Geneticists Think They Can Fix Tasteless Tomatoes

By identifying the genes that control the production of volatile chemicals, we could soon turn the bland tomato’s flavor back on

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Dan Iggers

Ah, the modern tomato: big, bright, deliciously red on the outside…pale pink and bland on the inside. More water than juice, more spongy than meaty. Bred to survive the long trip from field to truck to store to fridge without bruising and to produce high yields. The main casualty of the selection process that brought us these benefits? Taste.

John Timmer for Ars Technica writes:

In the words of a panel at the meeting of the American Association for the Advancement of science, we “broke” the tomato by allowing the plant breeders to respond to the needs of farmers, instead of the tomato’s end-users: consumers. As a result, their breeding has produced a product that most people don’t actually enjoy eating.

The perceived flip-side of the tomato world are the so-called “heirloom” tomatoes, the varieties grown and bred before more recent tinkering. Differentiating heirloom tomatoes from each other and from the modern bland strands, says Scientific American, are only a few specific genes.

eirlooms are actually feeble and inbred—the defective product of breeding experiments that began during the Enlightenment and exploded thanks to enthusiastic backyard gardeners from Victorian England to Depression-era West Virginia. Heirlooms are the tomato equivalent of the pug—that “purebred” dog with the convoluted nose that snorts and hacks when it tries to catch a breath.

“The irony of all this,” says Steven Tanksley, a geneticist at Cornell University, “is all that diversity of heirlooms can be accounted for by a handful of genes. There’s probably no more than 10 mutant genes that create the diversity of heirlooms you see.”

According to Scientific American, some of the downsides of both heirlooms and tasteless tomatoes could be undone through tomato hybridization—of mixing heirloom and highly-productive, hardy modern tomatoes.

And, even if totally new strains of super-productive, tasty, tangy sweet tomatoes can’t be fashioned through selective breeding programs, says Timmer, scientists might still be able to fake it.

A lot of our experience of flavor really does come from smell, but not from breathing in; instead, volatile chemicals disperse out of the back of your mouth, with some of them reaching your nasal passages. Not only can these volatiles convey a distinctive flavor, but they can also interact with flavors sensed by the tongue, enhancing or suppressing sweetness, saltiness, etc.

From a big collection of modern and heirloom tomatoes, University of Florida horticulturist Harry Klee pulled a list of the different volatile chemicals found in the different tomato varieties. By identifying which genes are associated with which volatile chemicals, scientists may soon be able to selectively turn the bland tomato’s flavor back on.

More from Smithsonian.com:

Learning About Heirloom Tomatoes
A Passion for Tomatoes

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