Tag Archives: Listeria

Alert

Is Your Condensation Under Control?

By Food Safety Tech Staff
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Alert

“Drop the Mop! Take a Clean New Look at Condensation Control in Food Processing Facilities” is available on-demand Little beads of water on overhead surfaces can cause big problems. Remember the Listeria contamination that affected Blue Bell Creameries? FDA investigators spotted condensation dripping right into food and food contact surfaces. In a response to an FDA Form 483, Blue Bell wrote “As part of our internal review, we are extensively reconfiguring lines and equipment to eliminate the potential for condensation forming on pipes above processing equipment”.

Condensation can form on overhead surfaces during sanitation processes, which poses potentially serious issues. During an upcoming webinar, “Drop the Mop! Take a Clean New Look at Condensation Control in Food Processing Facilities”, experts from the University of Nebraska, Maple Leaf Foods, General Mills, Smithfield Foods, and 3M Corporate Research Materials Laboratory will discuss tips on how to manage condensation, along with the challenges associated with condensation.

Sprouts

FDA’s Draft Guidance Aims to Help Keep Sprouts Contamination Free

By Food Safety Tech Staff
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Sprouts

Between 1996 and 2016, sprouts have been responsible to 46 outbreaks in the United States, which has led to nearly 2500 illnesses and three deaths, according to FDA. They have presented a consistent challenge to operators, because sprouts are most often produced in conditions that are ideal for bacteria growth.

Today FDA issued a draft guidance to assist sprout operators in complying with the FSMA Produce Rule, which requires “covered sprout operations take measures to prevent the introduction of dangerous microbes into seeds or beans used for sprouting, test spent sprout irrigation water (or, in some cases, in-process sprouts) for the presence of certain pathogens, test the growing, harvesting, packing and holding environment for the presence of the Listeria species or Listeria monocytogenes, and take corrective actions when needed.”

Large sprout operators must comply with the Produce Rule (applicable provisions) by January 26. Small business must comply by January 26, 2018 and very small businesses by January 28, 2019.

The draft guidance, Compliance with and Recommendations for Implementation of the Standards for the Growing, Harvesting, Packing, and Holding of Produce for Human Consumption for Sprout Operations, is open for comment for the next 180 days.

FDA

FDA Revises Draft Guidance for Listeria Control in RTE Foods

By Food Safety Tech Staff
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FDA

Any food facility that manufactures, processes, packs or holds ready-to-eat (RTE) foods should view FDA’s update on its draft guidance, Control of Listeria monocytogenes in Ready-To-Eat Foods. Consistent with FSMA, the draft focuses on prevention, and includes best practices and FSIS’s seek-and-destroy approach. Other recommendations include controls involving personnel, cleaning and maintenance of equipment, sanitation, treatments that kill Lm, and formulations that prevent Lm from growing during food storage (occurring between production and consumption).

“This guidance is not directed to processors of RTE foods that receive a listericidal control measure applied to the food in the final package, or applied to the food just prior to packaging in a system that adequately shields the product and food contact surfaces of the packaging from contamination from the food processing environment.” – FDA

The agency will begin accepting comments on January 17.

FSC 2016

FSMA, Listeria, Fraud and Food Safety Culture Among Top Topics at Food Safety Consortium

By Maria Fontanazza
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FSC 2016

The 2016 Food Safety Consortium was a big success, from the preconference events that included the STOP Foodborne Illness fundraiser honoring heroes in food safety and the education workshops (SQF Information Day and preventive controls courses) to the record-breaking attendance we saw during the main program (with keynotes from FDA Deputy Commissioner for Foods and Veterinary Medicine Stephen Ostroff, M.D., Walmart’s Vice President of Food Safety Frank Yiannas, and FBI’s Special Agent Scott Mahloch).

As the event winded down, the leaders of each session track shared their insights on lessons learned during the Consortium.

