Tag Archives: inspection

Sayed M Naim Khalid
FST Soapbox

Food Safety: The Responsibilities of Government vs. The Private Sector

By Sayed M Naim Khalid
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Sayed M Naim Khalid

The role of government oversight versus private efforts in ensuring food safety is a comparatively new topic. Recent cases, including the hefty fines against Family Dollar for major violations in relation to sanitary conditions, highlight the importance of strong safeguards. But a key question lingers: Would a shift from government inspections to private audits truly benefit both businesses and consumers?

Government food safety inspections have traditionally operated on a risk-based model, aiming to identify and mitigate potential hazards in food production facilities. However, recent incidents such as the Family Dollar case raise concerns about the adequacy of government oversight. Did the absence of high-risk products at Family Dollar prompt less frequent inspections, leaving the facility unchecked for sanitation and safety standards? And what about past outbreaks like the 2009 Salmonella outbreak linked to the Peanut Corporation of America’s products or the subsequent recalls of Wright County/Hillandale Farms Eggs in 2010 and Cargill Ground Turkey in 2011? Weren’t these crises preventable with proper oversight?

It is evident that failures in both business management and government oversight contribute to lapses in food safety. While businesses are responsible for maintaining proper hygiene, temperature control, and product quality, government agencies play a crucial role in enforcement and inspection. The delay in detecting issues, whether due to resource constraints or bureaucratic inefficiencies, can have dire consequences for consumers and tarnish the reputation of businesses.

Consumers, too, play a pivotal role in the food safety equation. While cost often influences purchasing decisions, an increasing awareness of food safety issues has prompted many to prioritize product quality and trustworthiness. However, consumer vigilance alone cannot substitute for robust regulatory oversight and industry compliance.

The Value of Private Sector Audits

Private sector food safety audits offer a complementary approach to government inspections, providing businesses with standardized frameworks for assessment and improvement. Certifications from reputable third-party organizations such as the Global Food Safety Initiative (GFSI) can enhance consumer trust and facilitate market access. However, private audits should not serve as a replacement for government inspections. While they offer valuable insights, they lack the regulatory authority and enforcement capabilities of government agencies.

The crux of the issue lies in resource allocation and prioritization. Adequate funding for government food safety inspection departments at the federal, state, and local levels is essential to ensure timely and thorough oversight. Proactive inspections, coupled with stringent enforcement measures, can prevent crises before they escalate, ultimately saving businesses and consumers from costly repercussions.

Moreover, fostering a robust food safety culture requires collaboration and accountability across the entire supply chain. From farm to fork, stakeholders must adhere to best practices, comply with regulations, and uphold ethical standards. This includes not only businesses but also government agencies, industry associations, and consumers themselves.

The transition from government food safety inspections to private sector audits should not be viewed as a binary choice but as a symbiotic relationship. While private audits offer valuable insights and incentives for improvement, they cannot replace the regulatory authority and enforcement capabilities of government agencies. A balanced approach, characterized by proactive government oversight, industry compliance, and consumer awareness, is essential to safeguarding public health and ensuring the success of businesses in the food industry.

Kiwa Group Acquires ASI Food Safety

By Food Safety Tech Staff
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Global Testing, Inspection and Certification (TIC) company Kiwa has acquired St. Louis-based ASI. ASI has provided farm-to-fork food safety solutions since the 1940s. The company offers a full suite of safety and quality services to the food and beverage, dietary supplements and cannabis industries. The merger will strengthen Kiwa’s U.S. footprint in providing Food, Feed & Farm certifications.

“Kiwa and ASI share similar customer-first business values and follow the same business model when it comes to testing, inspection and certification. By joining the Kiwa family, we’re combining their wide portfolio of accreditations and services (BRC, IFS, FSSC, PrimusGFS, GLOBALG.A.P., Rainforest Alliance, MSC/ASC, Organic/USDA and many others), global business network and expertise with our client network in farm-to-fork food safety to assist our growing client base in North America even better,” said Charray Williams, CEO of ASI.

