Tag Archives: dairy

chicken, beef, dairy, lettuce

Foodborne Illness Report Highlights High-Risk Food Categories

By Food Safety Tech Staff
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chicken, beef, dairy, lettuce

This month, the Interagency Food Safety Analytics Collaboration’s (IFSAC) released it newest annual report , “Foodborne illness source attribution estimates for 2020 for Salmonella, Escherichia coli O157, and Listeria monocytogenes using multi-year outbreak surveillance data, United States.” IFSAC is a collaboration between the CDC, FDA and USDA Food Safety and Inspection Service (FSIS).

The report was developed to help shape the priorities of the FDA, inform the creation of targeted interventions to reduce foodborne illnesses caused by these pathogens, inform stakeholders and improve regulatory agency’s to assess whether prevention measures are working.

The report identified 3,749 outbreaks that occurred from 1998 through 2020 and were confirmed or suspected to be caused by Salmonella, E. coli O157, or Listeria, including 192 outbreaks that were confirmed or suspected to be caused by multiple pathogens or serotypes.

The IFSAC excluded 96 of these outbreaks according to its pathogen-exclusion criteria, leaving 3,653 outbreaks. The agency further excluded 1,524 outbreaks without a confirmed or suspected implicated food, 836 outbreaks for which the food vehicle could not be assigned to one of the 17 food categories, and six that occurred in a U.S. territory.

The resulting dataset for the report included 1,287 outbreaks in which the confirmed or suspected implicated food or foods could be assigned to a single food category. These included 960 caused or suspected to be caused by Salmonella, 272 by E. coli O157 and 55 by Listeria. Outbreaks from 2016 through 2020 provide 71% of model-estimated illnesses used to calculate attribution for Salmonella, 67% for E. coli O157 and 62% for Listeria.

Salmonella illnesses came from a wide variety of foods, with more than 75% of illnesses attributed to seven food categories: Chicken, Fruits, Pork, Seeded Vegetables (such as tomatoes), Other Produce (such as fungi, herbs, nuts, and root vegetables), Beef and Turkey.

More than 80% of E. coli O157 illnesses were linked to Vegetable Row Crops (such as leafy greens) and Beef.

More than 75% of Listeria monocytogenes illnesses were linked to Dairy products, Fruits and Vegetable Row Crops, though the IFSAC noted that “the rarity of Listeria monocytogenes outbreaks makes these estimates less reliable than those for other pathogens.”

Attribution estimates for Campylobacter outbreaks were not included in this year’s report, though they have been included in the past. IFSAC said that this was “due to continued concerns about the limitations of using outbreak data to attribute Campylobacter illnesses to sources … these concerns are largely due to the outsized influence of outbreaks in certain foods that pose a high individual risk for Campylobacter infection but do not represent the risk to the general population.” For example, 91% of reported Campylobacter outbreaks related to dairy products were associated with unpasteurized milk, while 57% majority of chicken-related outbreaks were due to chicken liver products, which are not widely consumed.

Plant based milk

How Advancements in Analytical Testing Are Supporting the Development of Novel Plant-Based Dairy Alternatives

By David Honigs, Ph.D.
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Plant based milk

Globally, milk and dairy products rank among the top eight allergens that affect consumers across the world. In America in particular, 32 million people suffer from some form of allergy, of which a staggering 4.7 million are allergic to milk. Additionally, it is estimated that around 70% of adults worldwide have expressed some form of lactose intolerance. As such, it is important for key stakeholders in the dairy industry to create novel products that meet the wants and needs of consumers.

Low-lactose products have been available since the 1980s. But in recent years, the demand for plant-based alternatives to dairy products has been on the rise. Some of this demand has come from individuals who cannot digest lactose or those that have an allergy to dairy. However, as all consumers continue to scrutinize their food labels and assess the environmental and ethical impact of their dietary choices, plant-based milk has become an appealing alternative to traditional dairy products.

To adapt to this changing landscape, traditional dairy processors have started to create these alternatives alongside their regular product lines. As such, they need access to instruments that are flexible enough to help them overcome the challenges of testing novel plant-based milk, while maintaining effective analysis and testing of conventional product lines.

 David Honigs, Ph.D. will share his expertise during the complimentary webinar, “Supporting the Plant-Based Boom: Applying Intuitive Analytical Methods to Enhance Plant-based Dairy Product Development” | Friday, December 17 at 12 pm ETLow in Lactose, High in Quality

Some consumers—although not allergic to dairy—lack the lactase enzyme that is responsible for breaking down the disaccharide, lactose, into the more easily digestible glucose and galactose.