Understanding biofilm and how it forms.  If you’re seeing peaks and valleys in the positives and negatives in your environmental swabbing program, you may have resident Listeria that has formed a biofilm, which requires a deep clean. Focus on biofilm, not just mitigation of the Listeria bacteria itself. – Gina Kramer, Savour Food Safety International. Read Gina’s column, Food Safety Think Tank, where she talks about the latest technology and innovations.

This is the first conference I’ve been to you where food fraud is being more widely acknowledged as a serious, important concern that is distinctly separate from food safety. One of the more significant takeaways is the number of tools that are now available for people to mitigate their risk to food fraud in the supply chain. – Steve Sklare, USP

Warren Hojnacki, SGS
Warren Hojnacki, SGS

A while back food safety was a nice-to-have but not a need-to-have. It’s certainly an absolute need-to-have now. There are three groups of individuals out there: The third that has picked up the baton and is proactive, the other third that are in the middle of it right now, and the other third have their heads in the sand. I come across a sizable portion that is in the bottom third, and it’s slightly scary… It’s the documentation that a lot of companies are having the biggest challenge in dealing with—the death by paper. The resources out there are immense. It’s a necessity to have right now in order to be effective and compliant.  – Warren Hojnacki, SGS

FSMA regulations require us to be risk based, scientifically based and systematic in our approach to our concerns and issues. – Barb Hunt, Savour Food Safety International

There’s potential for greater data and actions: i.e., the microbiome study or particulate contamination analysis, PLM, IR spectroscopy, SEM EDS, [and] raman spectroscopy…Lab customers may need to depend more greatly on contract labs as FSMA develops and in return, labs need to work more closely with the customers to get dependable, defensive data results. – Eric Putnam, Wixon, Inc.

Trish Wester, PA Wester Consulting
Trish Wester, PA Wester Consulting

We need to do a better job of messaging upstream to our corporate senior officials so we get the money and resources we need—there’s still a gap there. We need to find ways to communicate to them.  – Trish Wester, PA Wester Consulting

Katy Jones, Foodlogiq
FST Soapbox

Mitigating Supply Chain Risk with Transparency and Traceability

By Katy Jones
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Katy Jones, Foodlogiq

Attend the Food Safety Supply Chain Conference, June 5–6, 2017 in Rockville, MD | LEARN MOREA recent study from The Hartman Group on the topic of transparency found that consumers are becoming more concerned about imports and the safety standards behind companies producing food and beverage products beyond U.S. borders.

So with the drastic rise in consumer expectations for food quality and safety in the past few years, how can companies ensure they’re mitigating risks in the supply chain while fostering transparency to meet consumer expectations?

To our benefit, the focus of the broader food industry and the government, as well as innovations in technology, are making it easier than ever to comprehensively track the supply chain.

Another Day, Another Food Recall, Another Listeria Scare

In today’s reality, whether we like it or not, food recalls are an inevitable part of the food industry, and adulteration in the supply chain is a key safety issue. With the wellbeing of consumers at stake, if a contamination finds its way into a brand’s supply chain, the best possible course of action is to take action on a recall using impeccable supply chain records and monitor the affected product moving throughout the chain.

With recalls being here to stay in the food industry, companies need to be prepared to handle these issues quickly and effectively. By implementing supplier management and whole-chain traceability software, allergens and impurities can be pinpointed to a specific lot of product as opposed to being limited to processing/issue date, and not knowing the source or country of origin of every ingredient (as many suppliers can contribute to one product) within the supply chain.

Additionally, with these technologies, brands can keep their supply chain transparent and compliant with growing industry regulations. With consumer standards on the line, proactive transparency can ensure that a company has a plan of attack when the inevitable hits.

A Targeted and Precise Plan

Companies and brands need to broaden their definition of food safety in order to manage and satisfy an expanded set of consumer expectations. The traditional, linear “one-up and one-back” (OUOB) approach to supply chain is no longer acceptable when it comes to comprehensive supply chain transparency.

