WHAT IS THE PURPOSE OF THE TEST?
Stress testing is used to assess the growth potential of a selected microorganism (δ) and aims to demonstrate that ready-to-eat foods meet food safety criteria throughout their shelf life. The knowledge gained can be used by the manufacturer:
- in the development of new or revised products,
- in the development of new processes or their modification,
- in the classification of products as ready-to-eat foods in which growth of the test micro-organism may occur or as ready-to-eat foods in which growth of the test micro-organism does not occur during the shelf-life,
- if the initial contamination level of the test micro-organism is known, the growth potential allows the estimation of the final concentration for an identical food, identical strain and the same storage conditions,
- when the growth potential can also be used to calculate the initial concentration in the food that will allow the food to comply with the target limit at the end of its shelf life,
- in the preparation of new packaging.
HOW ARE THE TESTS CONDUCTED?
Our experts collaborate with the technology/quality department to design stress tests for a specific product and microorganism, considering production conditions and manufacturing parameters. Essential to the project is the knowledge of:
- the pH of the product,
- water activity,
- the temperature,
- storage time,
- added preservatives and the presence of starter cultures.
During a site visit, our microbiologist takes intraoperative swabs from which he isolates and phenotypically evaluates strains natural to the production environment. The test product is then contaminated with the strain mixture and incubated at a time and temperature agreed with the customer. The growth potential is calculated from the equation log10 cfu/g T End – log10 cfu/g T0.
WHO ARE THE TESTS FOR?
Load testing is mainly aimed at manufacturers of ready-to-eat foods. If you are a manufacturer and would like to test your products – or learn more about our methods and services, do not hesitate to contact our team today.