Low-lactose products first started to emerge in 1985 when the USDA developed technology that allowed milk processors to produce lactose-free milk, ice cream and yogurt. This meant consumers that previously had to avoid dairy products could still reap their nutritional benefits without any adverse side effects.

Similar to conventional dairy products, routine in-process analysis in lactose-free dairy production is often carried out using infrared spectroscopy, due to its rapid reporting. Additionally, the wavelengths that are used to identify dairy components are well documented, allowing for easier determination of fats, proteins and sugars.

Fourier transform infrared (FTIR) technologies are the most popular of the infrared spectroscopy instruments used in dairy analysis. As cream is still very liquid, even at high solid levels, FTIR can still effectively be used for the determination and analysis of its components. For products with a higher percentage of solids—usually above 20%—near-infrared (NIR) spectroscopy can provide much better results. Due to its ability to penetrate pathlengths up to 20 mm, this method is more suitable for the analysis of cheeses and yogurts. For low-lactose products in particular, FTIR technology is integral to production, as it can also be used to monitor the breakdown of lactose.

Finger on the Pulse

For some consumers, dairy products must be avoided altogether. Contrary to intolerances that only affect the digestive system, allergies affect the immune system of the body. This means that allergenic ingredients, such as milk or dairy, are treated as foreign invaders and can result in severe adverse reactions, such as anaphylactic shock, when ingested.

From 2012 to 2017, U.S. sales of plant-based milk steadily rose by 61%. With this increasing demand and the need to provide alternatives for those with allergies, it has never been a more important time to get plant-based milk processing right the first time. Although the quantification of fat, protein and sugar content is still important in these products, they pose different challenges to processors.

In order to mimic traditional dairy products, plant-based milk is often formulated with additional ingredients or as a blend of two plant milks. Sunflower or safflower oil can be added to increase viscosity and cane syrup or salt may be added to enhance flavor. All of these can affect the stability of the milk, so stabilizers or acidity regulators may also be present. Additionally, no plant milk is the same. Coconut milk is very high in fat content but very low in protein and sugar; on the other hand, oat milk is naturally very high in carbohydrates. This not only makes them suitable for different uses, but also means they require different analytical procedures to quantify their components.

Although many FTIR and NIR instruments can be applied to plant-based milk in the same way as dairy milk, the constantly evolving formulation differences pose issues to processors. For example, the way that protein is determined in dairy milk will vary from the way protein is determined in almond milk. Both will follow a method of quantifying the nitrogen content but must be multiplied by a different factor. To help overcome these challenges, many companies have started to develop plant-based milk calibrations that can be used in conjunction with existing infrared instruments. Currently, universal calibrations exist to determine the protein, fat, solids, and sugar content of novel products. With more research and data, it’s likely in the future these will be expanded to generate calibrations that are specific to soy, almond and oat milk.

Even with exciting advancements in analytical testing for plant-based milk, the downtime for analysis is still a lot higher than traditional dairy. This is due to the increased solid content of plant-based milk. Many are often a suspension of solid particles in an aqueous solution, as opposed to dairy milk, which is a suspension of fat globules in aqueous solution. This means processors need to factor in additional centrifuge and cleaning steps to ensure results are as accurate and repeatable as possible.

In addition to the FTIR and NIR instruments used for traditional dairy testing, plant-based milk can also benefit from the implementation of diode array (DA) NIR instruments into existing workflows. With the ability to be placed at- and on-line, DA instruments can provide continual reporting for the constituent elements of plant-based milk as they move through the processing facility. These instruments can also produce results in about six seconds, compared to the 30 seconds of regular IR instruments, so are of great importance for rapid reporting of multiple tests across a day.

Keeping It Simple

Although the consumption of dairy-free products is on the rise, lots of plant-based milk are also made from other allergenic foods, such as soy, almonds and peanuts. Therefore, having low-lactose alternatives on the market is still valuable to provide consumers with a range of suitable options.

To do this, dairy processors and new plant-based milk processors need access to instruments that rapidly and efficiently produce accurate compositional analysis. For dairy processors who have recently started creating low-lactose or dairy-free milk alternatives, it is important that their instrumentation is flexible and used for the analysis of all their product outputs.

