Meat Authenticity and Tackling Meat Fraud
In 2013, the discovery of horsemeat and other undeclared meats within products claiming to be beef set alarm bells ringing across the continent.
Complete the form below to unlock access to ALL audio articles.
For many, the horsemeat scandal that rocked the European food industry in 2013 would have been the first time they became truly aware of the vulnerabilities within the meat supply chain.
The discovery of horsemeat and other undeclared meats within products claiming to be beef set alarm bells ringing across the continent, resulting in public outcry, product recalls and serious investigations on behalf of European food authorities.1
As a result of these investigations, attitudes within the industry have changed considerably; analytical testing and surveillance systems became fully integrated as a part of standard practice and the industry as a whole is now more prepared to tackle incidents of suspected fraud.1
There are many analytical tools at food scientists’ disposal that are used to detect food fraud in edible products.2 DNA-based screening methods are particularly important for assessing meat origins and authenticity, while other untargeted methods can help detect the presence of unknown adulterants.
Food fraud in the meat industry
The COVID-19 pandemic is perhaps the most recent, stark reminder of the vulnerability of the current food supply chain.3 Alongside concerns over food supply, the continued disruption highlighted the opportunities that bad actors have to scale up fraudulent operations within the food industry.
“Food fraud is the act of mislabeling or misrepresenting a food item such that it deceives the consumer into thinking that a product has a certain origin or composition, and is usually motivated by economic profit,” said Dr. Bryan Quoc Le, a food scientist, consultant and faculty research fellow at Pacific Lutheran University.
While the shock factor of consuming a completely different species propelled the horsemeat scandal into the headlines, other attempts at food fraud may be more subtle. A fraudulent producer might claim that their animals were organic or grass-fed, or reared free-range when this is not true, Le explained. Some producers might try to pass off cheaper cuts of meat as being more expensive than they really are, motivated by the high cost of meat. Others might attempt to disguise or not disclose their use of certain antibiotics or illicit growth hormones.
“Meat is particularly susceptible to food fraud. Meat products could be adulterated with food colorants or have fraudulent claims of origin, breed, production method, and meat age,” Le said. “Other potential issues include labeling thawed or previously frozen meat as fresh and the undeclared use of antibiotics or hormones.”
To ensure that the products reaching the consumer market are authentic, the food industry uses analytical testing at various points throughout the supply chain. This testing can be done proactively at set quality control points, or it can be used reactively in response to a consumer complaint or tip-off from a whistleblower concerning a certain product or manufacturer.
“Quality control checkpoints at reception are important to determine if adulteration or fraud has occurred. Points at which the meat has gone through distribution or storage are also key points in which analytical testing can serve to evaluate when food fraud has been committed,” Le said.
Common approaches to meat authenticity analysis
DNA- or protein-based tests are the most common type of analytical technique used to confirm the authenticity of meat products.
One rapid and easy-to-use protein-based screening solution is the enzyme-linked immunosorbent assay (ELISA).4 This immunological technique uses enzymes to detect the presence of certain antibodies or antigens in a sample and can be used both qualitatively or quantitatively.
Qualitative use is most common, but quantitative methods have been developed too, to determine the content of certain meats in mixed meat products, for example.5 ELISA screening is also used to confirm if certain foodstuffs are halal or kosher, by quickly screening products to ensure that there has been no contamination or adulteration by pork meats.6
For analyses where more specificity and sensitivity are required, testers may instead opt for a DNA-based method.7
DNA-based methods, such as polymerase chain reaction (PCR), are an appropriate method for the analysis of raw meat or other products that have not undergone extensive processing, as it can be challenging to extract intact DNA from overly processed meats, stocks or gelatins.
These tests target certain DNA sequences by using specific primers and probes. These DNA sequences are amplified, which allows them to be detected with extremely high specificity. This makes DNA testing a very effective tool that can deliver excellent confidence in terms of species identification.
Developing relevant primers does require a significant investment of expertise. However, once these primers are engineered, screening can be done very cheaply and very quickly. This contributes to the popularity of DNA-based tests for the routine screening of meat products for fraud.
Alternatively, it is also possible to use universal primers to amplify sections of DNA that are likely to contain species-specific variations, in a process known as DNA barcoding. This type of approach is often used for species identification and as an identification tool for halal foods.8
“Certain cheaper cuts of meat could be masqueraded as more expensive meats, due to the high cost of meat.” – Dr. Bryan Quoc Le.
