Title: Effect of chilled temperature and salt concentration on shelf life of Herring (Clupea harengus)

Keeping the quality of fish and fish products at its best is the most important issue in fish processing. Based on the trend demanding that salted fish reduce salt content for dietary reasons as well as for further processing, this project focused on the extension of shelf life by investigating quality changes during brining in the cold storage of herring (Clupea harengus), the one of the popular foods in DPR Korea. Instead of the traditional salting method, an innovative method has been suggested called cold brining. Cold brining is a processing method expected either to provide a good salty flavour or to extend shelf life for further products by delaying microbiological growth and the chemical changes of the co-operation of ice and salt. In both experiments using fresh whole herring and fillets, five different brine concentrations of 8, 12, 14, 16 and 18%, and five different temperatures of 2, -1, -2, -4, -8 and -24 °C were used for 25 and 18 days, respectively, to select the optimum conditions for cold brining. The results were revealed that the 14% brine at -8 °C can be regarded as optimum condition for pre-cooling of herring. The cooling time will take about 20 minutes in the brine, in which the ratio of fish to brine is 1:2. The cold brining of herring should be done with a mixture of salt and brine. The amount of salt is 10% to the weight of raw fish and the ratio of fish to brine is 1: 0.2.