Tag Archives: pathogen detection

3M Molecular Detection Assay 2

3M Receives Edison Award in Diagnostics

3M Molecular Detection Assay 2

3M has announced that its Molecular Detection Assay 2 has won the Gold Edison Award in the diagnostic tools category. The 2017 Edison Awards recognize innovators that have had a positive impact globally. The assay platform is a next-generation of tests, which also previously won an Edison award.

The technology is powered by isothermal DNA amplification and bioluminescience detection to provide a faster molecular detection of pathogens. Its single assay protocol enables batch processing of up to 96 different samples simultaneously and can provide same-day results.

The platform can be used to identify Salmonella, Listeria, Listeria monocytogenes, and E.coli O157 in food or environmental samples, and Cronobacter in powdered infant formula.

BAX-System_X5_Hero

Hygiena to Acquire DuPont’s Food Safety Diagnostics Business

By Food Safety Tech Staff
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BAX-System_X5_Hero

In an agreement expected to close in Q1 2017, Hygiena, a provider of rapid food safety and environmental sanitation testing, is acquiring Dupont’s global food safety diagnostics business. Financial terms of the deal were not disclosed.

The acquisition includes DuPont Diagnostics’ BAX system for pathogen detection (used globally by food manufacturers, quality labs and governments worldwide) and RiboPrinter Systems, the company’s globally and technically trained sales, R&D and manufacturing, and its in-house production capacity.

“The combination of DuPont Diagnostics and Hygiena will create a broad food safety diagnostics company that can better serve our customers, said Steve Nason, CEO of Hygiena in a press release. “The combined company’s microbiology products will cover the full manufacturing process, from in-process environmental tests to finished products tests.”

Hygiena is a portfolio company of private equity firm Warburg Pincus. Its products are distributed in 80 countries and include rapid hygiene monitoring systems, environmental collections systems, and its ATP testing system.

New Dipstick for Rapid Detection of Salmonella on the Farm

By Food Safety Tech Staff
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A new rapid assay may help growers make faster and more informed decisions right on the farm. Researchers from the University of Massachusetts and Cornell University are developing a test that addresses the challenge of sampling produce and assessing risk in a timely manner. The dipstick would enable rapid detection of Salmonella in agricultural samples in about three hours.

How It Works

“Users simply place a leaf sample in a small plastic bag that contains enzymes and incubate it for about 1.5 hours. Users would then squeeze a small liquid sample through a filter and place it in a tube with bacteriophages—viruses that are harmless to humans but infect specific bacterium, such as Salmonella or E. coli. Some phages are so specific they will only infect one bacterium serotype while others will infect a broader range of serotypes within an individual species. Phages also will only infect and replicate in viable bacteria, ensuring that non-viable organisms are not detected. This distinction is useful if prior mitigation steps, such as chlorination, have already been used. The phages used in the test were engineered to insert a particular gene into the bacteria.” – Center for Produce Safety

“We have been developing dipstick assays for ultra-low detection limits,” the technical abstract, Rapid bacterial testing for on-farm sampling, states. “Our preliminary data suggests that our fluorescent dipstick will have a detection limit of Salmonella spp. cells which makes the test ideal for on-farm use and appropriate federal requirements.”

Role Play: Be FDA for a Day

By Food Safety Tech Staff
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Mary Duseau, chief commercial officer at Roka, will review a self-auditing program that companies can use to essentially play FDA for a day—using technology that identifies hidden risks in a food processing facility.
During the webinar, Mary Duseau, chief commercial officer at Roka, will review a self-auditing program that companies can use to essentially play FDA for a day—using technology that identifies hidden risks in a food processing facility. REGISTER HERE

Food company executives are in a new world of criminal liability as they navigate a different regulatory environment. During a free webinar next month, attendees can learn how to Play FDA for a Day. Roka Bioscience, along with food safety attorney Shawn Stevens, will discuss:

  • How to navigate the regulatory environment
  • Impact of Whole Genome Sequencing
  • Using accurate pathogen detection technology
  • Self-auditing of food facilities to avoid regulatory or criminal exposure