Looking towards the future, it’s likely both dairy products and their plant-based counterparts will have a place in consumers’ diets. Although there is some divide on which of these products is better—both for the environment and in terms of health—one thing that will become increasingly more important is the attitude towards the labeling of these products. Clean labels and transparency on where products are coming from, and the relative fat, protein and sugar content of foods, are important to many consumers. Yet another reason why effective testing and analytical solutions need to be available to food processors.

Karen Everstine, Decernis
Food Fraud Quick Bites

Food Authenticity: 2020 in Review

By Karen Everstine, Ph.D.
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Karen Everstine, Decernis

It is fair to say that 2020 was a challenging year with wide-ranging effects, including significant effects on our ongoing efforts to ensure food integrity and prevent fraud in the food system. COVID-19 caused major supply chain disruptions for foods and many other consumer products. It also highlighted challenges in effective tracking and standardization of food fraud-related data.

Let’s take a look at some of the notable food fraud occurrences in 2020:

  • Organic Products. The Spanish Guardia Civil investigated an organized crime group that sold pistachios with pesticide residues that were fraudulently labeled as organic, reportedly yielding €6 million in profit. USDA reported fraudulent organic certificates for products including winter squash, leafy greens, collagen peptides powder, blackberries, and avocados. Counterfeit wines with fraudulent DOG, PGI, and organic labels were discovered in Italy.
  • Herbs and Spices. Quite a few reports came out of India and Pakistan about adulteration and fraud in the local spice market. One of the most egregious involved the use of animal dung along with various other substances in the production of fraudulent chili powder, coriander powder, turmeric powder, and garam masala spice mix. Greece issued a notification for a turmeric recall following the detection of lead, chromium, and mercury in a sample of the product. Belgium recalled chili pepper for containing an “unauthorized coloring agent.” Reports of research conducted at Queen’s University Belfast also indicated that 25% of sage samples purchased from e-commerce or independent channels in the U.K. were adulterated with other leafy material.
  • Dairy Products. India and Pakistan have also reported quite a few incidents of fraud in local markets involving dairy products. These have included reports of counterfeit ghee and fraudulent ghee manufactured with animal fats as well as milk adulterated with a variety of fraudulent substances. The Czech Republic issued a report about Edam cheese that contained vegetable fat instead of milk fat.
  • Honey. Greece issued multiple alerts for honey containing sugar syrups and, in one case, caramel colors. Turkey reported a surveillance test that identified foreign sugars in honeycomb.
  • Meat and Fish. This European report concluded that the vulnerability to fraud in animal production networks was particularly high during to the COVID-19 pandemic due to the “most widely spread effects in terms of production, logistics, and demand.” Thousands of pounds of seafood were destroyed in Cambodia because they contained a gelatin-like substance. Fraudulent USDA marks of inspection were discovered on chicken imported to the United States from China. Soy protein far exceeding levels that could be expected from cross contamination were identified in sausage in the Czech Republic. In Colombia, a supplier of food for school children was accused of selling donkey and horse meat as beef. Decades of fraud involving halal beef was recently reported in in Malaysia.
  • Alcoholic Beverages. To date, our system has captured more than 30 separate incidents of fraud involving wine or other alcoholic beverages in 2020. Many of these involved illegally produced products, some of which contained toxic substances such as methanol. There were also multiple reports of counterfeit wines and whisky. Wines were also adulterated with sugar, flavors, colors and water.

We have currently captured about 70% of the number of incidents for 2020 as compared to 2019, although there are always lags in reporting and data capture, so we expect that number to rise over the coming weeks. These numbers do not appear to bear out predictions about the higher risk of food fraud cited by many groups resulting from the effects of COVID-19. This is likely due in part to reduced surveillance and reporting due to the effects of COVID lockdowns on regulatory and auditing programs. However, as noted in a recent article, we should take seriously food fraud reports that occur against this “backdrop of reduced regulatory oversight during the COVID-19 pandemic.” If public reports are just the tip of the iceburg, 2020 numbers that are close to those reported in 2019 may indeed indicate that the iceburg is actually larger.

