Tag Archives: Testing

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Advances in GC-MS/MS Enhance Routine Detection of Dioxins and Dioxin-like Compounds in Food and Animal Feed

By Richard Law
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Dioxins are highly toxic organic compounds that can remain in the environment for extended periods. These persistent organic pollutants (POPs), which include polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), are mainly generated by the combustion or manufacture of chlorine-containing materials such as plastics. Dioxins and other closely related POPs, such as polychlorinated biphenyls (PCBs), are classed as carcinogenic by the United States Environmental Protection Agency, and present a significant threat to human health even at low levels.

Dioxins and PCBs can enter the food chain when livestock consume contaminated animal feed, and can accumulate in the fatty tissues of animals due to their high fat-solubility. As a result, over 90% of human exposure to dioxins and PCBs is through the consumption of meat, fish, dairy and other foods of animal origin.1 Given the health risks posed by dioxins and PCBs, effective food testing workflows are essential to ensure products do not exceed regulatory-defined safe levels.

GC-MS/MS: A Robust Technique for Analyzing Dioxins and PCBs in Food and Animal Feed

To control human exposure to PCDDs, PCDFs and PCBs from the food chain, global regulatory bodies have established maximum levels (MLs) and action levels (ALs) for various POPs in food products, as well as approved analytical methods for food testing laboratories to enforce these standards. In the European Union (EU), for example, European Commission regulations 2017/644 and 2017/771 outline sampling, sample preparation and analysis protocols for the detection of dioxins and other dioxin-like compounds in food and animal feedstuffs.2,3

With food testing laboratories tasked with handling potentially hundreds of samples every day, these workflows must be supported by robust and reliable analytical technologies that can confidently identify and accurately quantify dioxins and PCBs with minimal maintenance requirements in order to minimize downtime and maximize throughput.

Thanks to ongoing improvements in the robustness and sensitivity of gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) systems, regulations were updated in 2014 to permit this technique as an alternative to gas chromatography-high resolution mass spectrometry (GC-HRMS) for confirmatory analysis and for the control of MLs and ALs. The latest GC-MS/MS systems are capable of exceptionally reliable performance for the routine analysis of dioxins and PCBs, providing accurate and sensitive quantification of these compounds even at trace levels.

Case Study: Sensitive and Reliable Determination of Dioxins Using GC-MS/MS

The performance of modern GC-MS/MS systems was evaluated in a recent study involving the confirmatory analysis and quantification of 17 PCDDs and PCDFs, and 18 dioxin-like and non-dioxin-like PCBs in solvent standards and various food and feedstuff samples. The samples were analyzed using a triple quadrupole GC-MS/MS system equipped with the advanced electron ionization source (AEI) and a TG-Dioxin capillary GC column. Two identical GC-MS/MS systems in two separate laboratories were used to assess the reproducibility of the method.

Extraction was performed by Twisselmann hot extraction or pressurized liquid extraction. The automated clean-up of the extracts was performed using a three-column setup, comprising multi-layered acidic silica, alumina and carbon columns. Two fractions were generated per sample (the first containing non-ortho PCBs, PCDDs and PCDFs, and the second containing mono-ortho and di-ortho PCBs and indicator PCBs) and these were analyzed separately. The analytical method gave excellent separation of all the PCDD, PCDF and PCB congeners in less than 45 minutes.

Given the high sensitivity of modern GC-MS/MS instruments, a calibration-based approach was used to determine limits of quantitation (LOQs) of the analytical system. Using calibration standards at the LOQ and subsequent check standards at this level enabled the performance of the method to be assessed throughout the analytical sequence. This also allowed LOQs for the individual congeners to be determined, assuming a fixed sample weight. Individual congener LOQs could be applied to upper-bound, middle-bound and lower-bound toxicity equivalence (TEQ) results by substituting the result of any congener that fell below the lowest calibration point with this value multiplied by the toxicity equivalence factor (TEF) of the congener.

To evaluate the response factor deviation over the course of the analytical sequences, standards at the specified LOQ were analyzed at the start, during and end of each run. Using a nominal weight of 2 g, and assuming 100% 13C-labeled standard recovery and all natives were less than the LOQ in the sample, a minimum upper-bound value of 0.152 pg/g WHO-PCDD/F-TEQ was determined. This met regulatory requirements for reporting at 1/5th of the ML upper-bound sum TEQ for all food and feedstuffs with a nominal intake of 2 g, with the exception of guidance associated with liver of terrestrial animals and food for infants or young children, which both have legal limits defined on a fresh weight basis. In these cases, either a larger sample intake or a magnetic sector instrument would be required. All of the calibration sequences demonstrated response factor %RSDs within EU regulations, highlighting the suitability of the method.

