Marine raw materials and foods
Professor Ingrid Undeland
Bita Forghani, PhD
Mehdi Abdollahi, PhD
Haizhou Wu, PhD
Karin Larsson, PhD
Cecilia Tullberg, PhD
Hanna Harrysson, PhD-student
Mursalin Sajib, PhD-student
Semhar Ghirmai, PhD-student
Anahita Esmaeilian, PhD-student
James Hinchcliffe PhD-student (shared with Gothenburg University)
The overall aim is to add value to underutilized marine raw materials (fish, shellfish, algae) by stabilizing and/or isolating valuable components such as lipids, proteins and antioxidants. Marine lipids are mostly known for their high content of long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA, or “omega-3”) which have been demonstrated to prevent e.g. cardiovascular diseases. Unfortunately, LC n-3 PUFA are very prone to oxidation which results in negative quality changes (rancidity) and a concomitant loss of nutritional value. When it comes to marine proteins, these have a high level of essential amino acids, and also have excellent technical functionality, which are strong incentives for finding new sustainable sources of marine protein, beyond the classic fish fillet.
The marine research group participates in several projects on lipid oxidation in fish on national, Nordic and EU basis. Important research questions have for instance been the relation between compositional differences caused by geography, season or processing method, and development of lipid oxidation in herring and mackerel. Other projects have addressed how natural antioxidants from plants, or from the fish itself, can prevent the development of lipid oxidation in seafood. Currently, a major focus area are fish hemoglobins, which are key catalysts for lipid oxidation in fish, and also are important for unwanted colour changes of seafood. We are currently investigating new strategies for hemoglobin-removal, with the aim to apply them during the early steps of the fish processing chain. In another project, oxidation of marine lipids during the gastrointestinal (GI) passage is investigated. In vitro, we have seen that reactive aldehydes can develop from both fish oils and fish during gastric and intestinal conditions. This could affect the beneficial effects of LC n-3 PUFA, something is investigated in an intestinal cell model. Different ways of preventing GI lipid oxidation are also under consideration.
On the marine protein side, we have several projects addressing how these can be isolated from complex raw materials like whole fish, fish by-products or algae, using the so called ”pH-shift method”. Protein extracts are then characterized on a molecular level, but also out from their technical functionality (gelation, emulsification etc.), nutritional profile and bioavailability. In another category of projects, we focus on recovery of proteins from seafood process waters, and a series of different concentrating methods are evaluated. Also here, recovered proteins are investigated out from molecular, nutritional and technical aspects. Many of these projects are carried out in close collaboration with industry.