Consumers need a targeted and precise plan when dealing with the safety of their food—it’s no longer just about whether the food safe to eat. The definition has expanded to include safety around ingredients and country of origin. Awareness of where a product came from and where it is going next is not an acceptable method if a company wishes to foster transparency with customers and effectively manage recalls. In addition, these standards are emphasized by federal regulations like the FSMA and FSVP—the industry is now shifting towards preventative approaches to safety matters, as opposed to reactive. FSMA requires food manufacturers to increase focus on prevention rather than response to contamination incidents, which will require a comprehensive view of the entire supply chain.

Brands will need to develop strong food safety plans with streamlined audits and compliance records, verifying supply chain partners and executing corrective actions for suppliers that are not in compliance with the process and food safety plan set in place. In establishing this process, having the technology to support it is paramount in ensuring that suppliers are sticking to the food safety practices necessary to follow industry regulation and exceed consumer expectation.

Transparency in Today’s Complex Food Paradigm

As the global food supply continues to grow in volume and complexity, brands have an opportunity and an obligation to adapt to the food paradigm. According to a Label Insight study, 94% of consumers say transparency from food brands is the #1 factor that impacts purchase. Brands are no longer able to blame a supplier’s lack of transparency or unreliable records for exposing consumers to unsafe products but instead, the brand is solely held accountable.

Transparency and proactivity were optional in the past, but are now established as fundamental components of a brand’s safety plan if they are to adapt to the changing industry landscape as well as consumer demand. As recalls are bound to happen, proactivity and transparency can ensure that a company is one step ahead of an outbreak at all times.

The fact is, adapting to this shifting environment and aligning with these best practices and the technologies that enable them is critical to the success of the supplier, distributor and across the whole supply chain. Food companies must look to utilize big data analytics and intelligent supply chain mapping technologies in order to improve transparency and increase traceability. With the ability to track ingredients back and forth across the supply chain, these technologies enable a safer consumer experience as well as provide tremendous business value in eliminating inefficiencies, managing supply chain issues, and effectively protecting the brand with the insights offered.

Pursuit of Clarity for WGS in Food Production Environments

By Joseph Heinzelmann
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Anyone who has attended a food safety conference in the last few years has experienced some type of whole genome sequencing (WGS) presentation. WGS is the next big thing for food safety. The technology has been adopted by regulatory agencies, academics, and some food companies. A lot has been said, but there are still some questions regarding the implementation and ramifications of WGS in the food processing environment.

There are a few key acronyms to understand the aspects of genomics in food safety (See Table I below).

PFGE Pulse Field Gel Electrophoresis Technique using restriction enzymes and DNA fragment separation via an electronic field for creation of a bacterial isolate DNA fingerprint; PFGE is being replaced by WGS at CDC and other public health laboratories
WGS Whole Genome Sequencing The general term used for sequencing—a misnomer—the entirety of the genome is not used, and depends on the analytical methodology implemented
NGS Next Generation Sequencing NGS is the next set of technology to do WGS and other genomic applications
SNP Single Nucleotide Polymorphisms A variation in a single nucleotide that occurs in specific position of an organism’s genome; Used in WGS as a methodology for determining genetic sameness between organisms
MLST Multilocus sequence typing A methodology for determining genetic sameness between organisms; Compares internal fragment DNA sequences from multiple housekeeping genes
16S 16s RNA sequencing A highly conserved region of the bacterial genome used for species and strain identification

