Effect of Handling or Processing Treatments on Storage Characteristics of Fresh Spiny Dogfish

Title	The Effect of Handling or Processing Treatments on Storage Characteristics of Fresh Spiny Dogfish, Squalus acanthias
Article Written by	Elinor M. Ravesi, Joseph J. Licciardello, Bette E. Tuhkunen, Ronald C. Lundstrom
Published Date	1985
Fish Species	Spiny dogfish (Squalus acanthias)

What the research is about

This investigation has determined the spoilage pattern and iced-storage life of spiny dogfish (Squalus acanthias) and shows how its storage life might be affected by such handling practices as:

1) gutting and/or bleeding the fish immediately following removal from the water
or
2) holding these fish at other than the ideal iced temperature.

Well-iced dogfish have a shelf life of about ll-12 days. If gutted immediately, the shelf life can be extended about 4 days. Despite their high urea content, ammonia formation does not seem to be a problem in well iced dogfish. However, at elevated temperatures (46.4° and 57°F), ammonia formation is much more rapid and drastically shortens the species’ shelf life. A self-contained kit for quick and simple field estimation of ammonia in Dogfish flesh was found useful.

Research conclusion

The shelf life of properly handled and iced spiny dogfish is comparable in length to that of properly iced gadoid fishes. Despite the high urea content of dogfish, ammonia formation does not account for quality losses during the first 2 weeks of iced storage. The process of bleeding and/or gutting seems to help extend the shelf life of iced dogfish. Abusive handling practices which allow this species to remain at elevated temperature (> 32°F or O°C) hasten ammonia formation. For processors to assess ammonia levels in dogfish intended for export, a rapid and simple field test method is needed and a self-contained kit similar to the one we tested may prove useful.