Photo: Royal Greenland

Maths is a main ingredient in salt-reduced fish products

Monday 14 May 18


Paw Dalgaard
DTU National Food Institute
+45 45 25 25 66


Niels Bøknæs
Royal Greenland
+45 22 24 82 99

Mathematical models from the National Food Institute have been used to develop the recipes for a new range of fish products that contain less salt and more taste.

According to the dietary recommendations from the Danish Veterinary and Food Administration it would benefit the health of Danes if they ate less salt and more fish. For people with a taste for preserved fish products—such as prawns in brine or smoked salmon—a number of new salt-reduced products makes it easier to have their fill, while at the same time complying with both dietary recommendations.

The new products were created in cooperation between researchers from the National Food Institute, Technical University of Denmark, and Royal Greenland as part of a project funded by the Green Development and Demonstration Programme, GUDP. 

Modelling predicts bacterial growth

Salt has traditionally been used to preserve many types of fish products, because it inhibits bacterial growth and increases product shelf-life. Therefore, if manufacturers decide to change the salt content, it can affect the growth of bacteria, which can make the food go off or make it unsafe to eat.

In the GUDP-project, researchers from the National Food Institute have developed models that can predict, how a recipe change will affect the growth of Clostridium botulinum and pseudomonas bacteria in lightly-preserved fish products. 

The models can be used in conjunction with the institute’s existing Food Spoilage and Safety Predictor (FSSP) programme, which predicts the growth of the disease-causing microorganism Listeria monocytogenes as well as lactic acid bacteria, which can spoil the products.

Cheaper product development

The project has given Royal Greenland’s product developers the ability to predict how a change to the recipe will affect bacterial growth in a product. As such they are able to quickly develop new and safe products, because they do not have to spend time on costly product trials.

Instead, they have used the information provided by the models to make adjustments, until they have developed the recipe for a tasty product that is also safe to eat.

Royal Greenland have for example managed to develop coldwater prawns in brine and pasteurized lumpfish roe that contain 40% less salt.

During the project the company has developed 37 new, lightly-preserved fish products, which have acquired the Nordic Keyhole label.

Read more

Since the FSSP-programme was introduced in 1999 more than 10,000 people from companies, institutions and authorities in more than 100 countries have used it. The programme was developed by Professor Paw Dalgaard at the National Food Institute and is freely available. A new version will be released during 2018.

Read more about the programme on FSSP’s website.