Joseph Heinzelmann will be presenting: Listeria Testing Platforms: Old School Technology vs New Innovative Technology during the 2016 Food Safety Consortium | LEARN MOREIn 1996, the CDC established the PulseNet program for investigating potential foodborne illness outbreaks.  PulseNet has relied on using bacterial DNA fingerprints generated via PFGE as comparisons for mapping potential sources and spread of the outbreaks.  Due to a number of advantages over PFGE, WGS is quickly becoming the preferred method for organism identification and comparison. Moving to WGS has two critical improvements over PFGE: accuracy and relatedness interpretation. Like PFGE there are nuances when defining the difference between two very closely related organisms. However, instead of defining restriction enzymes and comparing the number of bands, the language changes to either single nucleotide polymorphisms (SNP) or the number of alleles. The other important aspect WGS improves is the ability to determine and interpret the relatedness of organisms more broadly. The frequent Listeria outbreaks and incidence from 1983-2015 provide an insight to what the future might hold with WGS implementation.1 The incidence report shows the increased ability to quickly and more accurately define relatedness between clinical cases creates a link of potential cases much faster.

WGS also provides key practical changes for outbreaks and recalls in the food industry. Sequencing provides a much faster response time and therefore means the outbreaks of foodborne illness decrease, as does the number of cases in each outbreak. As the resolution of the outbreaks increases, the number of outbreaks identified increases. The actual number of outbreaks has likely not increased, but the reported number of outbreaks will increase due increased resolution of the analytical method.

wgs_listeria
Figure 1: (Permission for use of slide from Patricia M. Griffin, M.D. – Center for Disease Control and Prevention)

WGS continues to establish itself as the go-to technology for the food safety agencies. For example, the USDA food safety inspection service recently published the FY2017–2021 goals. The first bullet point under modernizing inspection systems, policies and the use of scientific approaches is the implementation of in-field screening and whole genome sequencing for outbreak expediency.

Agencies and Adoption

The success of FDA and CDC Listeria project provides a foundation for implementation of WGS for outbreak investigations. The three agencies adopting WGS for outbreak investigations and as replacement for PulseNet are the CDC, FDA and USDA. However, there are still questions on the part of the FDA for when WGS is utilized, including under what circumstances and instances the data will be used.

In recent public forums, the FDA has acknowledged that there are situations when a recall would be a potential solution based on WGS results in the absence of any clinical cases.2 One critical question that still exists in spite of the public presentations and published articles is a clear definitions of when WGS surveillance data will be used for recall purposes, and what type of supporting documentation a facility would need to provide to prove that it had adequate controls in place.

A key element is the definition between agencies for sameness or genetic distance. The FDA and FSIS are using a SNP approach. A sequence is generated from a bacterial isolate, then compared with a known clinical case, or a suspected strain, and the number of different SNPs determines if the strains are identical. The CDC is using the Multilocus sequence typing (MLST) approach.

Simple sequence comparisons are unfortunately not alone sufficient for sameness determination, as various metabolic, taxa specific and environmental parameters must also be considered.  Stressful environments and growth rates have significant impact on how quickly SNPs can occur. The three primary pathogens being examined by WGS have very different genetic makeups. Listeria monocytogenes has a relatively conserved genomic taxa, typically associated with cooler environments, and is gram positive. Listeria monocytogenes has a doubling time of 45–60 minutes under enrichment conditions.3 These are contrasted with E. coli O157:H7, a gram negative bacteria, associated with higher growth rates and higher horizontal gene transfer mechanisms. For example, in an examination of E. coli O104, and in research conducted by the University in Madurai, it showed 38 horizontal gene elements.4

These two contrasting examples demonstrate the complexity of the genetic distance question. It demonstrates a need for specific definitions for sameness within a microbiological taxa, and with potential qualifiers based on the environment and potential genetic event triggers. The definitions around SNPs and alleles that define how closely related a Listeria monocytogenes in a cold facility should be vastly different from an E. coli from a warm environment, under more suitable growth conditions. Another element of interest, but largely unexplored is convergent evolution. In a given environment, with similar conditions, what is the probability of two different organisms converging on a nearly identical genome, and how long would it take?

MLST vs. SNP

As previously stated, the three agencies have chosen different approaches for the analytical methodology: MLST for CDC and SNP of the FDA and USDA. For clarity, both analytical approaches have demonstrated superiority over the incumbent PFGE mythology. MLST does rely on an existing database for allele comparison. A SNP based approach is supported by a database, but is often used in defining genetic distance specifically between two isolates. Both approaches can help build phylogenetic trees.