Unfortunately, tracking food fraud reports and inferring trends is a difficult task. There is currently no globally standardized system for collection and reporting information on food fraud occurrences, or even standardized definitions for food fraud and the ways in which it happens. Media reports of fraud are challenging to verify and there can be many media reports related to one individual incident, which complicates tracking (especially by automated systems). Reports from official sources are not without their own challenges. Government agencies have varying priorities for their surveillance and testing programs, and these priorities have a direct effect on the data that is reported. Therefore, increases in reports for a particular commodity do not necessarily indicate a trend, they may just reflect an ongoing regulatory priority a particular country. Official sources are also not standardized with respect to how they report food safety or fraud incidents. Two RASFF notifications in 2008 following the discovery of melamine adulteration in milk illustrate this point (see Figure 1). In the first notification for a “milk drink” product, the hazard category was listed as “adulteration/fraud.” However, in the second notification for “chocolate and strawberry flavor body pen sets,” the hazard category was listed as “industrial contaminants,” even though the analytical result was higher.1

RASFF

RASFF, melamine detection
Figure 1. RASFF notifications for the detection of melamine in two products.1

What does all of this mean for ensuring food authenticity into 2021? We need to continue efforts to align terminology, track food fraud risk data, and ensure transparency and evaluation of the data that is reported. Alignment and standardization of food fraud reporting would go a long way to improving our understanding of how much food fraud occurs and where. Renewed efforts by global authorities to strengthen food authenticity protections are important. Finally, consumers and industry must continue to demand and ensure authenticity in our food supply. While most food fraud may not have immediate health consequences for consumers, reduced controls can lead to systemic problems and have devastating effects.

Reference

  1. Everstine, K., Popping, B., and Gendel, S.M. (2021). Food fraud mitigation: strategic approaches and tools. In R.S. Hellberg, K. Everstine, & S. Sklare (Eds.) Food Fraud – A Global Threat With Public Health and Economic Consequences (pp. 23-44). Elsevier. doi: 10.1016/B978-0-12-817242-1.00015-4
Susanne Kuehne, Decernis
Food Fraud Quick Bites

Catching Cosmopolitan Criminals

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

The ninth OPSON operation, a cooperation between Europol and Interpol, included 83 countries around the world. OPSON IX targeted organized crime groups involved in food and beverage fraud. The substandard and fraudulent products potentially pose significant risk for consumers. Animal feed and alcoholic beverages made the top of the list of seized products, followed by grains, coffee and tea, and condiments. The officials also ran special campaigns to uncover fraudulent dairy products, olive oil and horsemeat.

Resource

  1. Europol. (July 22, 2020). “320 Tonnes of Potentially Dangerous Dairy Products Taken off the Market in Operation OPSON IX Targeting Food Fraud”. Press Release.
Megan Nichols
FST Soapbox

COVID-19 Led Many Dairy Farmers to Dump Milk

By Megan Ray Nichols
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Megan Nichols

Much of the news coverage surrounding the COVID-19 pandemic mentions infection numbers and fatalities. Those are undoubtedly important for showing parts of the overall impact. However, it’s easy to overlook the ramifications felt by some professionals. One recent example concerns the instances of dairy farmers dumping milk.

Numerous Factors Contributing to the Problem

The pandemic drastically and dramatically disrupted life. Many of the associated changes affected milk producers, but perhaps not in the ways people expect. As schools closed and restaurants operated on delivery or a takeaway-only basis, the demand for milk typically consumed in the food and educational sector went down.

Consider, too, that the pandemic forced the closure of enterprises that did not necessarily serve large quantities of milk every day but still likely placed ongoing orders with suppliers. For example, a daycare center might give toddlers boxes of dairy beverages each day during snack time. Coffee shops often add milk to their lattes or set out bottles for people who want to put some in their coffee.

When coronavirus cases emerged in the United States, many people panicked and flocked to grocery stores for essentials. Milk is often one of the staples people buy before winter storms hit, and they wanted it to prepare for the pandemic, too. One Target store in New Jersey sold out of its entire stock of milk in only five minutes. Stores responded by imposing per-person limits on the product.

If the demand exists, what caused the milk surplus? Part of it boils down to a lack of space at milk processing plants. A related issue is that processors typically serve particular markets. One might cater to retail buyers while another primarily addresses needs in the food service sector. They lack the infrastructure to pivot and begin accepting milk orders from a new type of customer, particularly if the milk-based product is substantially different, like sour cream versus ice cream.