“Ensuring your CEO stays out of prison is a great ROI. Food company executives and managers need to perform additional testing to see what FDA will find, and then correct it, before FDA arrives in their facility.” – Shawn K. Stevens

Shawn K. Stevens, Food Industry Counsel Check out the latest insights from Shawn K. Stevens in his column, Food Safety Attorney

During the 2016 Food Safety Consortium, Shawn Stevens will lead the following panel:

Thursday, 12/8

10:30–11:15 AM

Ask the Experts: Strategies to avoid FDA criminal liability
Round table discussion group lead by Shawn K. Stevens, Global Food Safety Attorney, Food Industry Counsel LLC

LEARN MORE

John Besser, Listeria conference

Deadly Outbreaks and the Role of Metagenomics

By Maria Fontanazza
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John Besser, Listeria conference

Americans consume 350 billion pounds of food each year, with one out of six people falling victim to foodborne illness, and 3000 dying. The significant amount of Listeria outbreaks hitting the industry (most recently, the staggering number occurring in produce) has left many food safety and quality assurance professionals searching for better methods of prevention and detection. Using big data, specifically metagenomics, to improve food safety and detect potentially deadly outbreaks is indeed where the future is headed.

DID YOU KNOW? The estimated U.S. cost of one case of Listeriosis is $1.4 million. Listeria is a prime concern due to the high percentage of fatalities that occur as a result of contracting Listeriosis. And what’s worse is the fact that many of the cases are preventable.

During Food Safety Tech’s Listeria Detection & Control Workshop this week, John Besser, Ph.D., deputy chief of CDC’s Enteric Diseases Laboratory Branch, outlined how the agency is leveraging metagenomics to find unrecognized problems in the food supply. Perhaps the most important element of disease surveillance is that it enables the detection of new issues, especially those whose presence was previously unknown.

John Besser, Listeria conference
CDC’s John Besser, Ph.D. discusses genome-based outbreak detection work at the agency. (Click to enlarge)

Pathogen-specific surveillance allows the detection of more outbreaks, which will in turn make the food supply safer, because it will enable industry to understand the root causes of outbreaks and help them address problems much sooner. The CDC is focused on genome-based outbreak detection because of its ability to achieve faster detection—and with greater precision in identifying the source. The method has also helped the agency solve outbreaks with fewer cases occurring, and it concurrently helps rule out sources.

PulseNet, a nationwide database (comprised of 87 labs in the United States) that links cases most likely to share a cause for illness, has prompted food safety improvements across a variety of products, including sprouts, peanut products, leafy greens, flour, melons, eggs and poultry. Combine this capability with the Listeria initiative, which was launched in the mid-2000s, and the CDC has been able to find more (and smaller) outbreaks than ever before. In fact, there’s been a dramatic increase in the number of outbreak cases that have been solved (with the food source being identified). During the pre-whole genome sequencing (WGS) stage (September 2012­–August 2013), only one outbreak was solved; in year one of the WGS project (September 2013–August 2014), four cases were solved; in year 2 of the WGS project (September 2014–August 2015), nine outbreaks were solved. In these respective time periods, the median number of cases per cluster dropped from six to four to three. In addition, the number of cases linked to a food source jumped from 6 to 16 to 93 during this respective time period.

Besser also discussed the role of metagenomics, or the study of total genetic material recovered directly from environmental samples. A couple of years ago, this was science fiction and wasn’t possible, he said. But as we look to the future, metagenomics will become a lot cheaper as computers become more powerful—and at break-neck speed. He referenced IBM Research, who earlier this year announced a project being conducted in conjunction with Mars, Inc. and Biorad for sequencing the food supply chain (calling it the “largest-ever metagenomics study”).

Read Food Safety Tech’s interview with IBM Research about the next-generation sequencing project, “Preventing Outbreaks a Matter of How, Not When”

Metagenomics enables the profiling of communities of microbiomes anywhere in the food supply chain. And the method is fast—it can potentially shave weeks off the process of identifying clusters of interest. In addition, it can increase the value of interviews conducted with patients who have fallen ill (Think about it: Do you remember what you ate two weeks ago? What about a month ago?).

