CNN: How about buying tomatoes 'on the vine.' Does that really influence the flavor of a tomato?
Klee: So the problem here is when you're picking those tomatoes on the vine, you pick them up and you smell them and you do smell something. You're actually smelling the vine and not the tomato itself, so it's really a marketing gimmick. The good thing about those tomatoes that are picked on the vine is that generally they are picked when they're ripe.
CNN: So a lot of the volatiles must develop very late in the ripening process, while the tomato's still on the vine?
Klee: Yes, they do. Most of the important volatiles are synthesized by the fruit basically after it's started to change color and before it is fully red. And so, basically, if you pick that tomato early when it's still green, you're disrupting the natural ripening process. It occurs, but it doesn't occur quite the same way as when it's attached to the plant.
CNN: People talk about heirloom tomatoes being closer to the "original" tomato. How is the heirloom tomato different from what we consider the modern, commercial American tomato?
Klee: There is no real definition of an heirloom tomato. Most people would classify heirlooms as being very old varieties. I would probably draw the line at maybe World War II. Most people would say heirlooms are what we call open-pollinated -- that is, when you can save the seed. It breeds true.
Virtually all of the modern varieties are hybrids, so that means when you get seeds out of the fruit, they're not going to breed true, they're going to be different. Generally heirloom varieties are really hard to grow. You don't get a lot of fruit, and sometimes the fruits have really short shelf lives. They crack easily and they're really soft. Modern varieties are far, far superior in terms of yield, disease resistance and shelf life. But the big thing -- at the heart of the difference -- is heirlooms frequently do taste very good, and modern varieties frequently don't taste very good.
CNN: I'd argue that the texture is not even that good. On a fast-food hamburger, you get a tomato, and it's just soggy and flavorless and not even a pretty color.
Klee: You're absolutely correct. And part of the texture is also related to the modern breeding for long shelf life and shipability. People are passionate about tomatoes, but a large majority of those people are really disappointed in what they can buy at the supermarket, and so they don't buy them. But if I can make a tomato that really tastes like an heirloom tomato, that's really good, would you really like it more?
And if you really liked it more, would you eat more of it? I think if we're successful in understanding how to improve flavor, to bring back flavor to where it was 100 years ago, but maintain that in a package that the growers can still grow and make money at, you'll make healthier dietary choices. What if we can make a peach that you can bite into that will taste just like a peach is supposed to taste like, like you just picked it off the tree, warm from the sun. Would you choose to eat that instead of a piece of cake? By and large, I think the answer to that is yes.