In relation to consumer demand, crustaceans and cephalopods are sold as both fresh and defrosted. It is well known that total volatile basic nitrogen (TVB-N) and volatile amine values, especially, biogenic amines and biogenic amine index, are expression of freshness of fish products, but there is a lack of knowledge of their acceptability limits, for crustaceans and cephalopods. In order to assess these limits, real-time shelf life tests were carried out, relating the results of TVB-N, biogenic amines and BAI to the sensory evaluation of crustaceans and cuttlefishes, both fresh and defrosted. TVB-N and biogenic amines have been analysed in many shrimp species and cuttlefishes purchased in Perugia (Central Italy), and BAI was calculated as the ratio between different biogenic amines. The results show levels of TVB-N and spermine different between shrimp and cuttlefish (TVB-N: 37 vs. 14 mg/100 g; spermine: 4 vs. 14 mg/kg, respectively) while the other biogenic amines and BAI are close to zero in both. Among biogenic amines, cadaverine and even more putrescine significantly affect BAI values and seem to be the most effective in assessing limits of acceptability during storage.

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Summary Bdellovibrio bacteriovorus is a predator micro‐organism towards other Gram‐negative bacteria. We tested B. bacteriovorus to control Escherichia coli growth on chicken slices and canned beef. Moreover, we analysed B. bacteriovorus's lytic ability on eight toxigenic or multidrug‐resistant E. coli strains. In chicken slices, the predator induced the highest prey reduction (4.3 log) respect to control at 6 h. In canned beef, the predator induced the highest prey reduction (2.1 log) respect to control at 6 h. Moreover, B. bacteriovorus showed lytic ability towards all tested E. coli strains. B. bacteriovorus could control E. coli and other pathogenic and spoilage bacteria in those meat‐based foods that have a shelf life <10 days. It could integrate modified atmosphere packaging (MAP) to prolong the shelf life and improve the safety of pre‐packed fresh meat, meat preparations and meat products. In future applications on meat‐based foods, B. bacteriovorus could also minimise the use of additives.

Food allergy is a worldwide health problem that concerns infants to adults. The main health risk for sensitised individuals is due to the presence of traces of allergens as the result of an accidental contamination during food processing. The labelling of allergens such as sesame, pistachio, and macadamia nut on food products is mandatory according to Regulation (EU) N. 1169/2011; therefore, the development of suitable and specific analytical methodologies is advisable. The aim of this study was to perform a multi-allergen real-time PCR system that works well in fast mode at the same annealing temperature and with the same thermal profile. The real-time PCR was developed designing new, specific, and efficient primer and probe systems for the 2S albumingene for sesame and pistachio and for the vicilin precursorgene for macadamia nut. These systems were subjected to a robust intra-laboratory qualitative validation process prior to their application, by DNA extraction and fast real-time PCR, on some real market samples to reproduce a potential allergen contamination along the food chain. The developed system results were specific and robust, with a sensible limit of detection (0.005% for sesame; 0.004% for pistachio; 0.006% for macadamia nut). The performance and the reliability of the target systems were confirmed on commercial food samples. This molecular approach could be used as a screening or as a support tool, in association with the other widespread monitoring techniques (such as ELISA).

Salmon esh spoilage can be greatly reduced through the use of preservation methods, using natural products combined with low temperature and packaging. Microbiological and physicochemical characteristics of fresh salmon llets (Salmo salar), sprayed with an aromatic vinegar and stored in modi ed atmosphere packaging, were investigated. Fillets were kept at 4°C and sampled after 2 h and 3, 7 and 10 days. An untreated control group was used as well. Fish samples were analysed for microbiological (total viable count, Enterobacteriaceae, psychrotrophic microbial count, Pseudomonas spp.) and physicochemical (pH, colour, total volatile basic nitrogen, and biogenic amines) properties. Aromatic vinegar was found to bene cially contribute to the hygienic quality of the salmon, reducing microbial growth during storage and exerting a positive effect, mainly on psychrotrophic loads and Pseudomonas spp. The treatment had a positive effect on biogenic amine levels, showing lower values for histamine, putrescine, cadaverine, and tyramine.