Currently there are several limiting factors surrounding metagenomics: Cost; sequencing read length and error rate; specific software (and pipelines); computing processing power and bandwidth; and the signal-to-noise factor. However, with the rapid rate in which technology has been improving in this space, the high likelihood of these issues being addressed and resolved in the not-so-distant future will present exciting opportunities in outbreak prevention and detection.

Clear Labs, The Hamburger Report

Next-Gen Genomic Sequencing Exposes Problems with Burgers

By Maria Fontanazza
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Clear Labs, The Hamburger Report

Burgers are the quintessential American food. But as prices continue to rise in the beef industry and U.S. consumers seek more health-conscious alternatives such as veggie and salmon burgers, some food companies may be cutting corners. Clear Labs used next-generation genomic sequencing (NGS) to conduct molecular analysis of 258 burger products (ground meat, frozen patties, fast food burgers and veggie burger products from 79 brands and 22 retailers) and found significant issues—instances of substitution, missing ingredients, pathogens or hygienic problems—in about 14% of samples. This is a red flag for industry, indicating a need to remain vigilant about vulnerabilities in the supply chain and the way in which products are tested.

Ironically, perhaps the biggest problems that The Hamburger Report revealed surrounded meat-alternative products. Out of 89 vegetarian samples, 23.6% were found to have issues, from ingredient substitutions to rat DNA to pathogens (see Figure 1). “We were surprised by the higher rate of problems in veggie burgers,” says Mahni Ghorashi, co-founder of Clear Labs. “There were nearly twice as many problems in those samples as their meat counterparts, which is surprising, because you normally think of a veggie product as perhaps a safer bet, but we actually found more cases of pathogen strains. And we found things like beef in veggie products, which isn’t acceptable. That was somewhat troubling.” Ghorashi suggests that manufacturers should be doing more to ensure consistency and adequate labeling of best-handling practices for consumers. “The message is that we need more awareness about the unknown risks and the potential need for more stringent safety measures,” he says. “We follow a great deal of these practices when it comes to meat-based products. Perhaps we’re not as sensitive toward veggie-based products.”

The Hamburger Report, Clear Labs
Figure 1. The Hamburger Report found a higher rate of issues with meat-alternative burger products. (Figure courtesy of Clear Labs)

The report also uncovered several high-risk pathogens in samples, but not the typical ones (i.e., Listeria, Salmonella, E. coli) that make news headlines. Out of the 258 samples, 4.3% contained pathogenic DNA, with vegetable products accounting for four of those instances. Pathogens found included Yersinia pseudotuberculosis, Yersinia enterocolitica, clostridium perfringens, and klebsiella pneumonia. Although these strains are often rare, they still have health implications and can cause tuberculosis-like symptoms, digestive issues and gastroenteritis. Typical methods such as polymerase chain reaction (PCR) are used to detect pathogenic strains such as Listeria, Salmonella and E. coli, but can potentially miss other strains. “The industry should take off their pathogen blinders and start to test for lesser known and potentially dangerous pathogens using these types of blind-testing techniques,” says Ghorashi. “It’s worth casting a wider net and filter in order to catch these [pathogens].”

Although the screening method that Clear Labs used is currently unable to determine whether a pathogen is dead or alive, nor the count, there are other benefits to using next-generation DNA sequencing, says Ghorashi, who thinks the method has the potential to become the technology of choice in the food industry. “The strength of this platform as it differentiates itself from existing solutions is its ability to look unbiasedly and universally into food samples and tell you everything that’s there,” he says. “It’s able to detect any type of DNA-based species within a sample as opposed to specific queries that you might be looking for. This technology can detect everything that’s there, so it often catches things that one might miss. Existing solutions look very focused on one particular item.”

What are the implications of The Hamburger Report in the context of FSMA?

Ghorashi: It’s very much in line with what FDA is rolling out with FSMA. This speaks back to where industry is headed in terms of rolling out more preventive measures versus responsive measures. It plays into economic adulteration and fraud. It also plays into the concept of proactive testing and measures, a better sense of the overall landscape of the supply chain and where the weaknesses are. These are all the areas that software-driven and data-driven platforms can help emphasize. We look at FDA as a forwarding-thinking organization and an ally in this initiative. Hopefully emerging companies, including ourselves, that have new disruptive technologies can help assist the food industry, whether producers, manufacturers, retailers or distributors, in building more air-tight safety programs and complying more closely with FSMA regulations.

