The identification and differentiation of bacteria date back to the late 1800s. Primary interest often focused on microorganisms impacting animal or human health. Salmonella falls under this umbrella, as it was first identified during a hog cholera study in the 1880s. Early work relied on phenotypic (observable) characteristics due to the limitations of the science at the time, but advancements in science led to the initial development of an antigenic schema for Salmonella. Over the ensuing years, the use of phenotypic and antigenic characteristics helped define the taxonomy of Salmonella (>2600 serovars). These characteristics have also been used for decades in public health investigations involving foodborne illnesses. Linking a Salmonella isolate from an ill human to a Salmonella isolate from a food through serotyping played a critical role in these investigations. Continue Reading

Major developments in the Food Safety Modernization Act (FSMA) have given the FDA new authority under the law. If the FDA decides to conduct a swabathon at your facility, you should expect a minimum of 100 to 300 swabs to be taken and a team of several investigators to conduct the swabathon. Based on the type of swabathon, you may also be required to hold production in your facility. This need is based on several factors, but, in particular, the zones that will be tested.

The FDA’s goal is to find pathogen isolates of Salmonella and or Listeria monocytogenes in and around the processing environment. As an outcome, the FDA will subsequently perform Whole Genome Sequencing (WGS) on these Listeria monocytogenes isolates for their database. The FDA is now swabbing Zone 4 specifically for this purpose, with a WGS analysis of Salmonella expected to follow. The FDA’s zone focus will differ based on the environment and the specific pathogen they are seeking out. For Listeria monocytogenes, you can expect the FDA to begin sampling no sooner than 4 hours into production. Continue Reading

Whether they’re sprinkled on top of a salad, mixed into brownie batter or added as the star ingredient in a granola bar; nuts and seeds tend to find their way into many food products. However, it is vital for food manufacturers to ensure the safety of these items in their products. Tree nuts such as almonds, hazelnuts, pine nuts, pistachios, macadamia nuts, pecans, walnuts and peanuts have been identified as a vehicle for foodborne pathogens, including Enterohemorrhagic E. coli (EHEC), Listeria monocytogenes and Salmonella. Moreover, seeds such as sesame seeds, sunflower seeds and pumpkin seeds have been recently linked to bacterial pathogens. For example, in May 2016, almost 100 products were recalled due to Listeria contamination in sunflower seeds. Salmonella also appears to be of concern in nuts, as it has been associated with many outbreaks and recalls in recent years. Continue Reading

The Food Safety Modernization Act has introduced many new food safety requirements to the food industry. In particular, FSMA places a focus on performing a hazard analysis and using preventive measures in food manufacturing. The requirement to develop and implement supplier preventive controls for raw materials and ingredients to address hazards has renewed interest in methods for sampling and testing raw materials. In order for sampling and testing to be used to address pathogen concerns identified in the hazard analysis of raw materials, a valid sampling plan must be in place. Continue Reading

I once jokingly said during a presentation that there were at least 10 ways to sabotage your food pathogen testing program. While no conscientious food safety leader would set out to negatively impact their own program, the high attention to detail and constant organizational discipline required for an effective testing program leave some room for error. If any small step is not well designed and expertly executed, then your entire program may be worthless – or worse – may cost you millions due to a recall or human illnesses. One factor in particular that manufacturers need to focus their attention on is the reliability of their pathogen sampling and compositing (pooling) strategy, as well as the applicability of their pathogen method. Specifically, what test portion should be taken to ensure accurate results, and what method should be used when testing for the presence of pathogens? Continue Reading