The Impact of Salinicoccus roseus and Heat Treatment of Salt on the Shelf Life of Cured Sciaenids (Johnius dussumieri Dussumieri's Croaker)

Abstract

ABSTRACT Salinicoccus roseus is the most commonly occurring bacterium in salt-cured fish having red discoloration. In the present work, sterile crystalline salt and semiground salt were inoculated with 6 logs level of this bacterium. Half of each of the salt batches was heat-treated at 80°C for 30 min in order to inactivate the inoculated bacteria, while the remaining halves were used as positive controls. The four salt qualities were used in curing of sciaenids (Johnius dussumieri or Dussumieri's croaker). Red discoloration, bacteriological, physical, and biochemical quality parameters were monitored at quarterly intervals for 1 year. The control sciaenids were discarded at the end of 3 mo due to complete red discoloration. The heat-treated crystalline and semiground salt-cured fish were free from red discoloration for 6 and 9 months of storage, respectively. The quality degradation, measured as increases in total volatile nitrogen (TVN) and peroxide values (PV), was also considerably slower in fish cured with heat-treated salt than in the control. Furthermore, the development of TVN and PV values was significantly slower in fish cured with heat-treated semiground salt than in fish cured with heat-treated crude salt. The present study revealed that using heat-treated solar salt to cure fish enhances shelf life 6 to 9 months longer than that of the control.