Photo: Royal Greenland

Mathematics for healthier fish products

Food, fish and agriculture Food safety Food production Mathematical modelling
Mathematical models from DTU are being used to develop new fish products with less salt and more flavour.

According to official Danish dietary recommendations, eating less salt and more fish will benefit the health of Danes in general. For people who enjoy eating preserved fish products—such as prawns in brine or gravlax—a number of new salt-reduced products are making it easier for them to satisfy their cravings while following both dietary guidelines.

The new products have been developed through collaboration between researchers from DTU Food and Royal Greenland as part of the Ministry of Environment and Food of Denmark’s Agrifish Agency’s Green Development and Demonstration Programme (GDDP) project.

Modelling predicts bacterial growth
Salt has traditionally been used to preserve many kinds of fish products because it inhibits bacterial growth and extends product shelf-life. Therefore, if producers change the salt content, it can affect the growth of bacteria, which can make the product unpleasant or dangerous to eat.

In the GDDP project, DTU Food’s researchers have developed new models that can predict how changing a recipe affects the growth of Clostridium botulinum and Pseudomonas bacteria in lightly preserved fish products.

The models can be used in conjunction with the department’s existing Food Spoilage and Safety Predictor program http://fssp.food.dtu.dk/, which predicts the growth of the pathogenic micro-organism Listeria monocytogenes as well as lactic acid bacteria that can spoil the products.

Lower product development costs
The project has made it possible for Royal Greenland’s product developers to predict how changing a recipe will affect the growth of bacteria in a product. In doing so, they have been able to more quickly develop new and safe products because they have not had to spend time on costly experiments.

Instead, they have used the knowledge the models have given them to make the necessary adjustments until they have developed the recipe for a tasty product which is also safe to eat.

As part of the project, Royal Greenland has, for example, managed to develop cold water prawns in brine and pasteurized lumpfish roe with a 40 per cent lower salt content.

During the project period, the company has developed 37 new, lightly preserved fish products that have successfully met the criteria for Keyhole nutrition labelling. https://www.norden.org/en/news-and-events/news/keyhole-milestone