Mitigating Microbial Risks Using SurroNov® Surrogate Organisms

Thursday, January 10th, 2019

Foodborne illness outbreaks still cause more than 420,000 deaths per year worldwide (WHO, 2015) with 80 percent of them being related to pathogenic microorganisms like Salmonella, Listeria and E. coli. The mitigation of microbial hazards in food can be achieved in different ways, including the implementation of microbial “kill-steps” like pasteurisation, roasting, drying or extrusion. While traditional control methods based on finished product sampling are widely used, it is important to recognise that they are not sufficient to ensure the safety of processed foods. This is primarily due to the sporadic nature of pathogenic organisms. Indeed, contamination with pathogens usually occurs in a non-homogeneous manner, with such phenomena as “spot” contaminations, where infected food is very hard to identify.

For foods going through a microbial intervention, a key part of the food safety plan is to make sure that the process will repeatedly and consistently be capable to inactivate a sufficient quantity of bacteria—what is more commonly called microbial process validation.

Microbial Process Validation: A Key Tool To Mitigate Microbial Risks

Microbial process validation consists in “obtaining evidence that a control measure or combination of control measures, if properly implemented, is capable of inactivating a target pathogen in a constant and repeatable way” (Codex Alimentarius, 2018). The ability of a process to inactivate a pathogen is usually measured by the log reduction of the pathogen in a target product.

For instance, a 5-log reduction of Salmonella in a spice product, a nut, a flour product, etc. using a thermal process. Process validation is a cornerstone of food safety regulations (U.S. F.D.A. FSMA rules for instance). Process validation generally uses a combination of several methods (Scott, 2005 and Codex, 2008) including the reference to scientific or technical literature, mathematical modeling or realising experimental trials establishing pathogen inactivation. In order to take into account the variability of the processing environment, it is becoming more and more frequent to realise such trials in industrial conditions.

SurroNov® Surrogates: An Easy, Cost-Efficient And Flexible Solution For In-Plant Validation

In-Plant Validation Studies are usually considered a “gold standard” because they provide real-life data on process efficacy. Data generated from in-plant trials provide food processors with the highest level of scientific robustness, as the tests are performed directly on the process to validate, in its real industrial environment. One of the major hurdles for conducting such studies is that it is forbidden to bring pathogenic bacteria in a food environment.

That is why Novolyze has developed SurroNov®, the first range of dried, ready-to-use surrogate bacteria. SurroNov® surrogates are non-pathogenic bacteria that mimic the resistance of foodborne pathogens such as Salmonella, Cronobacter, E. coli, Listeria under different kinds of stress. Due to their safety, they are used directly at the factory (plant, industrial scale) to perform real-life trials and validate the efficacy of a process. SurroNov® surrogates are compatible with a wide range of applications. Due to its capacity to significantly streamline and decrease uncertainty during process validation studies, SurroNov® received several recognitions, including the 2017 Food Safety Innovation Award delivered by the International Association for Food Protection (IAFP) and the 2018 Food Expo Innovation Award delivered by the Institute of Food Technologists (IFT). In addition, the use of surrogate indicators is widely recognised: as a matter of example, Codex Alimentarius 2008 lists the use of surrogates as a method to establish validation of food safety control measures.

During in-plant validation trials, food is inoculated with SurroNov® surrogates at high concentrations and then distributed in the process to validate. Post-processing samples of inoculated food are then collected and enumerated for survivors. Whenever possible, trials are repeated several times (usually up to 3) in order to get significant results. The comparison of SurroNov® surrogates counts before and after treatment allows to confirm a process efficacy. Test results can be documented in a validation report, be included in a company’s food safety documents and be used during customer or regulatory audits.


About Novolyze

Novolyze is a Food Safety company. Our mission is to develop and commercialise innovative technologies to help the food industry manufacture safer food, while ensuring strong compliance with international Food Safety & Quality Standards. Our innovative approach to Food Safety relies on the utilisation of cutting-edge microbiology solutions, combined with the latest developments in digital, IoT and machine learning. Novolyze has offices both in France (Dijon) and the U.S. (Cambridge, MA). Our R&D and production activities are operated from our European headquarter in Dijon, France. Our facilities include BSL-2 Labs, bioproduction units and lab pilot units. Our cross-functional team of validation experts, mainly composed of food microbiologists and process engineers, is able to assist at multiple stages of a validation project.

To learn more about our company & solutions, visit