Aarhus University Seal / Aarhus Universitets segl

Natural berry pigments as food ingredient at the heart of new project

Scientists from Aarhus University, the University of Southern Denmark and a number of corporate partners are exploring how to effectively extract natural food colours from aronia berries, blackcurrants and sour cherries. The goal is to create a new, natural alternative to artificial food colours.

[Translate to English:] aronia, aronia-bær
[Translate to English:] Forskning indikerer, at aroniabær kan have en sundhedsmæssig gevinst, der kan udnyttes ved at bruge udtræk fra bærret som farvestof. Foto: Martin Jensen

We have heard it before: We eat with our eyes. That is why food colouring is so important. However, both consumers and the industry have a strong desire to replace artificial colours with a natural alternative.

In a new project, scientists from the University of Southern Denmark and the Department of Food Science at Aarhus University will look at the possibility of extracting the red pigmentation from aronia berries, black currants and sour cherries and using it as a natural colouring in food products.

- Research shows that artificial colours may, for example, make children hyperactive, and consumers are therefore increasingly asking for natural ingredients in food. Our hope is that we can create a more accurate knowledge base for how to produce these colours. Basically we need knowledge on the optimal production of raw materials, on improving fruit processing  and colour extraction methods and on the relationship between quality, price and yield. This knowledge will then be passed on to the industry, so we can nudge the production up a gear, explains Martin Jensen, Senior Researcher at the Department of Food Science at Aarhus University.

Double-up benefit

The project looks at all the stages of the value chain - from production to processing and to the storage of the concentrated colours. In addition to the two universities the project also involves the fruit growers Danfrugt Skælskør A/S and Elkærholm and the ingredient manufacturer, Chr. Hansen A/S.

The project specifically aims to utilise the leftover pulp from conventional juice production. This residue often contains highly dense pigmentation that is lost when the pulp is discarded or spread onto fields.

- We can actually get two products out of a single berry production and therefore overall more value and a better economy. In this way the request  byf people who prefer a natural product are matched with the surplus pomace resource. The challenge is to effectively extract the colour in quantities and qualities that make it suitable for use in food products, says Martin Jensen and explains that the focus is particularly on aronia berries because they have a four to fivefold higher colour density than blackcurrants and sour cherries.

- At the same time research suggests that aronia berries have some health benefits that could be utilised in food. The berries are also fairly easy to grow and are rarely attacked by disease or insects. There isn’t the need to spray as much and there is the possibility to ultimately create an organic production, says Martin Jensen.

Since there are currently only about 40 hectares planted with aronia berries in Denmark, scientists have chosen to also include blackcurrant (1900 ha) and sour cherries (1329 ha) in the project to assess the promise of these species.

Large future potential

The two university partners have different roles and expertise in the project. Where the University of Southern Denmark primarily focuses on identifying the most effective methods of extracting and purifying the colours, Aarhus University and the commercial partners have the job of characterising the optimal berry and pomace quality, how this can be cultivated and how different fruit pressing methods for juice production affect the quality of the leftover pomace .

Scientists from Aarhus University will also be characterising the biochemistry of the pigments. This involves describing the anthocyanin profile and its dependence on  pressing processes and berry species, characterising the taste and exploring how, for example, heating and acidity affect the colour.

- It’s important that we know exactly what happens to the colours when they, for instance, are pasteurised. The colours can also change a lot depending on the general acidity of the food commodity. SDU will extract the anthocyanin colours in pure form and we can find out how a particular anthocyanin colour tastes, says Martin Jensen, pointing out that much of the knowledge generated in the project will be used to analyse how to ensure  the highest quality of the delivered product.

The project is, in other words, clearly targeted the commercial sector – with benefits both for Danish growers and the manufacturers of ingredients. Growers will have a unique opportunity to establish themselves as suppliers to the food colour industry, while the Danish food ingredients industry will have new, proven raw materials that can be used as natural food colours.

- The international market for food colours is huge and Denmark is already a strong player in this market. The market is expected to grow in the future and a Danish high-value product based on sound ingredients and a significant knowledge input should give us a competitive edge internationally. It is therefore imperative that we get the results of our research conveyed out to the industry. This is precisely what this project enables us to do.


Project leader  is Associate Professor Birgir Nordahl from the University of Southern Denmark. Martin Jensen is project leader at Aarhus University. A postdoc will also be attached to the project at AU.

For further information please contact:

Senior Researcher Martin Jensen

Department of Food Science, Aarhus University

E-mail: Martin.Jensen@food.au.dk,

Telephone .: +45 87158331