To demonstrate the performance of the GC-MS/MS system, six replicate extractions of a mixed fat quality control sample (QK1) were prepared, split between the two sites and analyzed at regular intervals throughout the analytical sequences (14 injections in total). The measured WHO-PCDD/F-TEQ values for congener were in excellent agreement with the reference value provided by the EU Reference Laboratory for Halogenated POPs in Feed and Food, and the upper bound WHO-PCDD/F-TEQ value did not deviate by more than 6% from the reference value for all 14 measurements (Figure 1). The deviation between the upper-bound and lower-bound WHO-PCDD/F-TEQ for each measurement was consistently less than 1.2%, well below the maximum limit of 20% necessary to support compliance with EU regulations.

pper- and lower-bound WHO-PCDD/F-TEQ values
Figure 1. Upper- and lower-bound WHO-PCDD/F-TEQ values for all 14 measurements of the QK1 mixed animal fat quality control sample, for six replicate extractions.

Robust Routine Analysis of Dioxin and Dioxin-like Compounds

To assess the robustness of the GC-MS/MS system, the PCDD, PCDF and non-ortho PCB extracts were pooled into a mixed matrix sample and analyzed more than 161 injection sequences across a period of approximately two weeks. Each sequence consisted of 40 matrix injections and 40 LOQ standards, interspersed with nonane blanks. No system maintenance, tuning or user intervention was undertaken throughout the two-week study. Figure 2 highlights the exceptional peak area stability achieved for selected PCDD and PCDF congeners.

Peak area repeatability
Figure 2. Absolute peak area repeatability over two weeks of analysis for selected PCDD and PCDF congeners in a pooled matrix sample (%RSD and amounts on column are shown for each congener).

These results highlight the exceptional levels of day-to-day measurement repeatability offered by the latest GC-MS/MS systems. By delivering consistently high performance without the need for extensive maintenance steps, modern GC-MS/MS systems are maximizing instrument uptime and increasing sample throughput for routine POP analysis workflows.

Conclusion

Developments in GC-MS/MS technology, namely the advanced electron ionization source, are pushing the limits of measurement sensitivity, repeatability and robustness to support the needs of routine dioxin and PCBs analysis in food and feed samples. By minimizing instrument downtime while maintaining exceptional levels of analytical performance, these advanced systems are helping high-throughput food testing laboratories to analyze more samples and ultimately better protect consumers from these harmful pollutants.

References

  1. Malisch, R. and Kotz, A. (2014) Dioxins and PCBs in feed and food – Review from European perspective. Sci Total Environ, 491, 2-10.
  2. European Commission. Commission Regulation (EU) 2017/644, Off J Eur Union, 2017, L92 9-34.
  3. European Commission. Commission Regulation (EU) 2017/771, Off J Eur Union, 2017, L115 22-42.

Acknowledgements

This article is based on research by Richard Law and Cristian Cojocariu (Thermo Fisher Scientific, Runcorn, UK), Alexander Schaechtele (EU Reference Laboratory for Halogenated POPs in Feed and Food, Freiburg, Germany), Amit Gujar (Thermo Fisher Scientific, Austin, US), and Jiangtao Xing (Thermo Fisher Scientific, Beijing, China).

Managing Microbiological Testing as a Preventive Control Verification

FDA’s final rule “Current Good Manufacturing Practice, Hazard Analysis, and Risk-Based Preventive Controls for Human Food” requires that preventive controls be verified to ensure that they are consistently and effectively implemented. Who Should Attend: Anyone involved in food safety or quality assurance, including preventive control qualified individuals, retailers, consultants, educators, students, and government professionals.

2019 Food Safety Consortium Conference & Expo

Mark Your Calendars: 2019 Food Safety Consortium Includes Panels on Recalls, Food Defense and Supply Chain Transparency

By Maria Fontanazza
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2019 Food Safety Consortium Conference & Expo

The 2019 Food Safety Consortium Conference & Expo kicks off on Tuesday, October 1 and is packed with two-and-a-half days of informative sessions on a variety of topics that are critical to the food safety industry. We invite you to check out the full agenda on the event website, but below are several event highlights that you should plan on attending.

  • Opening Keynote: Frank Yiannas, Deputy Commissioner for Food Policy and Response, FDA
  • Recalls Panel Discussion: Led by Rob Mommsen, Director of Global Quality & Food Safety, Sabra Dipping Company
  • Food Defense Panel: Led by Steven Sklare, REHS, CP-FS, LEHP. Invited Panelists include Jason P. Bashura, MPH, RS, Sr. Mgr., Global Food Defense, PepsiCo and Jill Hoffman, Director, Global Quality Systems and Food Safety at McCormick & Company and Clint Fairow, M.S. Global Food Defense Manager, Archer Daniels Midland Company
  • “Validation Considerations and Regulations for Processing Technologies”: General Session presented by Glenn Black, Ph.D., Associate Director for Research, Division of Food Processing Science and Technology (DFPST), Office of Food Safety (OFS), CFSAN, FDA
  • “Food Safety Leadership: Earning respect – real-life examples of earning and maintaining influence as a Food Safety leader”: Panel Discussion moderated by Bob Pudlock, President, Gulf Stream Search
  • Supply Chain Transparency Panel Discussion: Led by Jeanne Duckett of Avery Dennison
  • Taking an Aggressive Approach to Sanitation: Planning for a Contamination Event: Presented by Elise Forward, President, Forward Food Safety
  • Three Breakout Tracks: Food Safety Leadership; Food Testing & Analysis and Sanitation and Operations

Register by September 13, 2019 for a special discount!

