In recent months food safety has grabbed too many headlines. We’ve seen outbreaks of E. coli from produce, Listeria infections from deli meats, a Salmonella outbreak across 12 states traced to contaminated chicken eggs, and more. In the United States produce alone accounts for 46 percent of pathogen-related illnesses; meat and poultry account for fewer illnesses, but a larger portion of foodborne pathogen related deaths.

Clearly, food chain safety is not at the level that we, as a nation, would like. It’s fair to ask serious questions about the sources of these pathogens. At which processing steps are foodstuffs most vulnerable to contamination? How do we ensure the overall safety of our food before it reaches the table?

At Priorclave, we take pride in supporting new and innovative research for the greater good—and food chain safety is clearly at the foundation of an idea of health and wellness.

Tackling Salmonella at the Source

According to the USDA, Salmonella is the pathogen most associated with food safety incidents, and is a major cause of foodborne illness outbreaks. Many of these Salmonella outbreaks trace back to contaminated animal feed. For example, chickens given Salmonella-tainted feed produce meat and eggs carrying high loads of transmittable, illness-causing pathogens.

Researchers from the United Kingdom and Switzerland took their knowledge of the animal feed production process and pushed it further. Chemical processing to kill pathogens has been largely discontinued, as it results in unsafe working conditions. Fortunately, in most mills the process of forming mash into feed pellets includes a conditioning and retentioning process that is generally done at heats high enough to reduce microbial loads. It’s often assumed that this is basically equivalent to a true “kill-step” in the feed production process.

But how effective is that step at killing dangerous pathogens? The researchers wanted to learn how the interaction of moisture content and heat processing affect the efficacy of the kill-step. Specifically, they investigated processing time and moisture control to discover the best way to treat common heat-resistant Salmonella strains in low-moisture feed. Dry processing conditions typically require significantly higher heat and longer processing times to act as an effective kill-step. Besides being inefficient in terms of both time and resources, these conditions are much more likely to also destroy nutrients in the feed.

Using Priorclave Technology to Explore Strategies for Reducing Salmonella Contamination in Animal Feed

In a study titled, Microbiological Assessment of Heat Treatment of Broiler Mash at Laboratory Scale to Evaluate Salmonella Reduction during Feed Conditioning, the UK and Swiss research team used a custom, compact Priorclave 40L Benchtop steam autoclave for process testing, with the goal of designing a validated kill-step that could fit into the existing production process. Their Priorclave was custom-built to run from saturated steam, with an enlarged vent pipe to allow rapid steam evacuation and a door interlock system set to allow sample access within seconds after the heat cycle. These customizations allowed the investigators to more closely replicate real-world processing conditions. This, in turn, increased the likelihood of validating a process that could be scaled up from the lab to industrial manufacturing. Since every Priorclave is individually assembled in their own U.K. facility, collaborative customization like this is much more feasible.

Using their customized Priorclave, the research team processed 5 g samples of inoculated feed at rapid heat (reaching 185℉  in about 20 seconds) and cooling to access samples within about 3 seconds of terminating the process. The investigators concluded that targeted processing with recontamination prevention can reduce risk of Salmonella microbes in animal feed. By controlling the moisture content, they were able to determine basic methodology for validation studies, which could then be scaled up for industrial application.

The Right Autoclave for Every Lab

While having a customized Priorclave certainly helped fine-tune the process necessary for this investigation, even a standard Priorclave offers researchers a great deal of flexibility. These highly programmable units are designed and built for research> They allow for easy access to the most useful features (like one-button start and media cycles with delayed start and post-cycle media warming) while still giving you full access to custom cycle times, temperature and pressure ramps and set points, and so on. Priorclave autoclaves are designed to maximize internal volume while minimizing water and energy use, meeting or exceeding labs’ efficiency standards.

Looking for an autoclave that will get more done with less hassle? Reach out to Priorclave today, and let our autoclave experts help you find the solution you need.