Monitoring the quality and shelf life of crustaceans with commercial interest by the HSC70 protein

Within the DeCroMed Project, we used a multi-parametric approach to study the quality of the shrimp Parapaeneus longirostris, and the lobster Nephrops norvegicus, during post-thawing periods. Nowadays, there is a lack in the knowledge of the changes taking place during handling, processing and storage of crustacean species of commercial importance caught in the Mediterranean Sea. The aim of this study wasto obtain detailed information, especially at the biochemical level, on the crustacean post mortem changes occurring after thawing procedures aimed at monitoring crustaceans freshness and shelf life over time.We measured the water-holding capacity of P. longirostrisand N. Norvegicusmuscles and monitored changes in pH, protein content and composition of muscle exudates obtained from each specimen by centrifugation. In addition, we evaluated the levels of a few candidate marker proteins chosen from a list of biological markers validated to predict the quality of food products. We found that HSC70 protein levels are negatively related to: i) the increase of the water-holding capacity, ii) the formation of protein aggregates and protein degradation, iii) the pH of muscle exudates, and iv) the flesh softening of the crustacean muscle. Inconclusion, we propose the HSC70 protein as a biomarker of crustacean freshness. Further studies are underway to identify additional biomarkers to evaluate the thawed crustacean quality. Work fully supported by PO-FESR 2007-2013 - SICILIA- DeCroMed "Pescato Mediterraneo: certificazione di qualità e valorizzazione dei crostacei decongelati"; Linea di Intervento 4.1.1.1, GURS 28/10/2011,year 65, N° 45; CUP: G93F12000190004. Authors acknowledge the technical assistance of Mr. Mauro Biondo.