Tracing microbiological contaminants

If you get a problem with an unexpected or unwanted microorganism in your product, what is the best way to go about finding out what it is, where it came from and why it is in your product?

Julie Archer of our Microbiology Department explains how we help clients trace their microbiological contaminants - be they pathogens or spoilage organisms - to help prevent recurrences.

"We have a whole range of standard isolation and enumeration procedures so that we separate the problem organism from the food (and other organisms, if necessary), and in many cases quantify how contaminated a sample is. To identify the organism we take a purified sample and analyse its DNA, which can be compared against a library of microorganisms. The technology is sophisticated enough that identification can be made to strain level.

Test samples

DNA based techniques can be used to identify where a contaminant came from using a specific pattern of fragments (or DNA fingerprint). Ingredients and the processing environment (e.g. machinery, floors and walls, and people) can be 'sampled' to see if organisms with the same fingerprint can be found. This is particularly useful for determining a contaminant source.

We can also assess the growth and survival characteristics of a contaminant organism, which is often of interest to clients.We have found that clients are grateful for help in determining whether the organism will grow or survive in the product under its particular processing and storage conditions."

Contact: Julie Archer
+44(0)1386 842135
julie.archer@campdenbri.co.uk