There are tradeoffs with both approaches. There is a higher requirement for processing and bioinformatics capabilities when using a SNP based approach. However, the resolution between organisms and large groups of organisms is meaningful using SNP comparison. The key take away is MLST uses a gene-to-gene comparison, and the SNP approach is gene agnostic. As mentioned in Table 1, both approaches do not use every A, T, C, and G in the analytical comparisons. Whole genome sequencing in this context is a misnomer, because not every gene is used in either analysis.

Commercial Applications

Utilizing WGS for companies as a preventive measure is still being developed. GenomeTrakr has been established as the data repository for sequenced isolates from the FDA, USDA, CDC and public health labs. The data is housed at the National Center for Biotechnology Information (NCBI).  The database contains more than 71,000 isolates and has been used in surveillance and outbreak investigations. There is a current gap between on premise bioinformatics and using GenomeTrakr.

The FDA has stated there are examples where isolates found in a processing facility would help support a recall in the absence of epidemiological evidence, and companies are waiting on clarification before adopting GenomeTrakr as a routine analysis tool. However, services like NeoSeek, a genomic test service by Neogen Corp. are an alternative to public gene databases like GenomeTrakr. In addition to trouble shooting events with WGS, NeoSeek provides services such as spoilage microorganism ID and source tracking, pathogen point source tracking. Using next generation sequencing, a private database, and applications such as 16s metagenomic analysis, phylogenetic tree generation, and identification programs with NeoSeek, companies can answer critical food safety and food quality questions.

References

  1. Carleton, H.A. and Gerner-Smidt, P. (2016). Whole-Genome Sequencing Is Taking over Foodborne Disease Surveillance. Microbe. Retrieved from https://www.cdc.gov/pulsenet/pdf/wgs-in-public-health-carleton-microbe-2016.pdf.
  2. Institute for Food Safety and Health. IFSH Whole Genome Sequencing for Food Safety Symposium. September 28­–30, 2016. Retrieved from https://www.ifsh.iit.edu/sites/ifsh/files/departments/ifsh/pdfs/wgs_symposium_agenda_071416.pdf.
  3. Jones, G.S. and D’Orazio, S.E.F. (2013). Listeria monocytogenes: Cultivation and Laboratory Maintenance. Curr Proto Microbiol. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3920655/.
  4. Inderscience Publishers. “Horizontal gene transfer in E. coli.” ScienceDaily, 19 May 2015.
  5. Gerner-Smidt, P. (2016). Public Health Food Safety Applications for Whole Genome Sequencing. 4th Asia-Pacific International Food Safety Conference. Retrieved from http://ilsisea-region.org/wp-content/uploads/sites/21/2016/10/Session-2_2-Peter-Gerner-Smidt.pdf.
Sabra hummus recall

Sabra Recalls Hummus Due to Possible Listeria Contamination

By Food Safety Tech Staff
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Sabra hummus recall

Don’t miss the Listeria Detection & Control Workshop at the 2016 Food Safety Consortium | December 7–8 | Schaumburg, IL | Learn MoreFDA has issued a consumer alert following the recall of Sabra Dipping Company’s hummus products. The agency began an inspection of Sabra’s manufacturing facility in Virginia on October 31, collecting nine environmental samples that test positive for Listeria monocytogenes; FDA collected 18 additional environmental samples near food handling equipment on November 18, which tested positive for Lm. It’s also possible that the strain of Lm found in the facility is persistent in the company’s production environment, according to FDA.

“One of the strains of Listeria monocytogenes found during the recent inspection matches a strain found in a retail product sample collected in 2015, indicating this strain of Listeria monocytogenes may be persistent in the production environment.” – FDA

Sabra initiated a voluntary recall of certain hummus products distributed in the United States and Canada with “Best Before” dates on or before January 23, 2017. “Subsequent to the inspection conducted with the FDA, we implemented a thorough and extensive factory-wide cleaning and sanitation procedure, and beyond that, we continue to work very closely with internal and external food safety experts to identify any additional steps we can take to even further enhance our efforts,” according to a Sabra press release.

