Food Fraud: Is there really tuna in canned tuna?

Operation OPSON VII (2017/2018) focused on cases of fraud involving tuna across Europe. A central problem was the illegal treatment of tuna with unauthorized substances in order to simulate a fresher red color and thus sell inferior or older goods as high-quality. Such practices not only deceive consumers, but can also pose health risks. During the operation, 15 cases of illegally dyed tuna were identified in Germany. This raised doubts as to whether there really was tuna in the canned tuna or whether cheaper, non-animal ingredients had been used.

The international OPSON operations aim to uncover and combat food fraud.

What is food fraud?

Food fraud is a growing challenge in the area of food safety. It involves the deliberate deception of consumers through the manipulation, adulteration or false declaration of products in order to gain financial benefits. Such cases of fraud are particularly common with fish and meat, as these products are in high demand and have a high market value. Examples range from the labeling of low-quality fish as a high-quality species to the admixture of undeclared meat species or the falsification of certificates of origin. Such practices not only damage consumer confidence, but can also pose health risks, especially when contaminated with unauthorized substances or allergens. Therefore, close control and monitoring of supply chains and the use of modern analytics is crucial to effectively combat food fraud in fish and meat.

Which tuna is in the can?

Tinned or canned tuna usually comes from species that are caught in large quantities and are considered commercially viable. The most common types of canned tuna are:

Skipjack tuna (Katsuwonus pelamis):

• most commonly used worldwide because it is comparatively cheap
• closest relative of the eight tuna species (Thunnus sp.)
• flesh has a lighter, pink to grey color

Yellowfin tuna (Thunnus albacares):

• known for its slightly firmer and yellowish flesh tone
• often considered to be of higher quality and marketed as “yellowfin tuna” or “tuna fillet”

Albacore tuna (Thunnus alalunga):

• flesh is lighter in color, almost white
• is referred to as “white tuna” and is considered a premium product

In some cases, lower quality tuna or mixed species are used. It is therefore advisable to look for sustainability certificates such as the MSC seal (Marine Stewardship Council) to support environmentally conscious products.

We use real-time PCR to detect food fraud in canned tuna

The Tentamus Group's lifeprint GmbH laboratory has developed a sensitive real-time PCR that can be used to detect real tuna. The test is based on mitochondrial sequences, which are much more abundant in the cell than the nuclear genome, and can therefore also be used very well for processed materials such as canned tuna.

Real-time PCR is a modern and highly precise method for the amplification and quantification of DNA in real time. It provides fast and reliable results for the detection of pathogens, allergens and genetically modified organisms (GMOs). In contrast to conventional PCR, real-time PCR enables simultaneous monitoring of the amplification process during each cycle.

In the food safety industry, real-time PCR is primarily used to identify pathogens such as salmonella, listeria or E. coli. The method is also used to detect GMOs in products and to ensure compliance with legal labeling regulations.

The method is characterized by its high sensitivity, as it can detect even the smallest amounts of DNA, as well as its specificity, which makes it possible to identify precisely defined target sequences. It therefore makes a significant contribution to ensuring food safety and not only helps to meet legal requirements, but also strengthens consumer confidence in the quality and safety of food.

The laboratories of the Tentamus Group support you

Are you a producer or distributor of canned tuna and want to check whether your canned products really contain tuna? Or would you like to prove to your customers that you really do use tuna?

Then the Tentamus Group laboratories can support you with analysis and advice!

The laboratory analysis services in molecular biology from lifeprint GmbH include:

• Real Time PCR
• ELISA
• Enzymatics
• sequencing
• Residue analysis and microbiology

We ensure the quality of our analysis through sophisticated control systems, continuous optimization and a special room concept that guarantees contamination-free sample handling. External audits, successful round robin tests and participation in EU validation studies confirm our outstanding work. Since 2002, lifeprint GmbH has been accredited according to DIN EN ISO/IEC 17025, and measurement results are always critically reviewed.

Contact our expert today:

Dr. Katrin Neumann
Site management lifeprint GmbH
T +49 7303 95105 18
Katrin.neumann@lifeprint.de