This could have a positive development on tomato-based foods, which are increasingly positioning themselves at the healthy end of the market.
Tomatoes are a major source of nutrients in numerous cultures. In 2004, 120,000 tonnes of tomatoes were harvested worldwide - and every year this number increases.
Numerous medical studies have shown the health value of tomatoes. Lycopen, the pigment that makes tomatoes red, can for example prevent heart disease. Tomatoes furthermore contain a lot of vitamins C and E, indispensable for human nourishment.
But after centuries of cultivation for shape, colour, and other useful qualities, modern cultured tomatoes tend to be of small genetic diversity in comparison with wild types. This has affected the taste and health value of the fruits.
Now researchers from the Max Planck Institute of Molecular Plant Physiology, in co-operation with Israeli scientists, have identified DNA fragments in tomatoes that make their contents both healthy and tasty.
To cultivate tomato strains with particular characteristics, researchers have to increase the genetic diversity of cultured tomatoes. The researchers crossed wild tomatoes with cultured ones, then investigated the contents and genetic make-up of the hybrid.
The results suggest that tomato growers could use wild tomatoes to produce better-tasting cultured tomatoes. This could be done by either cross-breeding them with wild tomatoes, or changing their genetic make-up technologically.
Scientists from the Max Planck Institute for Molecular Plant Physiology in Golm, and their Israeli colleagues at Hebrew University in Jerusalem, chose the second option. They investigated strains of tomatoes created from the crossing of cultured and wild types. Their goal was to identify the biochemical composition of fruits and determine which factors control their development.
The German-Israeli research team used a method of analysis developed at the Max Planck Institute for Molecular Plant Physiology. The technique - a combination of mass spectrometry and gas chromatography - analyses the composition of biological samples.
The scientists say that this method can be used to quickly and simultaneously look into a fruit's amino acids, organic acids, sugar and vitamins.
The end result was found to be very positive.
"On one hand, we measured higher amounts of essential amino acids and vitamins, on the other hand the fruits showed an altered combination of various sugars and organic acids," said Dr Alisdair Fernie, head of the Institute's Central Metabolism research group.
"These contents have a great influence on the taste of tomatoes."
This breakthrough could therefore led to the development of tomatoes in a more targeted way to make them tastier and even more nutritious than before.