DNA metabarcoding for identification of species used in fish burgers

Abstract

The absence of morphological identification characters, together with the complexity of the fish supply chain make processed seafood vulnerable to cases of species substitution. Therefore, the authentication and the traceability of such products play a strategic role in ensuring quality and safety. The aim of the present study was to detect species used in the production of multi-species fish burgers and to evaluate mislabelling rates, using a DNA metabarcoding approach by sequencing a fragment of the 16S rRNA mitochondrial gene. The study highlighted the presence of 16 marine and 2 mammalian taxa with an overall mislabelling rate of 80%, including cases of species substitution, the undeclared presence of molluscs and of taxa whose use is not permitted by current Italian legislation. The presence of swine DNA as well as the inclusion of undeclared taxa potentially causing allergies raise concerns regarding consumer safety and protection regarding ethical or religious issues. Overall, the study shows that the application of DNA metabarcoding is a promising approach for successfully enforcing traceability systems targeting multi-species processed food and for supporting control activities, as a guarantee of an innovative food safety management system.

Is the metabarcoding ripe enough to be applied to the authentication of foodstuff of animal origin? A systematic review

“…Additionally, cases of allergy to meat from mammals and birds, beef, pork, lamb, and poultry, have become more common starting around 20 years ago (Mottola et al., 2023). In the analyzed SPs, health risks possibly related to the presence of allergenic ingredients were highlighted in seafood products (Giusti, Armani, et al., 2017; Mottola et al., 2022, 2023; Piredda et al., 2022).…”

“…. Among the included SPs, only three (13.0%) used this approach, all published in the last 2 analyzed years (Klapper et al., 2023; Mottola et al., 2022; Mottola et al., 2023), proving that the scientific community is becoming aware of the importance of the pipeline selection.…”

“…Four of them set the threshold to filter data to 1% (Kappel et al., 2017; Klapper et al., 2023) or 2% (Chaora et al., 2022; Xing et al., 2021). The other two SPs (Mottola et al., 2022; Piredda et al., 2022) removed the sequences with a total abundance of ≤50 reads. Although the selection of a percentage value to filter the data is to be preferred over the number of reads as less influenced by the sequencing output (overall reads number), this approach is also used by other authors applying metabarcoding to experimental food mixtures (Liu et al., 2021).…”

“…. Among the included SPs, only three (13.0%) used this approach, all published in the last 2 analyzed years (Klapper et al, 2023;Mottola et al, 2022;Mottola et al, 2023), proving that the scientific community is becoming aware of the importance of the pipeline selection. The remaining six SPs (26.1%) used Pip-2, including services provided by external companies that used inhouse developed pipelines, or trademark pipelines associated with the sequencing platform (viz., Ion Torrent and MinION-Oxford Nanopore).…”

Convergent technologies to tackle challenges of modern food authentication

“…Therefore, techniques based on High Throughput Sequencing Technologies (HTS) like DNA metabarcoding can meet this requirement [ 7 , 8 ]. These approaches have for example been successfully used to identify the composition of honey [ 9 ], spices and herbal teas [ 10 ], complex matrices such as burgers [ 11 ], but also for insect-based novel food quality control [ 12 ].…”