Colifast Detection Technology

Colifast AS™’ patented technology is comprised of unique media formulations and instrument detection systems, which significantly reduce the time from sampling to result. Traditional microbial testing in the laboratory is time-consuming, whereas Colifast AS™’ rapid and simple test procedures present results within only 2 to 12 hours. No laboratory facilities and minimal skills in microbiology are required to perform the tests from Colifast.


The Colifast technology is based on a chemical reaction between a substrate in the growth medium and enzymes produced by the coliform bacteria. The bacterial enzyme β-D-galactosidase hydrolyses the substrate 4-methylumbelliferyl-β-D-galactoside, which results in the release of the fluorescent product 4-methylumbelliferone (MU).


Monitoring of Water Quality


Human diseases derived from drinking water occur more and more frequently and are a major global health concern. Presence of indicator organisms denotes the potential presence of major pathogens, including viruses and parasites. For monitoring of bacteria in water, Colifast offers tests for E. coli, thermotolerant coliforms, total coliforms, and Pseudomonas aeruginosa. Each of these bacteria has group-specific enzymes that react with complementary substrates in the selective Colifast growth media. Hydrolysation of the fluorogenic substrates results in an increase of fluorescence, which is detected manually or by Colifast instrumentation.

Manual or Fully Automated On-Line Analysis


The Colifast technology combines selective growth media with automated or manual analysers. The change in the intensity of the fluorescence emitted from the media and water sample is a function proportional to the number of target bacteria. The detection of fluorescence with analysers from Colifast enables early warning of bacterial contamination. Analytical results are transmitted instantaneously to the operator in the following formats: MPN, Presence/Absence, and/or CFU/ml. The rapid results give the operator extra time to act and make operational and quality control decisions.

Detection of Spoilage


Spoilage of food caused by micro organisms is a concern worldwide. FAST Fish Test measure the microbial quality of fresh marine fish, and was developed by Colifast and the Norwegian Institute for Fisheries and Aquaculture Research. The test gives a rapid estimation of the content of sulphide producing bacteria (SPB) in fish, which during spoilage give rotten egg- and fishy off-odours. Remaining shelf life of the fish is closely correlated to the bacteria content in the fish. The measurement principle is based upon the formation rate of FeS resulting from the growth of SPB in the liquefied FAST medium. During growth of SPB, ferric iron (Fe3+) is converted to ferrous iron (Fe2+), and inorganic and organic sulphur compounds to sulphide, which precipitates as black FeS . The precipitation, which colours the FAST medium black, is observed visually. The time it takes the bacteria to change the colour from yellow to black is correlated with the number of SPB.