Challenge Testing

In an ever-changing world where climate change, sustainability and reducing food waste are at the forefront of every business’s priorities, Challenge Testing is a useful tool to help protect your reputation, enhance consumer safety, and get the very best from your product’s shelf life – subsequently helping to reduce food waste and revenue loss.

Challenge Testing: The future of determining shelf-life

Challenge testing is one of several tools used to test what can happen to food during handling and storage, if contaminated with a microorganism. These insightful tests can be carried out using different microorganisms to determine the impact on the shelf life of a food product (including spoilage organisms) and is carried out in order to establish a better understanding of the behaviour of foodborne pathogens such as Listeria monocytogenes.

What happens during Challenge Testing?

The process involves deliberately inoculating a pathogenic bacterium to a food product under controlled conditions, followed by the ongoing testing of the product throughout its shelf life to monitor how the organism behaves. Will it survive? Will it remain below regulatory limits? Or does it exceed limits – deeming it unsafe for consumption? These challenge tests are especially useful in chilled, ready-to-eat foods which naturally have a short shelf life.

Why carry out Challenge Testing?

Under Regulation EC 2073/2005 (on microbiological criteria for foodstuffs), there are specific limits for bacteria which must be complied with throughout a product’s shelf life. In Annex II, regulation goes further and states for Listeria monocytogenes the following: 'when necessary, on the basis of the abovementioned studies, the food business operator shall conduct additional studies, which may include:

Predictive mathematical modelling established for the food in question, using critical growth or survival factors for the microorganisms of concern in the product
Tests to investigate the ability of the appropriately inoculated microorganism of concern to grow or survive in the product under different, reasonably foreseeable storage conditions
Studies to evaluate the growth or survival of the microorganism of concern that may be present in the product during the shelf life under reasonably foreseeable conditions of distribution, storage, and use.
Just because routine testing does not pick up the presence of Listeria does not mean that it is not there, or that it could be there in the future. Predictive modelling based on the product type, pH, Water Activity, and salt levels can only go so far and provide a certain level of assurance that it will not grow or thrive in the food product.'

You need to know, as a food business operator, that your product will still comply with legislation throughout its shelf life, if there is the presence of Listeria.

For more information, please contact ChallengeTesting@Eurofins.co.uk