Species substitution in goat yoghurt supply chain using melting-curve analysis

Mislabelling of dairy products has been widely reported worldwide but there are relatively few data available to help assess species substitution in goat yogurt. The purpose of this study was to investigate the presence of bovine and sheep milk in yogurt labeled as being made exclusively from goat milk, using qualitative real-time PCR. The results confirm that fermented products are targets for food species substitution, highlighting the undeclared presence of cow and/or sheep milk in 39.6% of samples analysed. Moreover, the study shows that the qualitative real-time PCR used here is a rapid, sensitive (LODabs of 0.015 ng/mu L), specific (no primer-dimers or non-specific products in the reactions), straightforward and low-cost molecular tool for discriminating adulterants in the dairy supply chain. Therefore, melt-curve analysis is a promising tool for facilitating routine safety, quality and authenticity checks in the dairy industry, and for implementing mitigation strategies against fraudulent activities. Application of DNA-based approaches is crucial for designing an innovative food safety management system and for helping to implement both a Food Fraud Vulnerability Assessment and a Food Fraud Prevention Strategy as common practices in the dairy sector

Species authentication of canned mackerel: Challenges in molecular identification and potential drivers of mislabelling

The market for canned mackerel is growing, due to their competitive price and to the excellent properties of the meat. However, the weak rules of current legislation, coupled with the loss of discrimination power due to being obliged to use short barcode regions, open up new challenges for traceability in processed products. In this study, for the first time, we applied a two-step mini-barcoding approach to identify canned mackerel sold in Italian markets and make assumptions on the potential drivers of mislabelling. Preliminary identification was performed using mini-barcode universal primers targeting a COI-fragment; then, in order to discriminate within the complex Scomber colias/S. japonicus/S. australasicus, we applied a second step, using new specific primers designed in the mitochondrial control region (D-loop). Comparison between labels and molecular identifications highlighted that the chance of mislabelling could be either 45% or 0%, depending on the interpretation of the generic terms used on the labels. Therefore, the study revealed that the ambiguous use, in the ingredient list, of ‘umbrella’ terms for naming fish species, such as ‘sgombro’ could be related to geographic origin of products and creates opportunities for fraudulent activities, but also misleads consumers. In light of this pattern, an urgent update of European legislation is needed to face current and future challenges for full chain traceability

Microbiome-based study in wild-caught Scomber scombrus fish products at the end of the supply chain

Fresh fish remain the dominant seafood forms and preservation technologies have enabled them to access ever more distant markets. In this study, we used metabarcoding of the 16S rRNA gene to generate gill microbiomes from Scomber scombrus bought at fishmonger’s stores as fresh products but whose labels showed they had been harvested in the Atlantic or Mediterranean FAO fishing areas. Microbial data were analysed with the aim of evaluating their ability to maintain signals from their different geographical origins and the presence of taxa which can potentially act as spoilers, foodborne pathogens, or histamine producers. Results revealed that microbiota, at the end of the wild fish supply chain, had differences related to the two FAO fishing areas (Atlantic vs Mediterranean). Despite the presence of microbial genera potentially associated with spoilage, histamine- production or foodborne pathogens, their patterns confirmed that low-temperature storage is a traditional but effective method of preservation. However, the ongoing spoilage processes were more evident in fresh non-local specimens, dominated by psychrophilic Gram-negative bacteria, whereas fresh local specimens contained Planctomycetes taxa. Therefore, despite the current limitations mainly related to time and cost of the method, our study highlighted that microbiome-based applications are an emergent tool for food system transformation