A First-Time Phenomenon

Farmers discarding milk is not unheard of, but it’s not something many producers do regularly. Andrew Griffith, a professor at the University of Tennessee, said that some farmers had to do it recently for the first time in careers spanning decades. He explained, “It’s not that [dumping] hasn’t occurred from farm to farm.” Adverse weather conditions can delay pickups, and unexpected supply spoilages might lead to too much milk.

“But we’re talking about a level of dumping that is not common at all. There [are] a lot of farmers that are experiencing dumping milk for the first time in their 30- or 40-year careers,” Griffith said in an article published on The Counter.

The highly perishable nature of milk poses another problem contributing to the milk surplus. That aspect hit dairy harder than some other types of agricultural goods. People could put grain into silos, but storage is more complicated for dairy products.

Any exposure to higher-than-recommended temperatures causes spoilage. The subsequent risk to consumers means farmers must throw it away. Cold storage facilities are essential for the dairy industry. Statistics from 2018 indicated an average of 10.67 cents per kilowatt-hour for energy consumption at commercial facilities. However, cold storage facilities operate 24/7, so their energy needs are often higher than those of other commercial buildings.

Cows, dairy, farms
The coronavirus is only one of the challenges likely to impact the dairy industry in the coming months and years. Dairy consumption has been trending down for years. (Pexels image)

The delicate nature of the product is another unfortunate aspect that may lead to dumping milk. If a processor has no room to accept the raw goods, there’s nowhere for them to go. In April The Wall Street Journal reported that in one week, producers threw out as much as 7% of the milk in the United States from that period. The same story highlighted how a specialty cheese factory saw sales of its chèvre and ricotta drop by 95% in one day.

Coping With Dairy Industry Fluctuations

The coronavirus is only one of the challenges likely to impact the dairy industry in the coming months and years. A Statista chart profiles the progressive decline of milk consumption in the United States. The average amount of milk per person in 1975 totaled 247 pounds. It plunged to 149 pounds by 2017.

There’s also the issue of people showing a growing preference for plant-based milk alternatives. One industry analysis tracked sales of traditional and oat milk during mid-March. Purchases for the first category rose by 32%, while oat milk sales soared by 476%. A potential reason for that huge increase in the latter category is that supermarkets sell shelf-stable milk alternatives. Those often stay in date for months when unopened.

People can get them in the refrigerated section, too, but they may have preferred not to as they cut down their shopping trips due to COVID-19. Consumers also noticed the increasing number of milk-like beverages made from hemp, hazelnuts and other options. If a person tries one and doesn’t like it, they may try a different option.

Despite those challenges, some dairy farmers anticipated favorable trends—at least before the coronavirus hit. Producers get paid per 100 pounds of milk. Katie Dotterer-Pyle, owner of Cow Comfort Inn Dairy, said 2013 was a particularly good year for the rates. Back then, farmers received about $30 for every 100 pounds, although the price has stayed at approximately $17 per 100 over the past two years.

When Might the Milk Surplus Ease?

This coverage emphasizes the lack of a quick fix for the dairy industry strain. As restaurants reopen, that change should help address the problem, but it won’t solve it entirely. Some enterprises refocused their efforts to better meet current demands. One Dallas-based plant that handles dairy products more than halved its output of cardboard milk cartons and increased production of whole and 2% milk for the retail sector. It is now back to normal manufacturing runs.

As mentioned earlier, though, many processors can’t make such changes. Dumping milk becomes a heart-wrenching practice for hard-working producers. Many tried to compensate by selling their least-profitable cows for slaughter or making feeding changes to reduce the animals’ production. Some private entities committed to purchasing milk from farms and getting it to food banks. Other analysts say the government should step in to help.

People in the farming community support each other with tips and reassurance, but most know they could be in for a long struggle. As supply chains recovered from the initial shock of COVID-19, most people stopped panic buying, and stores no longer set product limits. Things are moving in the right direction, but the impacts remain present.

A Complicated Issue

Many state leaders have let businesses reopen, and others are following. Any step toward a new kind of normal is a positive one that should gradually help the dairy sector. However, much of what the future holds remains unknown, mainly since this is a new type of coronavirus, and scientists still have plenty to learn about mitigating it.

Susanne Kuehne, Decernis
Food Fraud Quick Bites

Organic Foods Are Growing And So Is Fraud

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

USDA Certified Organic foods keep enjoying a robust growth, with fruit and vegetables leading, followed by dairy and beverages. Fraudulent organic certification is a growing problem, especially because food supply chains are becoming more complex, with a large amount of organic food now being imported. Violations by fraudulent organic certification are punishable by hefty fines and can be reported to the National Organic Program Online Complaint Portal.