Meritech Helps Companies Improve Employee Hygiene GMPs

Meritech, manufacturer of the world’s only fully-automated, touch-free handwashing systems will be exhibiting at the 2016 Food Safety Consortium in Schaumburg, Illinois — with one of its automated handwashers onsite for attendees to experience the technology-based approach to employee hand hygiene. Meritech offers a full line of automated handwashing and footwear sanitizing systems, designed to meet increasingly stringent food safety standards and regulations.

All CleanTech automated handwashing systems deliver a consistent 12-second wash and rinse cycle, removing 99.98% of dangerous pathogens from hands. Meritech products use 75% less water, require less soap/sanitizer, and reduce discharge waste, compared to equivalent manual handwashing.

Listeria and Salmonella outbreaks are some of the biggest fears throughout the food industry. Effective employee hygiene at critical control points is necessary and Meritech offers the best guaranteed preventative measures through its automated systems.  Effective, efficient footwear sanitizing, especially when  combined with simultaneous handwashing, can reduce or eliminate the spread of these and other pathogens. Meritech’s automated handwasher with an optional footwear sanitizing pan guarantees clean hands and sanitized shoes in 12 seconds.

Meritech helps companies in a wide variety of markets, including food production, food service, theme parks, cruise lines and hospitals. All Meritech products are designed and manufactured in Golden, Colorado. The company ensures that your equipment is always effective by delivering best-in-class, proprietary chemicals and providing no charge, onsite scheduled calibration by its team of Service Engineers. Visit www.meritech.com to learn more.

Recall

More Ice Cream Recalls Over Listeria Concerns

By Food Safety Tech Staff
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Recall

The 2016 Food Safety Consortium features a Listeria Detection & Control Workshop | Don’t miss this event two day event, December 7–8 in Schaumburg, IL | LEARN MOREOver the past few days there have been at least four recalls over Listeria concerns in ice cream products. On Monday, Blue Bell Ice Cream voluntarily recalled all of the products made with a cookie dough ingredient from one of its suppliers, Aspen Hills. “Although our products in the marketplace have passed our test and hold program, which requires that finished product samples from a batch test negative for Listeria monocytogenes before the batch can be released, Blue Bell is initiating this recall out of an abundance of caution,” according to a release on FDA’s website. Other recalls include:

Similar to the Blue Bell recall, the other two recalls involving cookie dough came from the ingredient supplied by Aspen Hills, Inc.

No illnesses have been reported.

Eliminating Listeria: Closing the Gap in Sanitation Programs

By Kevin Lorcheim
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Food production facilities are facing greater scrutiny from both the public and the government to provide safe foods. FSMA is being rolled out now, with new regulations in place for large corporations, and compliance deadlines for small businesses coming up quickly. Coverage of food recalls is growing in the era of social media. Large fines and legal prosecution for food safety issues is becoming more commonplace. Improved detection methods are finding more organisms than ever before. Technologies such as pulsed-field gel electrophoresis (PFGE) can be used to track organisms back to their source. PFGE essentially codes the DNA fingerprint of an organism. Using this technology, bacterial isolates can be recovered and compared between sick people, contaminated food, and the places where food is produced. Using the national laboratory network PulseNet, foodborne illness cases can be tracked back to the production facility or field where the contamination originated. With these newer technologies, it has been shown that some pathogens keep “coming back” to cause new outbreaks. In reality, it’s not that the same strain of microorganism came back, it’s that it was never fully eradicated from the facility in the first place. Advances in environmental monitoring and microbial sampling have brought to light the shortcomings of sanitation methods being used within the food industry. In order to keep up with the advances in environmental monitoring, sanitation programs must also evolve to mitigate the increased liability that FSMA is creating for food manufacturers.