Frank Yiannas, VP of Food Safety, Walmart
Watch this video from when Frank Yiannas was the vice president of food safety at Walmart. He presented at the 2015 Food Safety Consortium.

Steven Sklare, USP, Aaron Biros, Food Safety Tech
Watch this video of Steven Sklare speaking with Aaron Biros of Cannabis Industry Journal at the 2017 Food Safety Consortium.

Bob Pudlock, Gulf Stream Search
Read Bob Pudlock’s exclusive series on Food Safety Tech, Architect the Perfect Food Safety Team.

Elise Forward, Forward Food Solutions
Elise Forward discusses how to take food defense beyond the four walls of your business.
Emily Kaufman, Emport, Allergens
Allergen Alley

Skip Validation, You’re Asking for Problems

By Emily Kaufman
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Emily Kaufman, Emport, Allergens

Running an unvalidated program or product is like betting your life’s savings on a horse because you overheard a “surefire tip” outside the racetrack, or driving around without any mirrors.

To put it less dramatically: Skipping validation is asking for problems. But what does validation mean, how much is necessary, and what’s the best way to include it in your plans?

In order to start understanding validation, we must first break it down into two main categories: Product validation and process validation. From there, it’s important to look at whether something has been broadly validated for general use, and whether it has been narrowly validated for use in your specific situation. That last question is where people often struggle: How can we ensure this product or process is validated for use in the way that we plan to use it?

Validating an on-site allergen test kit requires a few different layers of research and testing. Taking the time to carefully design and vet a validation process may seem tedious, and it may require some additional up-front costs—but in the long run, it’s the only way to ensure you are spending your money on a test kit that works. And if you’re using an allergen test kit that doesn’t actually detect allergens in your facility—best-case scenario, you’re wasting money and time. Worst-case scenario, you’re headed straight for a recall and you won’t see it coming until your customers get sick.

If you are buying a test to determine the absence or presence of allergens in your facility (specific or general), you’ll likely ask the kit manufacturer if the test kit has been validated. This validation can come in many forms, most commonly:

  • Third party validation (eg., AOAC)
  • Internally produced validation documents or whitepapers
  • Published studies

A product with more validation (third-party certifications, studies, whitepapers) isn’t necessarily better than a product with less. It may have simply been on the market longer or be produced by a company that allocates its funding differently. However, validation documents can be very comforting when reviewing a product, as they provide a starting point for your own research. When you are reviewing validation data, ask yourself a few questions:

  • Does this data cover products like mine?
    • Are the ingredients similar (raw meat, ice cream, spices, etc.)?
    • Are the preparation processes similar (heat, fermentation, etc.)?
  • Does this data cover an environment like mine?
    • Will the tests be run the same way in my facility as in the data?
    • Is the contamination being introduced in a way and amount that feels realistic to the risk factors I know about in my facility?
  • Does the data mention any complicating factors (and do I need to care about them)?
    • Are there ingredients known to cross-react or cause false negatives?
    • Are there processes known to change the LOD or cause false negatives?
  • If I am aware of limitations with other similar test kits, are those limitations addressed in the data for this test kit as well?

To give an example, let’s imagine you make premium ice cream and are reviewing allergen test kits that look for peanuts and almonds in product, in rinsewater and on surfaces. You’ll want to ask questions like:

  • How does the kit perform in a high-fat environment?
  • Does the validation data cover product, rinsewater and surfaces?
  • Are there ingredients in our facility that are called out as cross-reactive (or otherwise troublesome)?
  • Do our ingredients get exposed to temperatures, pH levels, or other processes that impact the LOD?

You might learn, for example, that one of the matrices tested in validation was ice cream. If so: Wonderful! That’s a vote of confidence and a great starting point. Or maybe you learn that the kit in question isn’t recommended for matrices that include an ingredient in your formulation. If so: That’s equally wonderful! Now you know you need a different solution. Or maybe the instructions on your current peanut test kit indicate that heavily roasted peanuts have a higher detection limit than raw peanuts, but this new test kit only has data for raw peanuts. If so: OK! You have more research to do, and that’s fine too.

In short: Pre-existing product validation data is a helpful starting point for determining whether or not an allergen test kit MIGHT work well in your facility—but it doesn’t eliminate the need for you to run your own internal validation study.

Once you’ve identified an allergen test kit that you want to use in your facility, you’ll want to prove that it can work to identify contamination in your specific environment. This is where a more narrowly tailored validation comes into play. Your test kit provider may have resources available to help you design an internal validation. Don’t be afraid to ask for help! A reputable test kit provider should care not just about making the sale, but also about making your food safer.