Resource

  1. United States Department of Agriculture (March 9, 2020) Scientific Reports 9: “Fraudulent Organic Certificates”.
Dairy

Q3 Hazard Beat: Milk & Dairy Products

By Food Safety Tech Staff
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Dairy

The following infographic is a snapshot of the hazard trends in milk and dairy from Q3 2019. The information has been pulled from the HorizonScan quarterly report, which summarizes recent global adulteration trends using data gathered from more than 120 reliable sources worldwide. For the past several weeks, Food Safety Tech has provided readers with hazard trends from various food categories included in this report. Next week will conclude this series.

Mailk dairy hazards, HorizonScan
2019 Data from HorizonScan by FeraScience, Ltd.

View last week’s hazards in fruits and vegetables.

Cargill, facial recognition technology

Facial Recognition for Cows? The Future Is Here

By Food Safety Tech Staff
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Cargill, facial recognition technology

Facial recognition technology could be the next step in improving efficiency on dairy farms. Cargill is investing in Dublin-based Cainthus, a company that uses machine vision technology and predictive imaging to monitor livestock. In just seconds, Cainthus’ proprietary software’s imaging technology identifies cows by their features and captures their identity by recording specific patterns and movements. In addition to monitoring behavior patterns, the software can track data such as food and water intake, and heat detection.

“Our shared vision is to disrupt and transform how we bring insights and analytics to dairy producers worldwide. Our customers’ ability to make proactive and predictive decisions to improve their farm’s efficiency, enhance animal health and wellbeing, reduce animal loss, and ultimately increase farm profitability are significantly enhanced with this technology.” – SriRaj Kantamneni, managing director for Cargill’s digital insights business

An artificial intelligence driven mathematical algorithm generates analytics that can send farmers an alert to help them make on-site decisions that impact milk production, reproduction management and overall animal health, according to a Cargill press release.

The companies are concentrating on the dairy industry first and plan to expand to swine, poultry and aqua over the coming months.

Weber Scientific

Rapid PCR Test for Finished Dairy Products Hits Market

By Food Safety Tech Staff
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Weber Scientific

Weber ScientificA new PCR yeast and mold test that provides results in just four hours is available for finished dairy products. Developed by Germany-based Biotecon Diagnostics, the foolproof yeast and mold quantification test has demonstrated 100% specificity with 290 strains, representing 260 species with all phylogenetic groups included, according to a release from Weber Scientific. It also demonstrated 100% exclusivity with 60 strains of non-target microorganisms typically found in similar ecological niches (Sensitivity is 101 – 102 cells / g depending on sample type).

“This test is based on well-established real-time PCR technology,” said Phil Coombs, product specialist at Weber Scientific. “There is a high degree of correlation between conventional methods and PCR. Results are displayed in CFU per gram and only viable organisms are detected…The real cost benefits will be achieved by how much more quickly can product be shipped and how many recalls avoided.”

Sangita Viswanathan, Former Editor-in-Chief, FoodSafetyTech

Implementing an Effective Listeria Control Plan for Dairy Products

By Sangita Viswanathan
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Sangita Viswanathan, Former Editor-in-Chief, FoodSafetyTech

In the last three years, there have been four major foodborne illness outbreaks caused by Listeria monocytogenes in dairy products (Oasis fresh curd cheese; Roos raw hard cheese; Crave Brothers pasteurized farmstead cheese; and Frescolina Marte pasteurized ricotta cheese). Before 2012, there have been multiple outbreaks due to raw and pasteurized Mexican-style soft cheeses and in pasteurized milk in 2007.

Dr. Douglass Marshall, Chief Scientific Officer – Eurofins Microbiology LaboratoriesDr. Douglass Marshall, Chief Scientific Officer – Eurofins Microbiology Laboratories , recently spoke about Implementing an effective Listeria control plan for Dairy Products in a recent presentation. He described the pathogen as “a gram-positive bacteria, which is facultatively anaerobic, psychotrophic (can even multiply at refrigeration temperatures – though at slower rates), sensitive to heat processing, even found in healthy cows, raw milk and dairy processing environments, and can survive most cheese ripening processes.”

Though, listeriosis, the infection caused when a person is infected with LM, is relatively rare – only affecting about 1600 individuals a year – it has a high mortality rate, highest among foodborne illnesses, especially among high-risk individuals.

