Investigation of the Impact of Can-filling Medium on the DNA Quality of Canned Tuna Sold in Supermarkets

Abstract

Canned tuna is one of the most commonly consumed food products globally. Due to its high profitability and the increasing demand for it, fraudulent canned tuna products have become a serious problem. The traceability of fish species in packaged material and, in the case of highly processed forms, in canned products, has become impossible; therefore, canned tuna is on the list of the top ten food items affected by fraud. These fraudulent actions cause not only unfair trade in the commercial market and fishing industry, but also cause health damage (such as allergies and poisoning) to the public. Complex food matrices also affect the extracted DNA quality when the main food products are served with another medium. Brine solutions, different kind of oil, and several types of sauce are used as filling medium in the canned tuna production process. These filling medium can cause contamination depending on whether they include oil, salt or other ingredients during DNA extraction from main products. DNA-based protocols have become popular due to their higher reliability rate compared to other protocols. This research investigates the potential impact of can-filling medium on DNA quality, which is a key factor for food traceability research. With this aim, canned tuna from various brands in different can-filling medium such as olive oil, sunflower oil and different kinds of sauces, were obtained from a Turkish supermarket. The quality properties, such as yield and purity, affected the traceability analyses. This study was designed to investigate the potential effect of the filling medium on DNA quality. The results revealed that different kinds of sauce utilization as a can-filling medium cause a reduction in the DNA quality of canned tuna compared to other canned tuna samples that contain olive oil and sunflower oil. The purity of extracted DNA in canned tuna where olive oil was used was found to be relatively higher than other tuna groups with different can-filling medium. Melting curve analyses revealed that sunflower oil causes relatively lower degradation than olive oil and different types of sauce used as filling medium. These results could be beneficial for further seafood traceability research, especially in complex matrices.