So far, Danish red and black currants have been used mainly for jams and juices. However, a research trial with new varieties of red and black currants and gooseberries has led scientists at Aarhus University to conclude that the berries have the potential to be grown as a luxury item that can be eaten fresh as snacks or used for decorating cakes and food.

The scientists behind the project have been working on developing a new production method for growing blackcurrant, gooseberries and redcurrants and it has produced good results.

- The yields and sizes of berries tell us that with the right production methods and varieties there is a potential for fruit growers in growing berries for fresh consumption, explains senior scientist Lillie Andersen, who was in charge of the research project "Luxury berries for fresh consumption".

New cultivation method

The production method that scientists have been working on since 2009 consists for the blackcurrant bushes of taking two to three main stems and growing them along wires into an 1.8 m high espalier. The purpose is to give the leaves as much light as possible and to grow uniform berries that are easy to harvest.

One of the challenges of this production method is that the currant bushes have many "sleeping" shoots, which are activated. Therefore, new growth from the bottom has to be removed several times during the season.

The blackcurrants in the project were drip-irrigated and grown in polytunnels in pots or in conventional and organic soil. The organic cultivation caused problems with yield, which in several cases was only half that of the conventional production.

- For the organic production the price of the berries will be relatively high. In some years, the yields can be low and in other years they will be the same as in the conventional production. The problem is particularly with aphids, but there is a new remedy on the market to control aphids in organic farming which looks promising, says a hopeful Lillie Andersen.

Mild and robust variety selected

Of the blackcurrant varieties available, the scientists chose Narve Viking because of its mild flavour and particular resistance to fungal diseases and also its suitability for organic cultivation. Another variety selected was Big Ben, which impressed with its large berries.

- Big Ben has a potential that is worth exploring further so that the variety may be marketed, states Lillie Andersen.

Of the redcurrant varieties available the choice fell on Rovada because of its long fruit clusters and intense berry colour. In the experiments the redcurrants grew well both in polytunnels and in the field and there were no differences in total yield. There were, however, differences in the number of berries:

- The number of flowers on the stalk that develop into berries is significantly larger when grown in pots in the polytunnel than in field soil, but the berries are consequently smaller. This difference could be caused by differences in pruning or in watering frequency, says Lillie Andersen, who also pointed out that plants in pots should be watered frequently to avoid dehydration.

The scientists believe that the findings from the research can form the basis for a burgeoning production of fresh berries, not least because the berries have lots of good qualities.

- The berries have high contents of anthocyanins and vitamin C, which makes them suitable as healthy sweet snacks. We suspect that the berries can become a hit with consumers, as there is a surge in the interest in Nordic food and consumers also demand healthy products that are produced under controlled conditions, explains Lillie Andersen.

Growers take new knowledge on board

She is aware of one grower so far, who grows berries using the new production system developed. And at the same time, the search continues for the most suitable berry varieties.

- We are continuing to study some large-berried blackcurrant varieties and some virtually thornless and hairless gooseberry varieties, she says.

Further information: Section leader Lillie Andersen, Department of Food Science, telephone: +45 8715 8323, mobile: +45 4029 2142, e-mail: lillie.andersen@agrsci.dk