Make tomatoes tasty again: Scientists discover ‘flavour genes’ in the world’s most valuable fruit

Mass produced commercial tomatoes contain increasingly less flavour and return increasingly less consumer satisfaction. A team of researchers has discovered a ‘genetic roadmap’ for rebreeding tastiness into tomatoes

The study, published in Science, analysed the genetic composition of 398 modern, heirloom and wild tomato varieties.

A consumer panel then identified different chemicals playing the greatest role in flavour and satisfaction.

Chinese, American, Spanish and Israeli scientists collaborated on the research.

Dr. Sanwen Huang, a researcher at the Chinese academy of agricultural science (CAAS), told FoodNavigator: “We discovered that 13 chemicals are significantly lower in modern tomatoes than older varieties.

“The gene which produced this chemical had been lost because for years selection has focussed solely on factors like yield or weight or disease prevention.

“Discovering which genes and chemicals produce flavour requires knowledge and technology that is not available for breeders. This has contributed to a lack of flavour selection in the history of tomato growing. Now we know which chemical contributed to flavour and we have the genetic loci (the genetic area) to contribute, so we are on the road to discovering the genes themselves.”

By analysing the composition of both modern tomatoes bred for mass consumption, and older 'heirloom' and wild varieties, the researchers could identify which potential genes can be selected in future. Utilising this discovery without sacrificing the capacity for growing en masse, in particular sizes, will be the next phase of research, added Dr. Huang. 

“We cannot sacrifice yield, weight, disease prevention and so on, and now we need a more comprehensive approach which integrates the knowledge of which genes control each of these factors. This will take a huge collaboration between geneticists, bio chemists and consumers.

One major hurdle in the way of creating flavoursome tomatoes has also been overcome:

“Sometimes they are not compatible – selection of bigger fruits always has a negative impact on the sugar content; but perhaps we can find a gene that increase sugar content without sacrificing too much yield. There are also two acids – malic acid and citric acid, bad and good for flavour respectively. However we have now found genes which control these acids separately, so we can maintain citric acid levels whilst dropping the bad tasting malic acid" said Dr.Huang. 

The results are open to the public and the researchers are not seeking intellectual property rights, so the next phase of development is now ready for development in Europe. 

Dr. Huang said:“There are already major tomato breeding companies in the US and China which are very interested in taking advantage of our research, but the results are open to the world. We are not interested in protecting our technology, and we would be happy to collaborate with any company willing to help develop the research. My lab is open.” 

Tomatoes 

The tomato the highest value fruit and vegetable crop globally. 

EU exports make up the bulk of the world tomato market, contributing over €3.5 billion worth in 2015. The Netherlands, Spain, France and Belgium all rank in the top ten exporters worldwide, with Dutch produce falling just short of Mexico’s €1.8 billion annual export – the largest in the world.

The EU also falls just short of China, the world's largest tomato producer, by growing 16.0 million tonnes per annum from an area of almost 289,000 hectares. 

Source: Science 

Published 2017, DOI: 10.1126/science.aal0659

"A chemical genetic roadmap to improved tomato flavour"

Authors: Sanwen Huang, Harry Klee et al.