Before you even order a new test kit, you should have a good idea of how your validation process is going to work. It’s important to have both the study design and study outcome on file. Here are some possible additions for your internal validation study:

Validating that an allergen test kit can reliably prove your surfaces are clean of said allergen:

  • Test the surface prior to cleaning, after the allergen in question has been run. Do you see positive results? If not, then a negative result after cleaning is essentially meaningless.
  • Test the surface after cleaning. Do you see negative results? If not, it could mean a problem with your cleaning process—or a strange interference. Both require further research.
  • If your products encounter multiple surfaces (eg., stainless steel and also ceramic), test them all with before and after testing.

Validating that an allergen test kit can reliably prove your rinsewater is free of said allergen:

  • Test water from the beginning of the cleaning cycle as well as the end. Do you see a change in results, from positive to negative?
  • If you don’t ever see the allergen present in your rinsewater, you may want to “spike” a sample by adding a small amount of the product that contains the allergen into the rinsewater you’ve collected. Could it be that something in your cleaning protocol or some aspect of your matrix is affecting the detection limit?

Validating that an allergen test kit can reliably prove your ingredients or finished products are free of said allergen:

  • Test a product that you know contains the allergen but is otherwise similar. Keep in mind that some allergen test kits can be overloaded and can show false negatives if too much allergen is present in the sample—if you aren’t sure whether the test kit you are trialing has this limitation, ask your supplier. Do you see a positive?
  • Have you encountered batches of your product with accidental cross-contamination from the allergen in question? If so, and you have some of that batch archived, run a test on it. Would this kit have identified the problem?
  • Do you have a batch or lot of product that has been analyzed by a third-party lab? If so, do your results in-house match the lab’s results?
  • Run—or ask a lab to run—a spiked recovery. This is especially important if there is no pre-existing data on how the test kit works against your specific matrices.
    • Some test kit manufacturers can provide this service for you—you would simply need to send them the product, and they can add various amounts of allergen into the product and confirm that the test kit shows positive results.
    • Some kit manufacturers or other suppliers can send you standards that have known quantities of allergen in them. You can mix these into your product and run tests, and confirm that you get positive results when expected.
    • You may want to simply do this on your own, by adding small quantities of the allergen into the sample and running tests. However, take care to be especially careful with your documentation in case questions arise down the line.
  • No matter how the spiked recovery is being run, consider these two factors:
    • Be sure you’re including what could be a realistic amount of contamination—if you’re concerned about catching 25ppm of allergen, loading up your sample with 2000ppm won’t necessarily help you prove anything.
    • The matrix of your allergen-containing foods is just as important as the matrix of your allergen-free foods. If your allergen has been fermented, roasted, pressurized, etc. —your spike needs to be processed in the same way. If you aren’t sure how to think about your matrices, this previous Allergen Alley post is a good starting place.

Once you’ve proven that the test kit in question can in fact show positive results when traces of allergen are present, you can confidently and comfortably incorporate it into your larger allergen control plan. If your matrices change, you’ll want to re-validate whatever’s new.

While it can be tempting to rely on a kit’s general validation, taking the extra step to validate your unique matrices is an essential part of a truly robust food safety plan. If you’re stumped for how to begin, contact your kit provider—after all, you share the same goals: Safe, allergen-free food for consumers who rely on you to keep themselves and their families healthy and well fed.

AOAC International

AOAC Sinks Teeth into Cannabis Testing, Launches Food Fraud Program

By Food Safety Tech Staff
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AOAC International

Last week Cannabis Industry Journal, a sister publication of Food Safety Tech, published its interview with AOAC International officials about the organization’s commitment to cannabis lab testing, where it sees this area headed in the future and the launch of its food authenticity and fraud program. AOAC first entered the realm of cannabis testing a few years ago and is making strides to get further involved with “methods regarding chemical contaminants in cannabis, cannabinoids in various foods and consumables, as well as microbial organisms in cannabis,” according to the article. AOAS also recently launched a food authenticity and fraud program to develop standards and methods geared toward economically adulterated foods. Read more about AOAC’s latest development on the food front as well as its push in cannabis lab testing in the article, “Spotlight on AOAC: New Leadership, New Initiatives in Cannabis and Food”.

Food Safety Consortium - October 1-3, 2019 - Schaumburg, IL

Industry Experts Darin Detwiler and Randy Phebus Join Food Safety Consortium Conference & Expo Advisory Board

By Food Safety Tech Staff
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Food Safety Consortium - October 1-3, 2019 - Schaumburg, IL

EDGARTOWN, MA, Feb. 19, 2019 – Innovative Publishing Co., the publisher of Food Safety Tech and organizer of the Food Safety Consortium Conference & Expo has added two distinguished industry leaders to its Advisory Board for this year’s Consortium event, which takes place October 1–3. Randall Phebus, Ph.D., interim director at the Food Science Institute and professor of food safety & defense at Kansas State University, will serve as chairperson for the Testing track at the Food Safety Consortium Conference & Expo, and Darin Detwiler, lead faculty for regulatory affairs of food and food industry, and assistant teaching professor at Northeastern University, will chair the Food Safety Leadership and Management track. Detwiler and Phebus will have a significant role in organizing these tracks to ensure that the sessions are accurate, relevant and meaningful for attendees.

