Combined effect of O2 scavenger and antimicrobial film on shelf life of fresh cobia (Rachycentron canadum fish steaks stored at 2°C.)

Abstract

The present study was carried out to understand the combined effect of O2 scavenger (OS) and antimicrobial film (AM) in extending the shelf life of fresh cobia (Rachycentron canadum) fish steaks stored at 2^0 C in a plastic pouch of multilayer film of ethylene–vinyl alcohol. The chitosan based film containing ginger essential oil as an active antimicrobial agent was used as primary wrap for fish steaks. During storage, a significant (p<0.05) reduction in the rate of total volatile base nitrogen formation and lipid oxidation as indicated by thiobarbituric acid value was observed for fish steaks wrapped with antimicrobial film and packed with O2 scavenger (OSAM). There was a lag phase of 5 days observed for total mesophilic count of OSAM compared to control sample. The limit of 7 log cfu g-1of total mesophilic count was exceeded by control sample on 15th day of storage. OS application significantly reduced the growth of aerobic Pseudomonas spp. and AM film showed good inhibition against lactic acid bacteria and Brochothrix thermosphacta. Sensorily, the OSAM cobia steaks was acceptable up to 30 days compared to 15 days for samples in the control pouch.