Paul Lorcheim of ClorDiSys Solutions will be speaking on a panel of Listeria Detection & Control during the 2016 Food Safety Consortium, December 8 | LEARN MOREPersistent Bacteria

Bacteria and other microorganisms are able to survive long periods of time and become reintroduced to production facilities in a variety of ways. Sometimes construction or renovation within the facility causes contamination. In 2008, Malt-O-Meal recalled its unsweetened Puffed Rice and Puffed Wheat cereals after finding Salmonella Agona during routine testing of its production plant. Further testing confirmed that the Salmonella Agona found had the same PFGE pattern as an outbreak originating from the same facility 10 years earlier in 1998. This dormant period is one of the longest witnessed within the food industry. The Salmonella was found to be originating from the cement floor, which had been sealed over rather than fully eliminated. This strategy worked well until the contamination was forgotten and a renovation project required drilling into the floor. The construction agitated and released the pathogen back into the production area and eventually contaminated the cereal product. While accidental, the new food safety landscape looks to treat such recurring contaminations with harsher penalties.

One of the most discussed and documented cases of recurring contamination involves ConAgra’s Peter Pan peanut butter brand. In 2006 and 2007, batches of Peter Pan peanut butter produced in Sylvester, GA were contaminated with Salmonella and shipped out and sold to consumers nationwide. The resulting outbreak caused more than 700 reported cases of Salmonellosis with many more going unreported. Microbial sampling determined that the 2006 contamination resulted from the same strain of Salmonella Tennessee that was found in the plant and its finished product in 2004. While possible sources of the contamination were identified in 2004, the corrective actions were not all completed before the 2006–2007 outbreak occurred. Because of the circumstances surrounding the incomplete corrective actions, ConAgra was held liable for the contamination and outbreak. A settlement was reached in 2015, resulting in a guilty plea to charges of “the introduction into interstate commerce of adulterated food” and a $11.2 million penalty. The penalty included an $8 million criminal fine, which was the largest ever paid in a food safety case. While the problems at the Sylvester plant were more than just insufficient contamination control, the inability to fully eliminate Salmonella Tennessee from the facility after the 2004 outbreak directly led to the problems encountered in 2006 and beyond.

Many times, bacteria are able to survive simply because of limitations of the cleaning method utilized by the sanitation program. In order for any sanitation/decontamination method to work, every organism must be contacted by the chemical/agent, for the proper amount of time and at the correct concentration by an agent effective against that organism. Achieving those requirements is difficult for some sanitation methods and impossible for others. Common sanitation methods include steam, isopropyl alcohol, quaternary ammonium compounds, peracetic acids, bleach and ozone, all of which have a limited ability to reach all surfaces within a space, and some are incapable of killing all microorganisms.

Bacteria
Figure 1. Bacteria in a 10-micron wide scratch.

Liquids, fogs and mists all have difficulty achieving an even distribution throughout the area, with surfaces closer or easier to reach (i.e., the top or front of an item), receiving a higher dosage than surfaces further away or in hard-to-reach areas. Such hard-to-reach areas for common sanitation methods include the bottom, back or insides of items and equipment that don’t receive a “direct hit” from the decontaminant. Liquids, fogs and mists land on and stick to surfaces, which makes it harder for them to reach locations outside the line of sight from where they are injected or sprayed. Hard-to-reach areas also include ceilings, the tops of overhead piping lines, HVAC vents, cooling coils and other surfaces that are located at greater heights than the liquids, fogs and mists can reach due to gravitational effects on the heavy liquid and vapor molecules.

