New results demonstrate the challenge of using the special marine fats phospholipids for enrichment of foods. A PhD project at the National Food Institute, Technical University of Denmark, has shed light on the usability of marine phospholipids for food enrichment.
Marine fats phospholipids contain a high concentration of the omega-3 fatty acids EPA and DHA, which have health-promoting effects on humans. This makes them interesting from both a commercial and research perspective. In her PhD project, Henna Lu Fung Sieng, postdoc at the National Food Institute, produced results which stress the need to develop new methods to improve the quality of commercial marine phospholipids.
New methods to improve fats
As distinct to fish oils, which are so-called triglycerides and reside in the fat deposits of fish, phospholipids reside in the cell membranes of fish, and, thus, have to be extracted in a different way. The usability of marine phospholipids for food enrichment has so far been little examined. It is a big challenge to enrich foods with them as they may get rancid and give an unpleasant off-flavour in the foods. Therefore, the food industry is very interested in methods which delay or stop the rancidity process.
With this PhD project, the most important factors which affect rancidity resistance in marine phospholipids have been identified. On some points the rancidity process differs from those processes which happen in fish oils. For instance, other types of breakdown products are formed as a result of rancidity both during extraction of the marine phospholipids and during their subsequent storage.
Unlike fish oils, the quality of which has improved significantly in recent years, there is a need to improve the quality of marine phospholipids before they can be used in foods. The thesis findings are very important for the further development of new methods to improve the quality of marine phospholipids. Furthermore, the new knowledge will be utilised in the institute’s further research and development of methods for producing rancidity-resistant marine phospholipids of high quality to the food industry.
In 2013, Henna Lu Fung Sieng received an ’Honored Student Award’ from American Oil Chemist’s Society for her PhD work.
Read more
See Henna Lu Fung Sieng’s PhD thesis: Physico-chemical properties, oxidative stability and nonenzymatic browning in marine phospholipids and their uses in food applications (pdf).
Read more about the National Food Institute’s research in the area of food enrichment with omega-3 on food.dtu.dk.