Clear Labs is working towards building out its first product, Clear View. The software data analytics platform integrates NGS technology and is designed to aggregate test data in the cloud to provide food manufacturers, suppliers and retailers with insights about their supply chains. The company is also continually growing its internal database, which, according to Ghorashi, is currently the largest molecular food database in the world.

Gina Kramer
Food Safety Think Tank

Rapid, On-site Pathogen Testing a Game Changer

By Gina R. Nicholson-Kramer
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Gina Kramer

Learn innovative ways to mitigate the threat of Listeria at the Listeria Detection & Control Workshop | May 31–June 1, 2016 | St. Paul, MN | LEARN MOREWaiting days for test sample results can be the difference between keeping consumers safe and allowing contaminated food to enter the supply chain. I recently spoke with Mark Byrne, president and CEO of start-up ProteoSense, about his company’s portable pathogen detection system, which can find foodborne pathogens in food and environmental samples in 15 minutes or less, with no incubation required. Licensed from Ohio State University, the technology, called RapidScan, has unique sensor technology that provides a sensitive and specific assay with very low noise to enable a direct measurement of the presence of a pathogen.

When I asked Mark what effect he thought this technology would have on the food industry, he said: “I think the effect is going to be very profound. First of all, anytime you can give management information quickly, it changes their ability to respond, to take action.”

The technology has the potential to help companies deliver food to consumers safer and faster, and with less waste. Samples can be tested at various parts of the food supply chain, from in the field to final packaging.

RapidScan has been demonstrated for Salmonella, and ProteoSense is working on a Listeria assay. If all goes as planned, we can expect to see the product on the market in 2017. Watch my discussion with Mark to learn more about this innovative technology and how it could help you mitigate risks in your supply chain.

 

Listeria

Listeria Workshop to Tackle Prevention, Detection and Mitigation

By Food Safety Tech Staff
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Listeria

More effective environmental monitoring and improved sanitation practices, along with databases such as PulseNet, are helping the industry find Listeria contamination. However, once detected, many processing facilities have difficulty removing the bacteria.

Next month Food Safety Tech is holding a Listeria Detection & Control Workshop to educate food industry professionals about how to integrate prevention and mitigation procedures into existing sanitation, operation and testing programs. The two-day workshop, which takes place May 31 – June 1 in St. Paul, MN, will cover the basics of controlling Listeria, along with the following topics:

  • Detecting and penetrating biofilm
  • How to build an effective environmental testing program
  • Producing reliable testing to detect and control Listeria
  • Sanitation departmental role in prevention, control and mitigation
  • Building a master sanitation schedule
  • Innovative Listeria mitigation programs
  • Gaps in proactive food safety programs
  • Hygienic equipment design

Industry speakers include:

  • John Besser, Ph.D., deputy chief, enteric disease laboratory branch, CDC
  • Gina (Nicholson) Kramer, Savour Food Safety International
  • Dominique Blackman, Realzyme
  • Janet Buffer, The Kroger Company
  • Ken Davenport, Ph.D., 3M Food Safety
  • Bert de Vegt, Micreos Food Safety
  • Joellen Feirtag, Ph.D., University of Minnesota
  • Melinda Hayman, Ph.D., GMA
  • Sanja Illic, Ph.D., Ohio State University
  • Paul Lorcheim, ClorDiSys Solutions
  • Douglas Marshal, Ph.D., Eurofins Scientific
  • Jeff Mitchell, Chemstar
  • Megan Murn, Microbiologics
  • Robin Peterson, Micreos
  • Errol Raghubeer, Ph.D., Avure Technologies

The event takes place at the 3M Innovation Center in St. Paul, Minnesota. Workshop hours are Tuesday, May 31 from 11:00 am–6:00 pm and Wednesday, June 1 from 8:30 am–5:00 pm. For more information, visit the Listeria Detection & Control Workshop event website.