Another common but extreme hard-to-reach area includes any cracks and crevices within a facility. Although crevices are to be avoided within production facilities (and should be repaired if found), it is impossible to guarantee that there are no cracks or crevices within the production area at all. Liquid disinfectants and sterilant methods deal with surface tension, which prevents them from reaching deep into cracks. Vapor, mist and fog particles tend to clump together due to strong hydrogen bonding between molecules, which often leave them too large to fit into crevices. Figure 1 shows bacteria found in a scratch in a stainless steel surface after it had been wiped down with a liquid sterilant. The liquid sterilant was unable to reach into the scratch and kill/remove the bacteria. The bacteria were protected by the crevice created by the scratch, giving them a safe harbor location where they could replicate and potentially exit in the future to contaminate product itself.

Processing machinery
Figure 2. Processing machinery

Processing equipment and machinery in general contain many hard-to-reach areas, which challenge the routine cleaning process. In sanitation, “hard to reach” is synonymous with “hard to clean”. Figure 2 shows  processing equipment from an ice cream manufacturing facility. Processing equipment cannot be manufactured to eliminate all hard-to-clean areas. As such, even with all the sanitary design considerations possible, it is impossible to have equipment that does not contain any hard-to-clean areas. While sanitary design is essential, additional steps must be taken to further reduce the possibility of contamination and the risk that comes along with it. This means that in order to improve one’s contamination control and risk management programs, improvements must also be made to the sanitation program and the methods of cleaning and decontamination used.

Chlorine Dioxide Gas

Food safety attorney Shawn K. Stevens recently wrote that “given the risk created by the FDA’s war on pathogens, food companies should invest in technologies to better control pathogens in the food processing environments.”1 One method that is able to overcome the inherent difficulties of reaching all pathogens within a food processing environment is chlorine dioxide gas (ClO2 gas). ClO2 gas is a proven sterilant capable of eliminating all viruses, bacteria, fungi, and spores. As a true gas, ClO2 gas follows the natural gas laws, which state that it fills the space it is contained within evenly and completely. The chlorine dioxide molecule is smaller than the smallest viruses and bacteria. Combined, this means that ClO2 gas is able to contact all surfaces within a space and penetrate into cracks further than pathogens can, allowing for the complete decontamination of all microorganisms with the space. It also does not leave residues, making it safe for the treatment of food contact surfaces. It has been used to decontaminate a growing number of food facilities for both contamination response and contamination prevention in order to ensure sterility after renovations, equipment installations and routine plant shutdowns.

Conclusion

“If food companies do not take extraordinary measures to identify Lm in their facilities, perform a comprehensive investigation to find the root cause or source, and then destroy and eliminate it completely, the pathogen will likely persist and, over time, intermittently contaminate their finished products,” wrote Stevens.1  Environmental monitoring and sampling programs have been improved in terms of both technology and technique to better achieve the goal of identifying Lm or other pathogens within a food production environment. The FDA will be aggressive in its environmental monitoring and sampling under the food safety guidelines required by FSMA. Food production facilities will be closely monitored and tracked using PulseNet, with contaminated product being traced back to their source. Recurring contamination by a persistent pathogen will be viewed more severely. While there are many reasons that pathogens can persist within a food manufacturing environment, insufficient cleaning and decontamination is the most common. Traditional cleaning methods are incapable of reaching all surfaces and crevices within a space. In order to eliminate the risk of pathogens re-contaminating a facility, the pathogens need to be fully eliminated from their source and harbor locations. ClO2  gas is a method capable of delivering guaranteed elimination of all pathogens to maintain a pathogen-free environment. With the new era of food safety upon us, ensuring a clean food production environment is more important than ever, and ClO2 gas is uniquely situated to help reduce the risk and liability provided by both the government and the public.

In the summer of 2015, multiple ice cream manufacturers were affected by Listeria monocytogenes contamination. Part two of this article will detail one such company that utilized ClO2 gas to eliminate Listeria from its facility.

Reference

  1. Stevens, S.K. (June 3, 2016). “Find Contamination, Reduce Pathogens, and Decrease Criminal Liability”. Retrieved from https://foodsafetytech.com/column/find-contamination-reduce-pathogens-decrease-criminal-liability/