Why are some tomatoes so tasteless? It's due to disregarded seasonality, yes, and long, chilled shipments (both of which destroy flavor), but plant geneticists have discovered an imbedded source: the gene mutation that makes tomatoes bright red, and which was deliberately bred into tomatoes by plant breeders, is now known to to stifle the gene that makes tomatoes tasty! So red tomatoes = tasteless tomatoes. Who knew?
The study, recently published in the journal Science, reports that the gene inactivated by the make-it-red mutation is actually the one responsible for providing the sugars and sweet smells that accompany the best tomatoes. Ann Powell, a plant biochemist at the University of California, Davis and the lead author of the Science paper, put weed genes into tomato plants, and was surprised when the tomatoes with the genes turned dark green right before ripening, rather than the pale green of most tomatoes. The green color comes from chloroplasts, the "factories" in plant cells where photosynthesis takes place and converts light into sugar which the plant uses use for food. The weed gene, she discovered, was effectively replacing a disabled gene in a tomato's fruit, and turning it dark green.
The researchers used genetic engineering to turn on the disabled genes while leaving the uniform ripening trait alone. The fruit was evenly dark green and then red and had 20 percent more sugar and 20 to 30 percent more carotenoids when ripe.
Of course, since this was a science experiment, the scientists were unable to actually taste the tomatoes. However, the higher sugar content seems to suggest better flavor. But even if this is true, don't expect to see genetically engineered tomatoes on store shelves anytime soon. (Producers would never make it for fear of alienating customers.) The workaround? Heirloom and wild specie tomatoes that have not been bred with the uniform ripening mutation. So that's why they taste so much better!
Read More: Flavor is Price of Scarlet Hue of Tomatoes, Study Finds at The New York Times
(Image: S. Zhong and J. Giovannoni via The New York Times)
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I don't think the evidence supports the assertion that producers will avoid genetically engineering our food. They tend to simply restrict labeling to hide the fact as best they can.
Because they're red? Isn't that a bit misleading? After reading the article in Science, it sounds like the reason is because they are light green before before ripening rather than dark green or maybe I'm just confused.
@Livia O - this post oversimplifies the story quite a bit. It's not just that they're red, its that they ripen uniformly red. A lot of the best tasting tomatoes tend to have uneven coloring, and sometimes still have a bit of a dark green tinge even when completely ripe. Some of the best tasting tomatoes are the "purple" varieties which aren't really purple, but more of a dark red/brown with a little green in the skin.
I highly recommend the book "Tomatoland" which talks about the tomato industry mostly in Florida. Corrupt. Whatever just happened to growing a tomato?!
At least someone answered the question ( I had no idea of the "gene mutation") I've being asking for years and years. Even for those lovers of the so called field tomatoes, I would argue they're still tasteless. And cheers for the recommendation of the Heirloom tomatoes - my favorites one).
I've had some locally grown plum tomatoes that were a beautiful deep red that were, by far, the best tomatoes I've ever tasted. I've never been a big fan of raw tomatoes, but these completely changed my mind. I was adding them to a salad and kept sneaking bites as I chopped them! I think it depends where the tomatoes come from and how they're grown. Aren't most conventional tomatoes picked green, shipped green and treated with some sort of gas to artificially ripen them? Thought I read that somewhere.
@indycote
For long shelf-life tomatoes are often picked green and later treated with ethylene to make them "ripen", but because the ripening process is effectively stopped, it only converts the remaining starch into sugars. The complex flavours can't develop because there aren't enough substrates for the enzymes to work on. That's why vine-ripened tomatoes always taste better than the ones ripened off the vine.
I thought everyone knew this. My mom has always told me that tomatoes don't taste like they used to, and that it's because they've been modified to be pretty and ship well. I never knew what she was talking about until I moved to a big city with a fancy grocery store. There I discovered heirloom tomatoes, and I have the fear that all our food will one day be tasteless like tomatoes.