In the Food Lab

New Dynamics in Environmental Testing

By Erin Dreyling, Ph.D
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Recent recalls and outbreaks associated with Listeria coupled with FDA’s finalization of the FSMA preventive controls rule have heightened the industry’s need to focus on environmental testing programs. The need for a preventive control program with higher resolution is especially highlighted by the government’s increasing use of whole genome sequencing data to more rapidly link human illness to food processing establishments. I work with many customers who simply do not recognize all of the factors that influence their ability to detect Listeria in environmental samples. For many, an environmental sample is collected, shipped to a third-party lab, results are received within two to four days, and few questions asked. Most companies have not invested the time and resources needed to truly understand how each component of an environmental sample impacts their ability to detect Listeria. So what factors should be considered to maximize Listeria detection in the plant environment?

Learn innovative ways to mitigate the threat of Listeria at the Listeria Detection & Control Workshop | May 31–June 1, 2016 | St. Paul, MN | LEARN MOREListeria is a True Survivor

Listeria is inherently a hearty organism that can withstand highly adverse conditions in the plant environment. It is able to survive and grow across a wide range of temperatures, including refrigeration, and it is more tolerant to heat than Salmonella and E. coli. Additionally, the organism survives across a wide pH range, including extended periods in highly acidic conditions, and can survive food processing and preservation with up to 25.5% salt. These traits may result in highly injured Listeria being collected in environmental samples, and requires optimization of the sample collection and analysis process in order for detection and culture confirmation to occur.

Sanitation Programs May Not Destroy Listeria

Sanitation practices are intended to destroy Listeria in the plant environment, but not all sanitizers will be 100% effective. In some cases, sanitizers may not fully kill Listeria, leaving highly injured Listeria that may require an extended lag phase in order for growth and detection during testing. Sub-lethally injured Listeria remains a food safety concern, as the bacteria maintain the ability to recover and flourish in a nutritive environment. Additionally, Listeria readily forms biofilms in the plant environment, which many traditional sanitizers do not effectively remove. Biofilms in the plant environment may maintain low levels of Listeria that may be challenging to detect without the use of a sensitive detection method.

Sample Collection: Choose the Right Tool for the Job

The neutralizing and nutritive capacity of the collection media used with the collection device can have a significant impact on the ability to resuscitate, detect and culture stressed Listeria. When selecting a collection media, it is important to ensure that the media will effectively neutralize the sanitizers used in the plant environment. For instance, peroxyacetic acid and quaterinary ammonia-based sanitizers will not be neutralized well by commonly used collection media such as Neutralizing Buffer or Letheen Broth. Neutralization of the sanitizer in environmental samples is important in order for resuscitation and growth of any Listeria present within the sample. Additionally, use of a collection media that contains nutrients to begin the resuscitation process for Listeria immediately upon collection is also important for detection and culture confirmation of Listeria in samples. Collection media such as Neutralizing Buffer contains monopatassium phosphate, sodium thiosulfate, and aryl sulfonate complex intended only to neutralize sanitizers. Conversely, D/E Broth and HiCap Broth have components to nourish Listeria and facilitate resuscitation in addition to neutralizing sanitizers.

Enrichment Media Determines Recovery & Growth

Enrichment media plays a major role in the speed of recovery and growth of Listeria in environmental samples. Medias that facilitate faster recovery of injured Listeria allow for shortened lag phases facilitating more rapid growth. Enrichment media that facilitate faster recovery and growth allow Listeria to reach the limit of detection for screening tools more quickly. When paired with a highly sensitive method, enrichment media, which foster greater Listeria growth and recovery, can allow for significant reductions in time to results for screening methods. Additionally, faster recovery and growth of Listeria due to enrichment media can increase the likelihood of culturally confirming Listeria found at low levels pre-enrichment.