"DNA-based testing is often used to authenticate species or to identify the addition of undeclared plant or animal ingredients,” said Dr. Rosalee Hellberg, associate director of the Food Science Program at Chapman University. “Additional approaches, such as capillary electrophoresis (CE), enzyme-linked immunosorbent assay (ELISA), isoelectric focusing (IEF) and high-performance liquid chromatography (HPLC) can also be used to identify biomarkers associated with different adulterants.”
“Microscopy can also be used to determine partial replacement with other animal tissues, for example, use of different types of animal tissue in pet foods,” Hellberg added.
Novel analytical techniques provide new insight
DNA- and protein-based meat fraud screening techniques are well-suited for cases where a specific type of fraud must be ruled out, i.e., where a specific adulterant is already suspected of having come into contact with a product.
For other cases, where an investigator may wish to cast a wider net for possible adulterants, there is a need for alternative “untargeted” screening methods.
“Untargeted approaches that result in a chemical or biological fingerprint are increasingly being developed using techniques such as isotope ratio mass spectrometry (IRMS), spectroscopy and chromatography,” said Hellberg. “Oftentimes, a combination of targeted and untargeted testing is warranted to allow for the detection of both known and unknown adulterants.”
Untargeted screening based on spectroscopic methods has evolved over the past several years, becoming an invaluable tool that can be used in combination with targeted methods to overcome some of their limitations.9
One recent study demonstrated the use of Fourier transform infrared (FTIR) spectroscopy in non-destructively characterizing real-world samples of adulterated bovine meat. Using attenuated total reflectance FTIR (ATR-FTIR), the method was able to distinguish between control samples and real adulterated products that had been injected with non-meat ingredients (including salt, phosphates, carrageenan and maltodextrin), which had been seized in a police operation.10
Mass spectrometry approaches, including matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF), are also commonly used for untargeted screenings. MALDI-TOF is a flexible technique that can be applied to many food fraud detection scenarios, including the analysis of gelatins and the distinguishing of meat that has been frozen-thawed from kept fresh. 11, 12
“There is also a demand for analytical tools that can be used in the field, for example, to screen incoming foods at customs or test raw ingredients received at a processing facility,” Hellberg said. “Some examples of tools that could be used in the field include handheld spectroscopic devices and portable real-time PCR instruments.”
One such handheld device that is gaining ground in the sector is the handheld near-infrared (NIR) spectrometer. As the name suggests, this is a vibrational spectroscopy technique that utilizes the near-infrared part of the electromagnetic spectrum. Such analysis is rapid, non-destructive and extremely useful for the chemical fingerprinting and screening of a wide variety of sample types. It has already been used within the food sector for investigating freeze-thawed and fresh mutton, the authentication of lard and detecting the adulteration of beef products with spoiled beef. 13, 14, 15
Such targeted and untargeted analytical chemistry techniques are crucial for securing the global meat supply chain, preventing adulteration and food fraud and ensuring that specialist products such as halal and kosher foods are correctly labeled. But the buck does not stop where testing ends, Hellberg emphasized.
“It is important to point out that analytical testing by itself is not sufficient to combat food fraud,” said Hellberg. “Instead, a comprehensive approach is required that combines analytical testing with additional control measures, such as robust auditing programs, supplier raw material documentation and anticounterfeiting technologies.”
About the interviewees:
Rosalee Hellberg, PhD is an associate professor and the associate director of the food science program at Chapman University. Dr. Hellberg received an MS and PhD in food science and technology at Oregon State University and was a commissioner’s fellow at the U.S. Food and Drug Administration (FDA). At Chapman University, Dr. Hellberg teaches classes on food fraud, food microbiology, and the food industry. She also runs the food protection laboratory, which develops and applies rapid methods for the detection of food fraud and food contaminants. Dr. Hellberg has published over 50 peer-reviewed articles and book chapters. She is also the lead editor for the recently published book Food Fraud: A Global Threat with Public Health and Economic Consequences.
Bryan Quoc Le, PhD earned his PhD in Food Science from the University of Wisconsin, Madison, where he studied the biological effects of plant-based flavors on mammalian tissues. He is currently a faculty research fellow in the department of chemistry at Pacific Lutheran University. He also regularly consults for a number of startups and companies in the food industry.