“The addition of Darin Detwiler and Randy Phebus to the Food Safety Consortium Conference & Expo Advisory Board is an important step in further expanding the wealth of expertise brought to this annual event,” said Rick Biros, president of Innovative Publishing Co., Inc. and director of the Food Safety Consortium Conference and Expo. “Darin and Randy are highly respected professionals in this industry, and I am delighted to work with them and to help deliver their insights to Consortium attendees.”

2018 Food Safety Supply Chain Conference, Blockchain
A dynamic panel about blockchain, led by Darin Detwiler, Director: Regulatory Affairs of Food and Food Industry, Northeastern University at the 2018 Food Safety Supply Chain Conference

Detwiler has been a member of the Food Safety Tech and Food Safety Consortium Advisory Board for two years and has made strong contributions to the content at the organization’s events, including most recently leading panel discussions on blockchain at last year’s Food Safety Supply Chain Conference and the 2018 Food Safety Consortium. Phebus is joining the Advisory Board for 2019 and will be providing critical perspectives in the area of food microbiology, food safety testing and environmental control.

Detwiler and Phebus join Angela Anandappa, Ph.D., who was announced as the chairperson for the 2019 Food Safety Consortium Conference & Expo’s Sanitation track.

About Food Safety Tech

Food Safety Tech publishes news, technology, trends, regulations, and expert opinions on food safety, food quality, food business and food sustainability. We also offer educational, career advancement and networking opportunities to the global food industry. This information exchange is facilitated through ePublishing, digital and live events.

About the Food Safety Consortium Conference and Expo

The Food Safety Consortium Conference and Expo is a premier educational and networking event for food safety solutions. Attracting the most influential minds in food safety, the Consortium enables attendees to engage conversations that are critical for advancing careers and organizations alike. Visit with exhibitors to learn about cutting edge solutions, explore diverse educational tracks for learning valuable industry trends, and network with industry executives to find solutions to improve quality, efficiency and cost effectiveness in an ever-changing, global food safety market. This year’s event takes place October 1–3 in Schaumburg, IL.

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FDA Report on E. Coli Outbreak in Romaine Lettuce Points to “Significant” Finding of Strain in Sediment of Water Reservoir

By Maria Fontanazza
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The November 2018 outbreak of E.coli O157:H7 infections linked to romaine lettuce caused 62 illnesses across 16 states. The FDA zeroed in on the Central Coast growing regions of northern and Central California as being responsible for the contamination. The outbreak was declared over on January 9 and yesterday FDA released the report, “Factors Potentially Contributing to the Contamination of Romaine Lettuce Implicated in the Fall 2018 Multi-State Outbreak of E.Coli O157:H7”, which provides an overview of the investigation.

The report states that a sediment sample coming from an on-farm water reservoir in Santa Maria (Santa Barbara County, California) tested positive for the outbreak strain of E. coli O157:H7. Although this particular farm was identified in several legs of the Fall 2018 traceback investigations that occurred in the United States and Canada, as well as being a possible supplier of romaine lettuce in the 2017 traceback investigations, the FDA said that the farm is not the single source of the outbreak, as there is “insufficient evidence”. The traceback suggests that the contaminated lettuce could have come from several farms, because not all tracebacks led to the farm on which the contaminated sediment was found.

“The finding of the outbreak strain in the sediment of the water reservoir is significant, as studies have shown that generic E. coli can survive in sediments much longer than in the overlying water. It’s possible that the outbreak strain may have been present in the on-farm water reservoir for some months or even years before the investigation team collected the positive sample. It is also possible that the outbreak strain may have been repeatedly introduced into the reservoir from an unknown source,” stated FDA Commissioner Scott Gottlieb, M.D. and Deputy Commissioner Frank Yiannas in a press announcement.

(left to right) Stic Harris, FDA; Matt Wise, CDC; Dan Sutton, Pismo Oceano Vegetable Exchange; Scott Horsfall, California Leafy Greens Marketing Agreement discuss the first E.coli outbreak involving romaine lettuce during a panel at the 2018 Food Safety Consortium. Read the article about the discussion.

Although the exact route of contamination cannot be confirmed, the FDA hypothesizes that it could have occurred through the use of agricultural water from an open reservoir, which has increased potential for contamination.

The investigation teams also found evidence of “extensive” wild animal activity and animal burrows near the contaminated reservoir, as well as adjacent land use for animal grazing, all of which could have contributed to the contamination.

Although FDA did not directly name the farm in the report, it provided a link about the recall that was initiated by the farm, Adam Bros. Farming, Inc., in December.