Not All Detection Methods are the Same

The ability of a detection method to find Listeria in an environmental sample is impacted by two factors: 1) method sensitivity and 2) method robustness in the presence of sanitizers. The more sensitive a rapid test method, the greater the chance of finding low levels of Listeria in an environmental sample. Low levels of Listeria in environmental samples are likely due to the injured state of Listeria in the plant environment post sanitization. Immuno-based rapid methods have a sensitivity of 105–106, DNA-based methods have a sensitivity of 104–105 and RNA based methods have a sensitivity of 102–103. Using an RNA-based method offers 1 to 2 logs greater sensitivity and greatly increases the chance of finding low-level Listeria.1 This can be particularly true when sampling conditions such as collection media or enrichment media are less than optimal for the neutralization of sanitizers and growth and recovery of Listeria.

Another important factor that influences a test method’s ability to detect Listeria in an environmental sample is the method’s ability to amplify and detect the organism in the presence of sanitizers. Most molecular-based methods do not include a sample clean up step resulting in sanitizer being present during the amplification step. For some methods, sanitizers may inhibit amplification, resulting in indeterminate or false negative results.

Confirmation Requires Optimization of the Sampling Process

The ability to culturally confirm a Listeria sample that screens positive is influenced by the entire environmental sampling process. In order to culture confirm samples with highly injured, low-level Listeria, it is necessary to optimize the sample collection media, enrichment media, and confirmation process to provide the greatest likelihood of culture recovery. If Listeria is not adequately resuscitated and able to achieve sufficient growth, the level of Listeria present in the sample post-enrichment may be below the limit of detection for culture. The likelihood of culture confirmation can be increased by incorporating steps such as a secondary enrichment or concentration via IMS capture. Culture confirmation for samples that screen positive on a rapid method can be especially challenging if a highly sensitive test method is used for screening that may detect Listeria at lower levels than culture. Thus, optimizing the environmental sample program is especially important if confirmation of screening results for highly sensitive methods is desired.

Method Sensitivity and Increased Positivity

Employing a highly sensitive screening tool for environmental samples provides a better lens to view risk within the food safety processing environment. Many companies fear that a more sensitive method will result in significant increases in positivity and cost for increased sanitation. In working with customers who have moved from immune-based methods to a highly sensitivity molecular method, I’ve observed an initial increase in positivity followed by a leveling off of low-level positivity after enhanced interventions are taken in the plant. Companies that proactively seek out and destroy Listeria in their plants are then able to maintain low level rates of positivity with routine cleaning measures, while also maintaining the confidence that they are using the best tool available for Listeria monitoring.

Understand Your Risk & Establish a Culture of Food Safety

It is important for food safety professionals to fully consider the hidden risks that may exist in their plant environment due to the environmental sample process masking the true presence of Listeria. Each component of the environmental monitoring process, sanitizer, collection media, enrichment media, detection method and culture process plays an important role in a company’s ability to be able to detect and culture confirm Listeria in the plant environment. Optimizing each step within the environmental sample process allows a company to be proactive instead of reactive. This approach creates a company culture of food safety that can seek out, detect and destroy Listeria in the plant environment, can significantly mitigate risk. The good news is that by incorporating the right food safety culture and making data-driven choices, today’s manufacturer can achieve both short-term dividends of risk reduction as well as a long-term elevation of control of its process.

Reference

  1. Culture Shift: The New Dynamics of Listeria Environmental Control and Testing. Roka Bioscience, Webinar.

Safe Food: A Product of a Clean Environment

By Gina R. Nicholson-Kramer
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Most recently we have seen an increase in foodborne illness outbreaks from Listeria to Salmonella to Norovirus to E.coli, many of which are a result of post-lethal contamination of processed foods. This is often a direct result of a gap in the sanitation programs that were in place at the processing facilities. Every facility should conduct a sanitation gap analysis on an annual basis. In order to receive unbiased feedback, this activity is best performed by a third party that is not a chemical provider.

Join Gina Kramer at the Listeria Detection & Control Workshop, May 31–June 1 in St. Paul, MN | LEARN MOREDeveloping and implementing a sound environmental hygiene program at a food processing facility is essential to its success in producing safe food for consumer consumption. There are fundamental basics of sanitation that every plant must follow in developing a strong program. The fundamental basics include: Developing sanitation standard operating procedures (SSOPs) for; Floors and drains, walls, ceilings, equipment and utensils, and employees. SSOPs must also contain perimeter control, foot traffic control into food preparation areas, zoning, and environmental sampling procedures.

