Tuna burgers preserved by the selected Lactobacillus paracasei IMPC 4.1 strain

The use of protective microbial strains in combination with modified atmosphere packaging (MAP) and refrigerated storage on the shelf life of tuna burgers was investigated. Preliminary, the protective ability of three lactic acid bacteria (LAB) cultures (Lactobacillus casei, Lactobacillus paracasei and Lactobacillus plantarum) have been assessed on ready-to-cook tuna fish burgers. Among them, L. paracasei showed the best preserving performance and significantly controlled both aerobic mesophilic bacteria and Pseudomonas spp. growth. Subsequently, the efficacy of the selected LAB culture under MAP conditions (5% O2 and 95% CO2) was assessed evaluating microbial and sensory quality, as well as volatile aldehydes content. Results indicated that the shelf life of burgers containing L. paracasei and packaged under MAP was 4 days longer than the control (shelf life about 6 days) and that the applied procedure represents an effective approach for the mild preservation of fish products.