On January 1, 2023, 29-year-old Tyler Williams, CTO of ASI, will take the reigns as CEO of ASI. He is the youngest CEO in the history of the company. He will succeed current CEO Charray Williams and lead the expansion of Kiwa and ASI in the Food, Feed & Farm sector in North America. Richard Stolk, Kiwa’s global Director for the Food, Feed & Farm sector will serve as President of the Board of ASI and will be directly involved in the further growth of ASI.

“Kiwa already has a strong footprint in the global Food, Feed & Farm sector. With ASI, we significantly expand our reach, expertise and footprint, particularly in the U.S. but certainly with a global perspective. Now that we have welcomed ASI to the Kiwa family, we can better provide our customers with a one-stop shop for food- and feed-related certification services on all continents,” said Stolk.

 

Recall

E. Coli Found in Ground Beef, More than 120,000 Pounds Recalled

By Food Safety Tech Staff
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Recall

New Jersey-based Lakeside Refrigerated Services is recalling about 120,872 pounds of ground beef products that may be contaminated with E. coli O103. The issue was uncovered during routine FSIS testing of imported products.

The recall affects ground beef products that were produced between February 1, 2022 and April 8, 2022, and have the establishment number EST. 46841” inside the USDA mark of inspection (FSIS has provided a full list of products and product codes as well as product labels). The products were distributed to retail locations nationwide.

Thus far there are no confirmed reports of illness or adverse reactions related to products affected by this recall. “Many clinical laboratories do not test for non-O157 Shiga toxin-producing E. coli (STEC) such as O103 because it is harder to identify than STEC O157:H7. People can become ill from STECs 2–8 days (average of 3–4 days) after consuming the organism,” FSIS stated in an announcement. The agency has advised that consumers throw out or return the recalled products to the place of purchase.

Alert

Family Dollar Recall Highlights Need for Sound Pest Management Plan

By Food Safety Tech Staff
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Alert

After finding evidence of rodent infestation during an inspection of a Family Dollar distribution facility in Arkansas, the FDA warned the public of usage and consumption of products purchased at certain stores from January 1 through present time. The affected products, which include food, were distributed to Family Dollar stores in Alabama, Arkansas, Louisiana, Mississippi, Missouri and Tennessee.

“Families rely on stores like Family Dollar for products such as food and medicine. They deserve products that are safe,” said Associate Commissioner for Regulatory Affairs, FDA, Judith McMeekin, Pharm.D. in an agency press release. “No one should be subjected to products stored in the kind of unacceptable conditions that we found in this Family Dollar distribution facility. These conditions appear to be violations of federal law that could put families’ health at risk. We will continue to work to protect consumers.”

The FDA inspection followed a consumer complaint and found both live and dead rodents, rodent feces and urine, and evidence of rodent presence, along with dead birds and bird droppings, throughout the facility in West Memphis, Arkansas. After fumigating the facility, 1100 dead rodents were recovered. FDA’s review of company records also revealed a history of infestation, with more than 2300 rodents collected between March 29 and September 17, 2021.

Among the range of hazards associated with rodents include Salmonella.

Family Dollar, Inc. initiated a voluntary recall of the FDA-regulated products that were stored and shipped from the infested facility. The company states that it is unaware of any reports of illnesses related to the recall.

COVID-19 has not slowed down pests, and the last thing a company needs is a failed audit due to preventable pest issues.

 

Alert

FDA Tells Consumers to Throw out Certain Powdered Infant Formulas due to Contamination

By Food Safety Tech Staff
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Alert

–UPDATE–March 14, 2022 — In an agency update, the FDA stated that it has removed the Salmonella Newport illness that was previously noted in the investigation. “In the early stages of this investigation, FDA included all consumer complaints of illness with exposure to products from the Sturgis, MI, facility. After further investigation, the FDA has determined that there is not enough information to definitively link this illness to powdered infant formula. CDC confirmed that this single Salmonella illness is not linked to an outbreak. The FDA and CDC are continuing to monitor for Salmonella cases and consumer complaints that may be related to this incident,” the FDA stated.