Jeff Mitchell, Gina Kramer, Listeria
VIDEO: Jeff Mitchell and Gina Kramer discuss the increase in Listeria recalls. | WATCH NOW

When developing SSOPs, using the proper risk reduction formula will lead to sanitation success. To determine the best risk reduction formula, I sought the advice of sanitation expert, Jeff Mitchell, vice president of food safety at Chemstar. Before working for Chemstar, Mitchell was the Command Food Safety Officer for the United States Department of Defense (DOD). Serving more than 20 years for the DOD has given him the opportunity to visit thousands of processing facilities all over the world, seeing the best and the worst, and assisting in finding the root cause of contamination issues and negative environmental sampling results. In this article, I share Mitchell’s risk reduction formula for sanitation success and how to use the formula to build a solid and successful sanitation program.

Foundational Science

“An understanding of the difference between transient and persistent (or resident) pathogens is a key part in the foundational science of sanitation solutions,” explained Mitchell as we discussed the details of the risk reduction formula. Transient pathogens are those that are introduced to the processing facility from the external environment. Entrance occurs from deliveries on transportation vehicles and pallets, food, and non-food products and its packaging, employees and visitors, pests and rodents, along with leaks in the roof or improper cleaning of drains, which are known reservoirs.

Kramer_FoundationalScience“Persistent pathogens are those pathogens that establish residency within the processing facility. Most bacteria will aggregate within a biofilm, allowing them to live in communities. A biofilm is a survival mode for the bacteria; it protects it from sanitizer penetration. The biofilm layers actually masks it from sampling detection. You could swab a surface or an area and not get a positive pathogen test result, because the biofilm is masking it,” Mitchell stated. He continued to explain that most contamination risks are likely from established populations. Four things need to exist for resident populations to form: Pathogen introduction, water, trace organics and niche area for attachment and growth. Food processing facilities should be most concerned about these populations, as they’re being traced to many recent outbreaks and recalls.

In his experience, Mitchell shared that sanitation efforts should focus on areas within the processing facility where moisture and nutrients are collected; both are needed for biofilm formation. Disruption of these niche areas containing biofilm can result in direct (food contact) and indirect (non-food contact) contamination if the biofilm is not completely penetrated or removed. This can occur through active and passive dispersal of pathogens. Active dispersal refers to mechanisms that are initiated by the bacteria themselves where they naturally eject from the biofilm and land on other surfaces. Passive dispersal refers to biofilm cell detachment that is mediated by external forces that shear the biofilm, causing it to move and further spread. This can be caused through fluid shear, abrasion and/or vibration due to power washing, equipment vibration, or deep cleaning/scrubbing that does not penetrate and remove all the aggregate layers of biofilm. In other words, the biofilm and pathogens are just smeared around the facility like cleaning a mirror with a greasy wiping cloth.

Chemistry and Application

Kramer_CleaningMatrixThe cleaning matrix must be considered to properly remove soils that house both transient and persistent pathogens. This is done by combining proper cleaning and sanitizing agent concentration (PPM), adequate exposure time, proper temperature and mechanical action (agitation) or good old elbow grease. If there is a decrease in one area of the matrix, then an increase in the other areas needs to be made as an accommodation to the cleaning process. My years working in industry have taught me that the most expensive quadrant of the cleaning matrix is agitation, because it requires manual labor. Reduction of labor is one of the first ways companies build in efficiencies to increase profit margins. That means a solution must be built that focuses on temperature, concentration and proper contact time to produce the sanitation results necessary to prevent persistent pathogens from establishing residency within processing facilities.

Temperature should be regulated by the type of soils that need to be removed. High fat soils need a higher temperature of about 140⁰ F. However, when removing high protein soils, the temperature needs to be reduced so that the protein is not baked onto the surface. Baked proteins that are not removed become nutrients for bacteria to aggregate and reside. High temperature is does not work in every food processing plant, Jeff explained.

