Improved microbial and sensory quality of clams (Venerupis rhomboideus), oysters (Ostrea edulis) and mussels (Mytilus galloprovincialis) by refrigeration in a slurry ice packaging system

The aim of this work was to evaluate a slurry ice (SI) packaging system on three bivalve species: clams (Venerupis rhomboideus), oysters (Ostrea edulis) and mussels (Mytilus galloprovincialis). Comparative analyses were performed on specimens caught in autumn and spring and compared to batches stored in conventional flake ice. Microbiological analysis of autumn specimens stored in SI showed significantly (P < 0.05) reduced numbers of mesophiles and psychrotrophs in all three species, as well as fewer Enterobacteriaceae in clams and oysters. Spring specimens also exhibited significantly (P < 0.05) lower microbial loads, with SI storage significantly (P < 0.05) improving the control of mesophiles, psychrotrophs and proteolytic bacteria in clams and oysters. Sensory analysis correlated well with microbial analyses, with a significantly (P < 0.05) better quality in terms of odour, taste, juiciness, appearance and shelf life. The SI packaging system evaluated in this work proved to be a valuable method for maintaining quality of these bivalve species.