Dr. Marshall listed some of the contributing factors to a LM outbreak:

  • Inadequate thermal processing
  • Refrigeration temperature being too high
  • Inadequate product flow through processing plant
  • Inadequate personal hygiene
  • Product shelf-life too long
  • Inadequate cleaning and sanitation
  • Inadequate environmental monitoring and control
  • Inadequate end product testing

Thermal processing is a time-temperature process, and it can be inadequate if either the temperature is too low, or the process time is too short.

It is common knowledge that whether it’s during transportation, or at retail or at homes, often temperature of food storage is not adequately maintained. Dr. Marshall said that as high as 55 percent of household units and 32 of retail store units had refrigeration temperatures of greater than 9 °C. “And once you get past that temperature threshold of 10 °C, the bacteria reaches maximum population level within six days (average shelf life).”

Inadequate cleaning & sanitation is another major cause for LM contamination and this is often the battle between production & sanitation. Floor drains are a common culprit, responsible for 63 percent incidence of LM. Dr. Marshall also referred to other sources of inoculation that you are not getting effective control of such as filler heads and high pressure water sprays or air sprays, which can aerosolize bacteria and spread the contamination to other surfaces.

Inadequate product flow is usually due to the failure to segregate pasteurized product form raw product or the failure to segregate employees working in raw vs. pasteurized locations. Address this by mapping out product and employee flow (along with equipment) and look for areas where cross contamination can occur, advises Dr. Marshall, who cautions facilities to monitor and control the following direct food contact surfaces that can be cross-contaminated:

  • Fillers
  • Packaging stems
  • Conveyors
  • Chilling solutions
  • Slicers, dicers, shredders, blenders, hoops, molds
  • Collators, assemblers
  • Product movement items, such as racks, bins, tubs and buckets
  • Spiral coolers, blast freezers
  • Hand tools, gloves, aprons

Inadequate personal hygiene is another contributing factor and this can include clothing such as outerwear and gloves. Maintenance personnel should be thorough in their hand-washing and it’s recommended they use alcohol based wipes after hand-washing.

Address the issue of shelf-life being too long by determining the shelf life based on food safety, and not food quality. Also, run LM challenge test in each product, Dr. Marshall advises.

Eurofins-LM-in-Dairy-webinar-March2015

FDA, in their Preventive Controls rule proposed under the Food Safety Modernization Act, has a section on Environmental Monitoring, based on the rationale that that poor control of the environment can lead to LM cross contamination of finished product, explains Dr. Marshall, adding that inadequate environmental monitoring and control is a key component for LM contamination.

“Invest your testing dollars to find hot spots in your facility and ensure the control mechanisms are working every day,” he says, asking companies to “detect and control hot spots, measure effectiveness of general cleaning and sanitation programs, and test for Listeria species.”

Dr. Marshall asks, “If I were LM and wanted to hide, where would that be? Would it be on an easy to clean surface such as the floor, or would it be in a nook or cranny where it’s hard to reach and clean?” He lists the following as areas that commonly harbor the pathogen and advises extra caution and creativity to clean these spots:

  • Equipment framework – nuts, bolts, open tubing, spot welds
  • Floors and drains – standing water
  • Walls
  • Ceilings, overhead equipment, catwalks, pipes
  • Condensate
  • Exposed, wet insulation around pipes and walls
  • Fork lifts, trolleys
  • Cleaning tools – sponges, brushes, scrubbers
  • Maintenance tools
  • Conveyors, belts and rollers (need to be broken down and cleaned regularly)
  • Control panels and switches
  • Rubber seals (especially if they have cracks)
  • Trash cans
  • Air fillers
  • Motor/ pump housings
  • Cracked hoses
  • Ice makers

End product testing is an effective way for testing for LM, but Dr. Marshall points out that there are often arguments against this. “Companies often argue that their HACCP plan is working, their kill step is effective and that they have a history of doing end product testing, and they haven’t had any positive results so far. But this is not a convincing enough argument.” End product testing can address the failure to monitor and control high risk ingredients, and is very useful to detect gross contamination events. It should be used to assess risk of rework, and also test for LM, not just Listeria, Dr. Marshall advises.

Hear more about building an effective control plan for Listeria in your dairy processing environment, by listening to this archived webinar recording, presented by Eurofins.