Challenge Testing for C. botulinum Neurotoxin in Food Products

  20/03/2018 09:41:22

Challenge testing for the potential of botulinum toxin formation in chilled and other foods has been a hot topic of conversation for a number of years within the food industry.
 
QIB Extra take the view that challenge testing measuring formation of botulinum neurotoxin is significantly preferable to measuring a demonstrable increase in viable count. As botulinum toxin is the identified hazard, not the presence or quantity of the bacterium per se, it is imperative that botulinum toxin is measured.
 
This is backed up by studies which show C. botulinum toxin formation can occur in the absence of microbial growth, thus the measured absence of growth may give a completely incorrect impression of a safe product. In addition, the direct measurement of C. botulinum in foods is difficult as there is not a culture medium that is selective for C. botulinum, nor is there a medium that provides specific identification of C. botulinum. Simultaneous growth of non-toxigenic Clostridia species with similar morphological characteristics also presents a problem. Thus, challenge testing that relies solely on the detection of an increase in C. botulinum viable count does not follow best practice.
 
At QIB Extra we perform challenge tests that examine the ability of C. botulinum to produce toxin in products over their required shelf-life. Using our state-of-the-art containment facilities, unique collection of C. botulinum strains that are able to grow and produce toxin at chill temperatures and our bespoke in-house ELISA test, we are able to challenge test, and manufacture samples to mimic those produced within a processing environment.
 
To find out more about how QIB Extra can help you with challenge testing and product validation please go to our contact us page.