–END UPDATE–

Earlier this week Abbott issued a recall of infant powdered formulas (including Similac, Alimentum and EleCare) that were manufactured at the company’s Sturgis, Michigan plant. The company received consumer complaints in infants who had consumed powdered infant formula manufactured in this facility—specifically, three reports of Cronobacter sakazakii and one report of Salmonella Newport. All cases resulted in hospitalization, and one death was reported.

FDA began onsite inspection at the facility and thus far has found several positive Cronobacter results from environmental samples and reported adverse inspectional observations. “A review of the firm’s internal records also indicate environmental contamination with Cronobacter sakazakii and the firm’s destruction of product due to the presence of Cronobacter,” FDA stated in a CFSAN update.

The recalled Similac, Alimentum and EleCare products can be identified by their 7-to-9 digit code and expiration date:

  • First two digits of the code are 22 through 37 and
  • Code on the container contains K8, SH, or Z2, and
  • Expiration date of 4-1-2022 (APR 2022) or later.

In a company announcement published on FDA’s website, Abbott stated, during testing in our Sturgis, Mich., facility, we found evidence of Cronobacter sakazakii in the plant in non-product contact areas. We found no evidence of Salmonella Newport. This investigation is ongoing.” It added that “no distributed product has tested positive for the presence of either of these bacteria” but that the company will continue to conduct testing.

Parents and caregivers can find out whether the product they have is included in the recall by visiting the Similac recall website.

Recall

Q2 Food Recalls Increase 20%, Undeclared Allergens and Quality Top Cause

By Food Safety Tech Staff
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Recall

For the 23rd quarter in a row, undeclared allergens were the top cause of food recalls and accounted for 45% of them in Q3 2021, according to Sedgwick’s latest Recall Index report. Within allergens, undeclared milk was the leading cause and prepared foods remained the leading category.

“Companies need to concentrate on the basics through the second half of 2021 and final emergence from the COVID-19 pandemic,” the report states. “Amid supply chain pressures, high consumer demand and worker health and safety concerns arising from the coronavirus, food businesses are rightfully focused on their ability to maintain and conduct their core operations in safe manner while delivering quality, safe products to customers.”

FDA Recalls: Notable Numbers (Q2 2021)

  • 106 recalls affecting 7.9 million units
  • 5.8 million units (nearly 69%) impacted by recalls were due to one nut recall
  • 19 recalls were a result of quality issues
  • 18 recalls were a result of foreign material contamination
  • 11 recalls were a result of bacterial contamination—6 from Listeria; 4 Salmonella; and 1 E. coli

USDA Recalls: Notable Numbers (Q2 2021)

  • Recalls increased from 10 (Q1) to 12, but numbers still low compared to 2019 quarterly averages
  • Units impacted dramatically dropped nearly 83% to 207,322 units
  • Undeclared allergens were top cause of recalls, accounting for nearly 42%
    • Soy milk and eggs were main allergens, but first recall of food products due to sesame also occurred
  • Other recall reasons were quality (2), lack of inspection (2), bacterial contamination (2) and foreign material contamination (1)
  • Beef products (93,551 pounds) most impacted category, followed by fish (46,804 pounds)

The report also pointed out that heavy metal regulation will have increased emphasis, as FDA has made it a priority as a result of a report released by Congress earlier this year indicating the presence of dangerous toxic heavy metals found in baby foods.

Chris Keith, FlexXray
FST Soapbox

How Foreign Material Inspection Can Impact Your Liability From Packaging

By Chris Keith
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Chris Keith, FlexXray

Packaging is an essential component of our modern, global food supply. While it helps us preserve and protect food and creates instant brand recognition for consumers, packaging also inserts an additional level of necessary risk mitigation into the manufacturing process. Liability stemming from packaging is a serious concern for food manufacturers of all sizes, with millions of dollars and brand-damaging lawsuits on the line. Processed foods need packaging to arrive in the hands of consumers, and processed foods are necessary to feed the world’s population. According to a survey conducted by the United States National Library of Medicine, “60% of calories consumed were from ultra-processed foods.”1 This shows the prevalence of processed foods and the significant impact packaging, a ubiquitous component of processed foods, plays in the food industry.1 However, if not handled properly, food packaging can be a significant liability.

