On Wednesday, 10 December 2025, Carina Eveline M. Pina Fernandes defended her doctoral thesis in Food Science at the Faculty of Food Science and Nutrition at the University of Iceland. The thesis is entitled: Product Development of Atlantic Mackerel (Scomber scombrus). Effects of Hot Smoking and Canning.
The opponents were Dr. Heidi Nilsen, Research Director at Nofima in Tromsø, Norway, and Dr. Santiago Aubourg, Research Professor at the Spanish National Research Council (CSIC) in Spain.
The supervisors were Dr. María Guðjónsdóttir, Professor, and Sigurjón Arason, Professor Emeritus. Also serving on the doctoral committee were Dr. Hildur Inga Sveinsdóttir, Lecturer, and Dr. Tumi Tómasson from GRÓ – the Fisheries Training Programme.
Dr. Ólafur Ögmundarson, Associate Professor and Head of the Faculty of Food Science and Nutrition, chaired the ceremony, which took place in the Ceremonial Hall of the University of Iceland.
Abstract
Spjallmenni The research aimed to examine the characteristics of mackerel caught in Icelandic waters while feeding, and whether it is suitable as a safe and appropriate raw material for ready-made fish products for both the Icelandic and international markets. The effects of various processing methods, such as brining, freezing and frozen storage, were investigated, with an emphasis on the development of hot-smoked and canned products. These methods were selected due to their well-known effects on food safety, shelf life and storage solutions.
The shelf life of the hot-smoked products under refrigerated storage reached at least 21 days, whether the fillets were processed from fresh or frozen mackerel. Since the difference between fresh and frozen fillets was minimal after hot smoking, and the products remained stable under refrigerated storage, frozen fillets can readily be used for the production of hot-smoked mackerel fillets year-round.
The effects of freezing mackerel fillets before or after hot smoking were examined in canned products. The quality effects of different filling media (liquid in the can) during canning were also investigated. Canning ensured the stability of the hot-smoked mackerel fillets during storage at room temperature for up to 12 months, and no L. monocytogenes was detected in the products.
The research demonstrated that the fatty Atlantic mackerel found in Icelandic waters can be well utilised, not only for the production of fishmeal and fish oil, but also for the production of higher-value products for human consumption through the development of hot-smoked and canned products. Frozen fillets offer the opportunity to utilise the raw material and process it into high-quality products year-round.