Effect of fish freezing on selected parameters of smoked product quality

In the circumstances of small processing facilities for smoked fish production, and a particularly good fishing season, there occurs the necessity for freezing the catch in order to process it and preserve it in this way, at times when the season is not so good. To this end, the goal of our research was to examine the effect of freezing fish on the selected parameters of cold smoked, vacuum-packed trout fillets. To conduct the experiment, two groups of trout were formed: the control one, out of fresh fish, and the experimental one, out of previously frozen fish. In the course of a three week period of smoked fish storage at the temperature of 4ºC the variation of the total number of bacteria, and the total number of lactobacilli were monitored. Also, at the end of processing, the content value of water and salt were determined, as well as the content value of salt in the water phase, and aw value (water activity). By testing the bacteriological status of two groups of products during the storage period, it was determined that the total number of both bacteria and lactobacilli was smaller in the samples produced from frozen fish. The average content value of water and NaCl, as well as the salt content value in the water phase, in the vacuum-packed, smoked fillets produced from frozen fish was statistically, considerably larger than the content value of water, salt, and salt content value in the water phase in the samples manufactured from fresh fish. Our research findings show that using the raw material that was previously frozen for producing smoked fish fillets is not only appropriate, but also recommended