Liability from packaging commonly presents in two ways: First, as foreign material contamination. Broken, damaged or defective packaging material can end up in food products, which increases the risk of a consumer attempting to consume contaminated goods. Second, packaging can be a hurdle to effective remediation of foreign material contamination, as goods can often not be efficiently or effectively inspected back through in-plant critical control points. The resulting disposal of product can contribute to food and environmental waste, as well as lost profits.

The harsh truth is that if manufacturers lack processes to identify, prevent or mitigate foreign material contamination when it occurs in packaged food, packaging can be a significant liability at every stage from the manufacturing facility to the store shelf. Following strict food safety plans can save countless hours, resources and dollars in the long run.2

Foreign Material Contamination: Where It Comes From

Foreign material contamination comes from multiple sources in the production cycle. It can come from raw materials, like animal bones ending up in boneless meat products. It can happen during the production process when a screw or seal detaches from a machine and gets mixed into a pie. It can be biological, like an insect ending up in a bag of chips. Or it can come from packaging: A shard of glass winding up in a jar of salsa or a plastic wrapper finding itself in a muffin. All of these foreign material contaminants are risks and dangers for which manufacturers can be held liable.

Packaging-related contamination is a high priority for manufacturers. Foreign material contamination due to packaging occurs when contaminants like metal, plastic, styrofoam and other objects end up where they do not belong, disrupting the integrity and quality of the product. Packaging materials can break down into tiny pieces that inline inspection machines may not be able to identify. Inline machines are calibrated for a certain size and certain types of foreign material contamination, which may not include packaging materials. Additionally, inline machines are often used at critical points during the manufacturing process but are not commonly used to inspect completed packaged products.

Break It Down: Liabilities Within Food Packaging

The party most affected by missed foreign material contamination is the consumer. Current consumer trends point to greater ingredient awareness, education and research into the companies from which consumers purchase products. The consumer mindset of environmentally friendly products and socially responsible purchases are impacting the food industry directly. Consumers seek transparency from brands about the products they’re ingesting. When a consumer discovers foreign material contamination inside a product, it creates frustration and eliminates trust. In addition to negatively impacted brand reputation, a foreign object from packaging can be incredibly costly. Recalls, especially those that require a local or national public warning, are detrimental to a brand’s reputation.3 Consumer trust in a brand is priceless and can take years to repair when broken.

In the age of social media, consumer reports of foreign material contamination can spread like wildfire across multiple platforms, reaching countless consumers across the world. One tweet about a contaminated product can go viral, costing corporations their reputations or worse–– lawsuits. An accidental miss somewhere along the production line can result in public outrage and cost the manufacturer millions of dollars in wasted product and crisis management. Suppose a consumer accidentally consumes a foreign contaminant from product packaging which results in injury. In that case, the manufacturer could be held liable for the medical bills and even long-term care if the injury is debilitating. These court cases can be highly costly monetarily and in terms of public perception.

In addition to legal liability from consumers, the loss of product for foreign material contamination is typically very costly when labor, storage, time, materials and lost revenue are taken into account. A producer who makes the moral and ethical decision to dispose of product that may be contaminated loses money doing so. They also risk harming their reputation with consumers by contributing to the problem of food waste.

In the 21st century, shoppers are increasingly looking “beyond the label,” and are concerned with the impact their purchase behaviors have on the environment.4 Consumers in younger demographics are significantly more likely to have a purchase decision influenced by a company’s impact on and concern for the environment. Packaging is a major concern for food manufacturers as they seek to lessen their environmental impact to meet market demands. This impacts foreign material contamination in two important ways. First, as packaging materials move towards the use of biodegradable materials, the capability of technology to detect the difference between packaging and food material must increase. Second, environmentally-friendly packaging is still relatively new compared to traditional materials, and the risks of foreign material contamination associated with these materials are still relatively unknown.

