Contact
Sigurjón Arason
Chief Engineer
sigurjon.arason@matis.is
Salted fish drying in Icelandic conditions (R13 078-12)
Dried salted fish is a popular consumer product in Southern Europe and Latin America. A considerable amount of the salted fish imported from Iceland is dried in Portugal, before being sold to consumers in that country or transported on to Brazil. There is interest in examining the feasibility of transferring the drying process to Iceland and thus increasing the added value of the product. The aim of this project was to build up knowledge in the production of dried salted fish from Icelandic raw materials, which has been salted and dried under Icelandic conditions using geothermal energy. Furthermore, to develop drying technology that can produce a comparable product and even better than is on the market today. To achieve these goals, experiments were carried out with drying salted fish in an Icelandic lattice cell (pyramid dryer). The effects of drying on different types of fish, which were processed by different salting methods and treatment before drying and during drying, were compared. The results showed that there was a difference in the drying rate between fish species (ling, cone and cod). There was also a difference between brine which was brine salted and cod which was brine and injected with Carnal phosphate. No weight difference was measured between pickled fish, with or without phosphate from the same producer in drying. Some benefits in the form of faster weight loss during drying were achieved by loading the fish during drying. The temperature and humidity in the drying chamber were very stable and there was no significant difference in the drying speed in the fish, located in different places in the chamber. The results of measurements of water and salt content in different places in fish flesh showed the lowest water content on the surface of the fish after drying.
Dried salted fish is a popular consumer product in Southern Europe and South America. Large quantities of salted fish export from Iceland are further processed into dried salted products in Portugal, before consumed in Portugal or exported to Brazil. By drying the salted fish in Iceland an added value could be achieved, before export. The aim of the project was to build up expertise in the production of dried salted fish from Icelandic ingredient, using geothermal energy. Furthermore, to develop a drying technology which can produce a similarproducts and even better that is on the market today. To achieve these objectives, attempts were made by drying the salted cod in Icelandic, grid cell (pyramid dryer). Fish of different species, different salting methods and treatment for drying and during the drying period, were compared. The results showed significant difference in drying rate between fish species (ling, tusk and cod). Also there was a difference between cod which was picle salted and brined cod injected with Carnal phosphate. No differences in weight loss was observed between brined cod, with or whitout phosphate, from the same producer. Some advatages can also be achieved by compressing the fish during drying, which speeds up the weight loss. The humidity and temperature in the drying tunnel were stable and no difference could be found in drying rate of fish in different locations in the drying tunnel. Results from water and salt content in different locations in the fish, showed the lowest water content on the surface of the fish after drying.