeks indicate the development of persistent biofilms. The production line must be thoroughly cleaned and disinfected to return to the non-critical range and prevent any risk of secondary contamination.