Manufacturers are in a difficult position when dealing with the liabilities stemming from packaging as a foreign material contaminant. Compounding this issue is the role packaging plays in preventing manufacturers from using in-house processes or inline equipment to inspect product back through Critical Control Points. Inline mechanisms for identifying foreign material contamination are not designed to inspect completed, packaged product. If producers dispose of and rework product, they risk harm to sustainability-focused brands, production quotas and bottom lines. If they attempt to identify the contamination themselves, they lose valuable production time and potentially lose perishable product to spoilage. With nearly every solution, another liability arises.

Packaging Contaminants: Prevention, Response and Liability

The FDA-required Hazard Analysis and Critical Control Points (HACCP) plan has seven principles to ensure manufacturers meet food safety goals from production to consumption. Physical, chemical and visual tests are involved to ensure foreign contaminants do not exist in products produced in the manufacturing facilities.5 The more detailed processes are in place, the more protected companies are from recalls and reducing the chance of a lawsuit where the manufacturer is liable. Implementing different programs and processes to prevent and diminish food waste ultimately positively impacts the manufacturer’s bottom line. The Business Case conducted a study called “Reducing Food Loss, and Waste” that found “99% of companies earned a positive investment when they implemented programs to reduce food waste”.6

Many companies engage third-party food inspection partners as an extra measure to ensure that their product is free from foreign material contamination. By electing to utilize third-party inspection services, manufacturers hit a trifecta: They can typically salvage the majority of on-hold product, reduce food waste, and with the right partner, get the data they need to have traceability of foreign material contamination issues at their plant.

Manufacturers should pursue third-party inspection partners that meet a high standard of excellence. The best third-party inspection partners use cutting-edge technology to inspect products in higher detail than inline machines. Their machines should be capable of identifying foreign material contaminants of all types and have a high capacity to turn around large volumes of product efficiently. Their machines should be capable of overcoming the obstacle of packaging as an impediment to inspection using machines with a larger aperture than typical inline tools. Lastly, third-party inspection adds significant value if it has the ability to find and retrieve foreign material contamination so manufacturers can effectively use the resulting data to identify and remediate problems within the plant. An inspection service that does not meet these criteria is not an inspection service, but merely a method for outsourcing the same practices that a manufacturer would conduct in-house.

Liability Questions Answered

So, when are companies liable for packaging issues? Unfortunately, the answer isn’t always black and white. FSMA is in place to help prevent foodborne illness, requiring Food Safety Plans. In addition, the FDA recognizes “that ensuring the safety of the food supply is a shared responsibility among many different points in the global supply chain for both human and animal food,” so manufacturers may not be the only ones liable in many cases.7 The problem arises when manufacturers miss foreign contaminants or if foreign biological contaminants affect the integrity of the packaging.

Even if companies take the necessary steps, incorporate a HACCP plan and are vigilant, contamination can, unfortunately, happen at any time to any manufacturer. Using a third-party partner as an outside resource for foreign material inspection is important. Choosing a third-party partner with the experience, certifications, technology, processes and reputation to protect your brand is critical. Manufacturers can validate their internal processes and data using reports from their third-party inspection partner more quickly than they could internally.

Food packaging and the potential liability involved can be daunting. Still, with proper processes and procedures in place, manufacturers can have confidence that their products are hitting the shelves with a low probability of recall or lawsuit due to a packaging issue. While there is always a chance of foreign material contamination, quality packaging materials, quality assurance processes and quality third-party inspection partners can significantly reduce a company’s potential liability.

