Tomatoes can have a combination of sweet, sour, salty, savory and slightly bitter taste. But now this fruit may have a new twist. Scientists from Brazil and Ireland have been researching how to make tomatoes contain the taste of chili peppers.
In an opinion paper, published in the journal, Trends in Plant Science, researchers presented a new gene editing technique that could make tomatoes spicy. However, their aim is not just for the sake of spicy tomato sauce. The genetically engineered spicy tomatoes may have potential industrial and medical uses.
How to Spice it up
There is no need to transplant new genes. The method they found to make tomatoes spicy is by activating the capsaicinoids hidden in their genes. Capsaicinoids are the reason behind the spiciness of chili peppers. They are only produced by species of plant from the Capsicum genus, also known as hot peppers.

According to the researchers, tomatoes still have the machinery to make capsaicinoids. Tomatoes and peppers were only split off from the same evolutionary tree branch about 11-20 million years ago. In evolution, that period of time is not considered long.
“The tomato has the genes… you just need to activate them in the right order in the right places,” said Agustin Zsögön from the Universidade Federal de Viçosa in Brazil and one of the authors of the study.
Why Spicy Tomatoes?
Does it really need to be spicy tomatoes? Why not make spicy potatoes or astringent tomatoes? The idea of the research is to make tomato a factory for producing capsaicinoids.
Aside from the fact that the tomato itself already has capsaicinoids genes, tomatoes are good subjects because they are easy-to-control model organism. They have been used to many other gene engineering studies.
On the other hand, hot peppers, the only producers of capsaicinoids are hard to cultivate. If spicy tomatoes are produced, they would have a yield capacity which is 30 times higher than chili. This would be a great boon for industries which uses capsaicinoids such as medicine. Capsaicinoids are commonly used in low-risk painkillers.
“The proof of concept here is that we can transfer the unique thing endemic to a less-produced plant into another plant that is more widely produced,” said Lizaro Perez, co-author of the study and Professor of Plant Physiology at the University of Sao Paulo, Brazil.
Almost There
To activate the genes, the researchers need to use gene-editing tools like TALENs or the well-known CRISPR/Cas9. However, the whole process still needs more study. The researchers pointed out that the gene-editing might unintentionally affect other genes in the tomato.
Hopefully, in a few years, spicy tomatoes might be available on our dining table.