Considering the significant effect that the past two E.coli outbreaks involving romaine lettuce have had on both the public as well as the produce industry, FDA made several recommendations on preventive measures that leafy greens growers and industry can take to avoid such pathogenic contamination, including:

For growers:

  • Assessing growing operations to ensure they are in line with compliance to FSMA and good agricultural practices
  • Making sure that any agricultural water that comes into direct contact with the harvestable portion of the crop, food contact surfaces and harvest equipment is safe and sanitary
  • Address and mitigate risks associated with agricultural water contamination that can occur as a result of intrusion by wild animals
  • Address and mitigate risks associated with the use of land near or adjacent to agricultural water sources that can lead to contamination
  • Conduct root cause analysis whenever a foodborne pathogen is identified in the growing environment, agricultural inputs like water or soil, raw agricultural commodities, or “fresh-cut” ready-to-eat produce

For the broader industry:

  • The development of real-time procedures that enable rapid examination of the potential scope, source and route of contamination
  • All leafy green products should have the ability to be traced back to the source in real time, and information include harvest date. In November, FDA requested voluntary labeling [https://foodsafetytech.com/news_article/cdc-alert-do-not-eat-romaine-lettuce-throw-it-out/] to help consumers identify products affected during an outbreak
  • The adoption of best practices in supply chain traceability

Resources

  1. FDA report: “Factors Potentially Contributing to the Contamination of Romaine Lettuce Implicated in the Fall 2018 Multi-State Outbreak of E.Coli O157:H7”
  2. FDA statement from Commissioner Scott Gottlieb, M.D. and Deputy Commissioner Frank Yiannas
  3.  FDA investigation of source of E.coli O157:H7 outbreak linked to romaine lettuce
Emily Kaufman, Emport, Allergens
Allergen Alley

Matrix Matters: Why Allergen Test Kits Are Only Half the Story

By Emily Kaufman
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Emily Kaufman, Emport, Allergens

On-site rapid tests for allergens are an important part of any manufacturing facility’s allergen control plan. Several companies offer allergen test kits for day-to-day use, and it can be hard to tell the differences between them or determine which is the best fit for a given facility. What’s a busy QA professional to do?

One of the most overlooked factors when choosing an allergen test kit actually has almost nothing to do with the test kit itself. Instead, it’s much closer to home: The matrices being tested are just as—if not more—important to consider than the test kit itself.

Before you commit to any allergen test kit, you should talk to someone extensively about the types of products you plan to test. There are a variety of surprising and counterintuitive ways that your matrices can impact the functionality of a test, and you’ll save time and money by understanding information BEFORE you start testing. Below, we’ll review some of the most common matrix challenges.

High Fat Matrices

fruit pops, allergensLet’s imagine a facility that makes ice cream and sorbet. Let’s assume they make a gourmet strawberry ice cream and a fat-free strawberry sorbet, both of which ought to be peanut-free—but since some of the ingredients come from a supplier who also works with peanuts, the QA team decides to run a rapid peanut test on the strawberry products.

Much to the team’s surprise, the sorbet tests positive for peanut but the ice cream does not. What could be happening? Of course, the simplest explanation is possible: The sorbet has peanut residue in it and the ice cream does not. However, there’s another, trickier possibility: They could have the same amount of peanut residue, but the full-fat ice cream could inhibit the test kit’s ability to detect the allergen.

In general, the higher the fat content of your matrices, the higher the detection limit on your test kit. It’s an imprecise spectrum: Using rapid tests to find traces of allergenic protein on an oil is nearly impossible, on fat-rich items like ice cream or cream-based soups it’s a challenge, on items with little or no fat it shouldn’t be an issue. That isn’t to say there couldn’t be other issues with low-fat items, as we’ll review below.

Matrices Processed with High Heat

peanuts, allergensLet’s say our ice cream facility starts making a peanut-butter-swirl flavor. Perhaps they will begin testing their rinsewater for peanut residue after running that flavor, to ensure satisfactory cleaning. The kit they use says it can detect peanut allergen to 5 ppm, and rinsewater is not a high-fat matrix, so they should be good, right?

In this exact example, it’s probably just fine. However, it’s important for the QA team to consider the temperature at which peanuts were roasted. While raw peanut might be detectable at 5 ppm, roasted peanuts could have a detection limit that is much higher. In fact, very strongly roasted peanuts could only be detectable at levels of 500 ppm or more. This doesn’t mean there is no reason to test—but it’s important to know that many antibody-based tests will respond differently to an allergen processed with high heat than one that is raw. The same detection challenge can sometimes be seen with canned or tinned items that are subjected to high heat in processing.

Fermented or Hydrolyzed Matrices

Two of the trickiest items when it comes to allergen detection are soy sauce and fish sauce. In both of these condiments—and many other common ingredients subjected to these types of processing—the allergenic material is subjected to heavy modification. As proteins get folded and broken in unpredictable ways, they become more challenging for antibody-based test kits to detect. In fact, soy sauce and fish sauce are nearly undetectable by most kits.