References

  1. Baraldi, L. G. (March 9, 2018). “Consumption of ultra-processed foods and associated sociodemographic factors in the USA between 2007 and 2012: evidence from a nationally representative cross-sectional study.” BMJ Open.
  2. FDA. “FSMA Final Rule For Preventive Controls For Human Food”.
  3. Lusk, J. (October 15, 2019). “Consumer Beliefs About Healthy Foods And Diets.”
  4. Cheung, K. H. J. L. (2020). “Meet the 2020 Consumers Driving Change“. IBM.
  5. FDA(August 14, 1997). “HACCP Principles & Application Guidelines.”
  6. Hansen, C. “The Business Case For Reducing Food Loss and Waste.” Champions 12.3.
  7. FDA. “Food Safety Modernization Act (FSMA).
Susanne Kuehne, Decernis
Food Fraud Quick Bites

Don’t Let The Cat(fish) Out Of The Bag

By Susanne Kuehne
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Susanne Kuehne, Decernis
Catfish, food fraud
Find records of fraud such as those discussed in this column and more in the Food Fraud Database. Image credit: Susanne Kuehne

A multinational criminal smuggling ring was involved in the import of mislabeled siluriformes fish, including several species of catfish, into the United States. Import of such fish is prohibited to ensure the safety of the food supply in the United States. The smuggled catfish was labeled and listed on the import paperwork as other types of fish, which was discovered during a customs inspection. Subsequent seizures of shipping containers and warehouses led to the discovery of large amounts of mislabeled fish. The defendants face steep prison sentences.

Resources

  1. White, C. (February 22, 2021). “Catfish smuggling ring busted in New York City”. Seafood Source.
  2. “Four Alleged Smugglers Charged For Importing Banned Catfish Into The United States”. (February 18, 2021). U.S. Department of Justice. U.S. Attorney’s Southern District of New York.
Olga Pawluczyk, P&P Optica
FST Soapbox

Assessing Detection Systems to Make Food Safer

By Olga Pawluczyk
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Olga Pawluczyk, P&P Optica

It is an exciting time to be in the food industry. Consumers are ever more aware of what they are eating and more demanding of quality. And the vital need to reduce global food waste is transforming how we produce and consume food. This is driving innovation all the way along the supply chain, from gate to plate.

One of the biggest areas of opportunity for the industry to increase automation and improve food safety is in the processing plant. The challenges processors have faced in the last 12 months have accelerated the focus on optimizing resources and the drive for more adoption of new technology.

Foreign material contamination is a growing issue in the meat industry and new types of detection systems are emerging to help address this challenge. As Casey Gallimore, director of regulatory and scientific affairs at the North American Meat Institute, highlighted in a recent webinar, 2019 was a record year for the number of recalls related to foreign object contamination, which totaled 27% of all FSIS recalls in that year.

“There are a number of potential reasons why recalls due to foreign object contamination have increased over the years: Greater regulatory focus, more discerning consumers, [and] more automation in plants. But one important reason for this trend is that we have a lot of new technology to help detect more, [but] we are not necessarily using it to its full potential,” said Gallimore. “As an industry, we have a strong track record of working together to provide industry-wide solutions to industry-wide problems. And I believe that education is key to understanding how different detection systems—often used together—can increase the safety and quality of our food.”

Types of Detection Systems

Processors use many different detection systems to find foreign materials in their products. Equipment such as x-rays and metal detectors, which have been used for many years, are not effective against many of today’s contaminants: Plastics, rubber, cardboard and glass. And even the most well trained inspectors are affected by fatigue, distraction, discomfort and many other factors. A multi-hurdle approach is imperative, and new technologies like vision systems need to be considered.

Vision systems, such as cameras, multi-spectral, and hyperspectral imaging systems can find objects, such as low-density plastics, that may have been missed by other detection methods. Yet, depending on the system, their performance and capabilities can vary widely.

Camera-based systems are the most similar to the human eye. These systems are good for distinguishing objects of varying size and shape, albeit in two-dimensions rather than three. But they become less effective in situations with low contrast between the background and the object being detected. Clear plastics are a good example of this.

