Fish and Seafood fraud: Concerns beyond mislabelling

Although species mislabelling is the most common type of fraud that affects fish and seafood products, there are other aspects of fish fraud that should be considered. 

Adulteration with formaldehyde is a concern

The Decernis Food Fraud database lists 15 incidents of fish and seafood adulteration with formaldehyde. These incidents occurred in Hong Kong (2010), India (2013, 2014, 2018 and 2022), Indonesia (2006, 2013 and 2020), China (2008 and 2017), Bangladesh (2014) and Uganda (2018).

Fraudsters may use formaldehyde as a preservative to make fish appear fresher for longer. It is tasteless and odourless, making it difficult for consumers to detect. It is also readily available and inexpensive.

Formaldehyde is not permitted for use in foodstuffs and poses health concerns.

Formaldehyde can easily be detected using gas chromatography coupled with mass spectrometry (GC-MS). Contact FACTS for more information.

Frozen-thawed fish sold as fresh fish is another issue

When fish is frozen and then thawed, there is a change in the amount and distribution of moisture within the muscle tissue, which alters the muscle texture and water-holding capacity of the product. Such quality changes may be seen as undesirable and may drive consumers and producers to purchase fresh fish rather than frozen-thawed fish.

Because fresh fish spoils quickly, the supply chain needs to be considerably shorter compared to that for frozen fish. This makes fresh fish more expensive than frozen fish, which creates opportunity for fraud. Frozen-thawed fish may be sold as fresh fish to generate higher profits.

Distinguishing between fresh and frozen-thawed fish based on sensory properties is not always possible. Analytical methods are needed to differentiate between these products.

Various techniques have shown to be successful in distinguishing between fresh and frozen-thawed fish for specific species, including histology, proteomics, and various spectroscopic techniques.

Fish may contain undeclared contaminants

A 2019 study by Ojemaye & Petrik found fish caught off the coast of Cape Town, South Africa to contain pharmaceutical and industrial chemical compounds, including anti-inflammatory drugs, antibiotics, disinfectants, flame retardants and pesticides. These compounds enter the ocean via agricultural runoff, polluted storm water and the disposal of untreated sewage into the marine environment and bioaccumulate in fish tissue.

The study showed the concentration of most of these compounds to be highest in the fillets of the fish samples collected, which is concerning as this is the part that is typically consumed.

Although the occurrence of these compounds is not a deliberate, economically motivated act of fraud, it contravenes the Consumer Protection Act, 68 of 2008, which serves to protect consumers from hazards to their wellbeing and safety and to sets out consumers’ rights to safe, good quality goods.

If you are concerned about a particular contaminant in a fish or seafood product, or would like to know more on this topic, please contact us for more information.

Testing plays an integral role in the food fraud journey. It is a valuable tool that helps confirm product authenticity, which in turn, protects brand integrity.

Because there are many factors to consider when testing for fraud, it is best to discuss your request with the testing laboratory to ensure that the method used is appropriate and reliable. For more information, please contact FACTS.

Other articles you may be interested in:
FISH AND SEAFOOD FRAUD: Species mislabelling
CASE STUDY: The murky waters of the tuna controversy