When validating a cleaning process after using one of these ingredients, often the safest thing to do is to test for a different allergen—formulated in a simpler way—that is also present. Sufficient cleaning after a product made with fish sauce and breadcrumbs, for example, could be proven with a gluten kit; that second allergen will be unaffected by the fermented allergens in the recipe.

Matrices without Multiple Proteins

Some kits look for a variety of proteins commonly found within one allergen. Other times, though, each test kit will be looking for one specific protein. It’s important to confirm that the allergenic protein your facility works with is in fact an allergenic protein that your test kit is trained to recognize.

Perhaps the most common FALCPA allergen where this plays a role is milk. While there are a number of proteins in milk, casein is the most common and accounts for approximately 80% of the protein in milk, making it a common target for allergen test kits (both rapid and ELISA). The remaining 20% of protein is comprised of various whey proteins, most commonly beta-lactoglobulin.

In the case of our ice cream and sorbet facility mentioned above, a kit that detects casein OR beta-lactoglobulin OR both proteins together could be suitable for confirming that the sorbet is truly milk-free. However, there are other types of product that contain only whey proteins, which are a popular way to increase protein content in a variety of foods and beverages. If a facility that works exclusively with whey proteins uses a kit that only detects casein, they will never have a true understanding of their allergen contamination risk.

Another challenging FALCPA allergen is fish, as there are many different species of fish with quite divergent protein structures. If you are testing for fish contamination, it’s important to understand which species of fish the test you are considering can detect, and which species may pose a problem. If there is a mismatch between kit and matrix, then you’ll need to find a different way to ensure safety.

How to Troubleshoot Your Matrices

If you are beginning an allergen testing program, find time to talk with the manufacturers of any allergen kits you are considering. You may also want to talk with the representatives of any labs that are doing third party testing for you. Some questions to ask include:

  • What matrices have you validated your tests for?
  • Do you anticipate any issues with my matrices?
  • How should I validate your tests for my products?
  • What factors impact the sensitivity of this kit?
  • Does the detection limit change based on the matrix?

Your kit manufacturer (or third-party testing lab) should make you feel confident that they understand the quirks of your specific matrices—and they should have ideas for how to troubleshoot any challenges that they foresee. If a supplier tells you that their kit will work equally well across all matrices and declines to offer proof that corresponds to your needs, beware (or at least be prepared to conduct rigorous validation on your own). Allergen detection is complicated, and as with so much of life: If it sounds too good to be true, it probably is.

Gabriela Lopez, 3M Food Safety
Allergen Alley

Method Acting: Comparing Different Analytical Methods for Allergen Testing and Verification

By Gabriela Lopez-Velasco, Ph.D.
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Gabriela Lopez, 3M Food Safety

Every day, food industries around the world work to comply with the food labeling directives and regulations in place to inform consumers about specific ingredients added to finished products. Of course, special attention has been placed on ensuring that product packaging clearly declares the presence of food allergens including milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, soy, sesame and mustard. (Additional food allergens may also be included in other regions.)

But labeling only covers the ingredients deliberately added to foods and beverages. In reality, food manufacturers have two jobs when it comes to serving the needs of their allergic consumers:

  1. Fully understand and clearly declare the intentional presence of allergenic foods
  2. Prevent the unintended presence of allergenic foods into their product

Almost half of food recalls are the result of undeclared allergens, and often these at-fault allergens were not only undeclared but unintended. Given such, the unintended presence of allergenic foods is something that must be carefully considered when establishing an allergen control plan for a food processing facility.

How? It starts with a risk assessment process that evaluates the likelihood of unintentionally present allergens that could originate from raw materials, cross-contact contamination in equipment or tools, transport and more. Once the risks are identified, risk management strategies should then be established to control allergens in the processing plant environment.
It is necessary to validate these risk management strategies or procedures in order to demonstrate their effectiveness. After validation, those strategies or procedures should then be periodically verified to show that the allergen control plan in place is continually effective.

In several of these verification procedures it may be necessary to utilize an analytical test to determine the presence or absence of an allergenic food or to quantify its level, if present. Indeed, selecting an appropriate method to assess the presence or the level of an allergenic food is vitally important, as the information provided by the selected method will inform crucial decisions about the safety of an ingredient, equipment or product that is to be released for commercialization.

A cursory review of available methods can be daunting. There are several emerging methods and technologies for this application, including mass spectroscopy, surface plasmon resonance, biosensors and polymerase chain reaction (PCR). Each of these methods have made advancements, and some of them are already commercialized for food testing applications. However, for practical means, we will discuss those methods that are most commonly used in the food industry.

In general, there are two types of analytical methods used to determine the presence of allergenic foods: Specific and non-specific methods.

Specific tests

Specific methods can detect target proteins in foods that contain the allergenic portion of the food sample. These include immunoassays, in which specific antibodies can recognize and bind to target proteins. The format of these assays can be quantitative, such as an enzyme-linked immunosorbent assay (ELISA) that may help determine the concentration of target proteins in a food sample. Or they can be qualitative, such as a lateral flow device, which within a few minutes and with minimum sample preparation can display whether a target protein is or is not present. (Note: Some commercial formats of ELISA are also designed to obtain a qualitative result.)