Multi-spectral systems are able to see more colors, including wavelengths outside of the visible spectrum. However, multispectral systems are set up to use only specific wavelengths, which are selected based on the materials that the system is expected to detect. That means that multispectral systems can identify some chemical as well as visual properties of materials, based on those specific wavelengths. It also means that other materials, which the system has not been designed to find, will likely not be detected by a multispectral system.

Another relatively new type of vision system uses hyperspectral imaging. These systems use chemistry to detect differences in the materials being inspected and therefore recognize a broad range of different contaminants. They are especially good at seeing objects that cameras or human inspectors may miss and at identifying the specific contaminant that’s been detected. The same system can assess quality metrics such as composition and identify product flaws such as woody breast in chicken. Hyperspectral systems also gather tremendous amounts of chemistry data about the products they are monitoring and can use artificial intelligence and machine learning to get a more holistic picture of what is happening in the plant over time, and how to prevent future contamination issues. This might include identifying issues with a specific supplier, training or other process challenges on one line (or in one shift), or machinery in the plant that is causing ongoing contamination problems.

Many processors are considering implementing new inspection systems, and are struggling to understand how to compare the expected performance of different systems. One relatively simple methodology that can be used to evaluate system performance is, despite its simplicity, called a “Confusion Matrix”.

The Confusion Matrix

A confusion matrix is often used in machine learning. It compares the expected outcome of an event with the actual outcome in order to understand the reliability of a test.

Figure 1 shows four possible outcomes for any kind of test.

Actual (True Condition)

Predicted

(Measured Outcome)

Positive (P) Negative (N)
Positive Detection True Positives (TP) False Positives (FP)
Negative Detection False Negatives (FN) True Negatives (TN)
P = TP + FN N = FP + TN
Figure 1. Confusion Matrix

But what does a confusion matrix tell us, and how can it help us assess a detection system?

The matrix shows us that a detection system may incorrectly register a positive or negative detection event—known as a ‘False Positive’ or ‘False Negative’.

As an example, say we are testing for a disease such as COVID-19. We want to know how often our system will give us a True Positive (detecting COVID when it *IS* present) versus a False Positive (detecting COVID when it *IS NOT* present).

Let’s apply this to processing. If you are using an x-ray to detect foreign objects, a small piece of plastic or wood would pass through unnoticed. This is a False Negative. By contrast, a system that uses hyperspectral imaging would easily identify that same piece of plastic or wood, because it has a different chemical signature from the product you’re processing. This is a True Positive.

A high rate of false negatives—failing to identify existing foreign materials—can mean contaminated product ends up in the hands of consumers.

The other side of the coin is false positives, meaning that the detector believes foreign material to be present when in fact it is not. A high rate of False Positives can lead to significant and unnecessary product wastage, or in time lost investigating an incident that didn’t actually occur (see Figure 2).

True Positives and False Positives
Figure 2. Balance of True Positives and False Positives

The secret to a good detection system lies in carefully balancing the rates of true positives and false positives by adjusting the sensitivity of a system.

This is where testing comes in. By adjusting a system and testing under different conditions, and then plotting these outcomes on the confusion matrix, you get an accurate picture of the system’s performance.

Effectiveness of a Detector

Detection is not just the act of seeing. It is the act of making a decision based on what you have seen, by understanding whether something of importance has occurred. Many factors influence the effectiveness of any detection system.

Resolution. This is the smallest size of object that can possibly be detected. For example, when you look at a photograph, the resolution affects how closely you can zoom in on an image before it becomes blurry.

Signal to noise ratio. This measures the electronic “noise” of the detector and compares it with the “background noise” that may interfere with the signals received by the detector. Too much background noise makes it harder to identify a foreign object.

Speed of acquisition. This measures how fast the detector can process the signals it receives. Motion limits what you can see. As line speeds increase, this impacts what detectors are able to pick up.