Proper balance of detergent and sanitizer is necessary to remove and destroy both transient and persistent pathogens. The detergent needs to be the right formulation and contact time to break down soils and biofilms with application of the right concentration and contact time of sanitizer to kill the exposed pathogens. Without the right balance in place it can create the perfect storm for spread and contamination within the processing facility.

Validation

Do your homework. Research is the most valuable tool when validating the effectiveness of a cleaning process. Private research is good but not the only form of validation on which to base a business decision. I have found that peer reviewed published research is best to use in validating all quadrants of the cleaning matrix. Academic research based on sound science that has practical application results is worth the investment to make sound business decisions.

Many products have been developed to penetrate and destroy the biofilm layers that bacteria aggregate. Again, do your homework. Choose a product that also provides a pathogen kill once the biofilm has been penetrated. I cannot stress enough to make sure that the SSOPs follow the manufacturer’s validated processes and the sanitation team follows the SSOPs’ directions.

Solution

Applying the desired solution requires dividing the processing facility into zones to designate specific sanitation requirements. This will assist in the development of specific SSOPs that apply the right solution in the right zone throughout the site.

Kramer_ZoneMitchell also gave great advice about cleaning tools and cleaning chemical basics. He explained that a facility should color code the cleaning tools according to zone and only use them in the designated zone area. This prevents cross contamination from occurring, because cleaning tools can be vehicles of contamination transfer. Utilize foam detergents and foam sanitizers as they are more forgiving and increase contact time, and sanitation crew can see where they have applied the chemicals. Use the Ross-Miles foam test for stability: Foam should last more than three minutes before breaking and turning into a liquid solution that runs down the drain, costing a site money and opening up the potential for introducing pathogens into production rooms.

Mitchell advised the development of sanitation procedures that focus on daily thorough cleaning of everything from the knees down in Zones 1-3. “You want to knock everything down and keep it down. The objective is to keep bacterial creep from occurring,” he said. “Creep is where bacteria are moved by processes like water spray, splash and aerosolization, causing the bacteria to move from one area (it usually develops on the floor) to then move up walls and the legs of equipment, etc.— eventually causing contamination of food during food production and packaging.” Obviously, all food contact surfaces in Zone 1 need to have specialized SSOPs according to the equipment, food processing shifts per day, and type of foods that are being processed.

Mitchell stressed that perimeter and foot traffic control entry programs should incorporate a good foam sanitizer that stands up to the Ross-Miles test with optimal duration of five minutes. The distribution of the foam should cover a large enough area that the employees’ foot path and equipment must travel through the foam to achieve contact to control transient pathogen entrance into Zones 1–3. Concentration levels of these areas should be at least double what the food contact area strength is for effectiveness of log kill needed for control.

Environmental monitoring procedures should follow the zoning process set up for sanitation. “Swabbing for Adenosine Triphosphate (ATP) and/or Aerobic plate count (APC) are tools that can be used to help identify biofilm locations. One thing to note is that the bacteria located under the biofilm are in a modified dormant state requiring less energy and making less ATP available for detection.  With that said, ATP and APC swabbing are still both viable tools to use in sanitation verification,” said Mitchell. If you only test for general risk pathogens in your facility you may receive false negatives due to biofilm masking the pathogen from showing up as a positive in environmental testing. Utilizing both general pathogen, ATP and APC in concert, is the best combination in a facility’s environmental monitoring program. The goal is to seek and find then destroy and verify.

I recently discovered a great biofilm visual detection test from Realzyme that is wonderful to use to verify whether the sanitation system in place is working. It can also differentiate between protein build-up and biofilm formation. In my professional opinion, this visual detection test is essential to incorporate in a robust environmental testing system.

Safe Food: The End Product

Our responsibility as food safety/quality professionals is to provide the safest, most delicious food for our customers to enjoy. To ensure safe food in our end product, we need to develop a robust sanitation and environmental testing program that follows the risk reduction formula (Foundational Science + Chemistry & Application + Validation = Solution) and conduct an annual sanitation gap analysis by a third-party expert for continuous improvements.

Apply these steps to protect your food, protect your brand and protect your customers so that they Savor Safe Food in every bite!