To date, ELISA assays have become a method of choice for detection and quantification of proteins from food allergens by regulatory entities and inspection agencies. For the food industry, ELISA can also be used to test raw ingredients and final food products. In addition, ELISA is a valuable analytical tool to determine the concentration of proteins from allergenic foods during a cleaning validation process, as some commercial assay suppliers offer methods to determine the concentration of target proteins from swabs utilized to collect environmental samples, clean-in-place (CIP) final rinse water or purge materials utilized during dry cleaning.

ELISA methods often require the use of laboratory equipment and technical skills to be implemented. Rapid-specific methods such as immunoassays with a lateral flow format also allow detection of target specific proteins. Given their minimal sample preparation and short time-to-result, they are valuable tools for cleaning validation and routine cleaning verification, with the advantage of having a similar sensitivity to the lowest limit of quantification of an ELISA assay.

The use of a specific rapid immunoassay provides a presence/absence result that determines whether equipment, surfaces or utensils have been cleaned to a point where proteins from allergenic foods are indiscernible at a certain limit of detection. Thus, equipment can be used to process a product that should not contain a food allergen. Some commercial rapid immunoassays offer protocols to use this type of test in raw materials and final product. This allows food producers to analyze foods and ingredients for the absence of a food allergen with minimum laboratory infrastructure and enables in-house testing of this type of sample. This feature may be a useful rapid verification tool to analyze final product that has been processed shortly after the first production run following an equipment cleaning.

Non-Specific Tests

While non-specific testing isn’t typically the best option for a cleaning validation study, these tests may be used for routine cleaning verification. Examples of non-specific tests include total protein or ATP tests.

Tests that determine total protein are often based on a colorimetric reaction. For example, commercial products utilize a swab format that, after being used to survey a defined area, is placed in a solution that will result in a color change if protein is detected. The rationale is that if protein is not detected, it may be assumed that proteins from allergenic foods were removed during cleaning. However, when total protein is utilized for routine verification, it is important to consider that the sensitivity of protein swabs may differ from the sensitivity of specific immunoassays. Consequently, highly sensitive protein swabs should be selected when feasible.

ATP swab tests are also commonly utilized by the food industry as a non-specific tool for hygiene monitoring and cleaning verification. However, the correlation between ATP and protein is not always consistent. Because the ATP present in living somatic cells varies with the food type, ATP should not be considered as a direct marker to assess the removal of allergenic food residues after cleaning. Instead, an analytical test designed for the detection of proteins should be used alongside ATP swabs to assess hygiene and to assess removal of allergenic foods.

Factors for Using One Test Versus Another

For routine testing, the choice of using a specific or a non-specific analytical method will depend on various factors including the type of product, the number of allergenic ingredients utilized for one production line, whether a quantitative result is required for a particular sample or final product, and, possibly, the budget that is available for testing. In any case, it is important that when performing a cleaning validation study, the method used for routine testing also be included to demonstrate that it will effectively reflect the presence of an allergenic food residue.

Specific rapid methods for verification are preferable because they enable direct monitoring of the undesirable presence of allergenic foods. For example, they can be utilized in conjunction with a non-specific protein swab and, based on the sampling plan, specific tests can then be used periodically (weekly) for sites identified as high-risk because they may be harder to clean than other surfaces. In addition, non-specific protein swabs can be used after every production changeover for all sites previously defined in a sampling plan. These and any other scenarios should be discussed while developing an allergen control plan, and the advantages and risks of selecting any method(s) should be evaluated.

As with all analytical methods, commercial suppliers will perform validation of the methods they offer to ensure the method is suitable for testing a particular analyte. However, given the great diversity of food products, different sanitizers and chemicals used in the food industry, and the various processes to which a food is subjected during manufacturing, it is unlikely that commercial methods have been exhaustively tested. Thus, it is always important to ensure that the method is fit-for-purpose and to verify that it will recover or detect the allergen residues of interest at a defined level.

Maria Fontanazza, Douglas Marshall, Eurofins, Food Safety Tech, Food Safety Consortium

Eurofins Expands Pacific Northwest Services with Acquisition of Cascade Analytical

By Food Safety Tech Staff
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Maria Fontanazza, Douglas Marshall, Eurofins, Food Safety Tech, Food Safety Consortium

Eurofins customers in the Pacific Northwest region will now be able to join expanded services in Washington State. The company has taken its offerings to a new level with the acquisition of Cascade Analytical, delivering a more rapid turnaround time for customers located in the regions served by the towns of Yakima and Wenatchee in Washington (the state’s central valley). “This is an area where we have many customers, but we haven’t been able to serve them nearly to the level that we can now by having a laboratory presence there,” said Douglas Marshall, Ph.D., chief scientific officer at Eurofins during an exclusive interview with Food Safety Tech at the 2018 Food Safety Consortium. Marshall shares his thoughts in the following video.