Material being detected. The type of material being detected and its properties will have a significant impact on the likelihood of detection. As previously mentioned, for example, x-rays are unlikely to detect low-density materials such as cardboard, resulting in a high number of False Negatives.

Presentation or location of material being detected. Materials that are underneath another object, that are presented on an angle, are too similar to the product being inspected, or are partially obstructed may be more difficult for some detectors to find. This also presents a risk of False Negatives.

Complexity of the product under inspection. Product composition and appearance vary. For example, just like the human eye, finding a small object on a uniformly illuminated and uniform color background like a white kitchen floor is much easier than finding the same small object on a complex background like industrial carpet. Coarsely ground meat might be more difficult to detect than uniform back fat layers, for example.

Environment. Conditions such as temperature and humidity will have a significant effect on detection.

Detection Curves

To understand system performance even better, we can use a detection curve. This plots out the likelihood of detection against different variables (e.g., object size) and allows us to objectively compare how these different factors impact the performance of each system.

Figure 3 shows how this looks when plotted as a curve, with object size on the x-axis (horizontal) and the probability of detection (a True Positive from the Confusion Matrix) on the y-axis (vertical). It shows three examples of possible detection curves, depending on the detector being used.

Detection curves
Figure 3. Examples of detection curves for different detectors. Probability of detection of an object increases as the size of the object increases.

A detection curve tells you both the smallest and largest object that a detector will find and the probability that it will be found.

In the example presented by Figure 3, Detector 3 can see essentially 100% of large and very large objects, as can Detector 2. But Detector 3 is also more likely than the other two systems in the example to see microscopic objects. Based on this detection curve it would likely be the best option if the goal were to detect as many foreign objects as possible, of all sizes.

Of course, the performance of a detector is determined by multiple measures, not just size,

Detection capability can be improved for most detection systems, but typically comes at a significant cost: Increasing sensitivity will increase the number of false positives, resulting in increased product rejection. This is why looking at the detection curve together with the false-positive/false-negative rates for any detection system gives us a clear picture of its performance and is invaluable for food processing plants when selecting a system.

Using the confusion matrix and a detection curve, processors can compare different detection systems on an apples-to-apples basis. They can easily see whether a system can identify small, tiny or microscopic objects and, crucially, how often it will identify them.

Every detection method—X -ray, metal detection, vision systems, manual inspection—presents a trade-off between actual (correct) detection, rejection of good product (false positive) and missed detections (false negative). This simple way to compare differences means processors can make the right decision for the specific needs of their plant, based on easily gathered information. For all of us data geeks out there, that sounds like the Holy Grail.

FDA

FDA to Test Yuma-Grown Romaine Lettuce for E. Coli and Salmonella

By Food Safety Tech Staff
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FDA

Today the FDA announced a new plan to collect samples of romaine lettuce as part of its ongoing surveillance after the spring 2018 multistate outbreak of E. coli O157:H7. The samples, which will be tested for Shiga toxin-producing Escherichia coli (STEC) and Salmonella, will be collected from commercial coolers in Yuma County, Arizona during the current harvest season.

FDA plans to collect and test about 500 samples (each of which will consist of 10 subsamples), beginning in February and continuing through the end of the harvest season. In order to reduce the time between sample collection and reporting results, an independent lab close to the collection sites in Arizona will be testing the samples. FDA expects to receive test results within 24 hours.

“Helping to ensure the safety of leafy greens continues to be a priority of the FDA. This assignment adds to other work underway in collaboration with stakeholders in the Yuma agricultural region to implement actions identified in the Leafy Greens Action Plan, including a multi-year study to assess the environmental factors that impact the presence of foodborne pathogens in this region. Consistent with the action plan, the agency will engage with industry on conducting root cause analyses for any positive samples found during this assignment. Root cause analyses are important in that they seek to identify potential sources and routes of contamination, inform what preventive measures are needed, and help prevent outbreaks of foodborne illness,” FDA stated in a release.

COVID-19 precautions will be taken during the sampling plan. Agency investigators will preannounce visits and wear PPE while conducting the work.