We're not shy about our affinity for the Cherokee Purple, a purplish package of sweet, acid and savory tomato greatness.

But every year, the Cherokee Purple's preeminence (in our mind, anyway) is challenged by new heirlooms we've never tried before. This year, we're wowed by the Paul Robeson, a varietal from Russia which, in addition to its gorgeous dark red tones and earthy taste, is named for a famous African-American singer, actor and civil rights activist.

It's these stories of people, places and soils of yore that are a huge part of heirlooms' appeal, according to Jennifer Jordan, professor of sociology at the University of Wisconsin, Milwaukee. And by cultivating and consuming this biodiversity, we're literally keeping the past alive.

Jordan's book, published earlier this year, is called Edible Memory: The Lure of Heirloom Tomatoes and Other Forgotten Foods. It explores the powerful social force of nostalgic foods, and why a "growing number of people seek in heirlooms both a new culinary experience and a connection to a more generalized past."

One big reason? The widespread modernization and industrialization of farming in the U.S. As it's made produce cheaper, more uniform and in some cases, less flavorful, "authentic" and "heritage" foods offer consumers an alternative. The predominance of the industrial model of farming is also motivating seed savers to become stewards of, and highlight the value of, the genetic diversity embedded in heirloom seeds.

We caught up with Jordan by phone to chat about the heirloom food movement. Here's part of our conversation, edited for brevity and clarity.

Why do we have this tendency to infuse foods with the past?

I think there are several different reasons. Food can be very personal, for example, edible memories within families. Here in Wisconsin, rhubarb patches are really important. If a house gets sold, people vie to get cuttings of the plant. If rhubarb is something you grow up with, you may want to carry it into the future — it's a very immediate memory.

At the other end of the spectrum, a lot of people are interested in experiencing the past at places like colonial Williamsburg, where you get immersed in a sensory experience. Food is another way to do that. I got the idea for the book by thinking about how the heirloom tomato and the antique apple allow you to eat a piece of history.

When did the heirloom food movement get started?

Heirlooms started to get public awareness in the U.S. in the late 1980s and '90s. Before then, it was becoming a concept among home gardeners. In 1984, The Heirloom Gardener was published. And then it really takes off in the '90s.

Where do you see it now?

There are clearly a lot of people, in a lot of different places, who love heirloom tomatoes, and grow them or buy them from a farmer. They make them a big part of their lives a particular time of year — like right now.

Access to the seeds and seedlings has really increased. That's an interesting change. Home gardeners have a lot more opportunities to bring heirloom seeds into their gardens.

But there are still people who have't heard of them. And now we're seeing food writers talk about the heirloom tomato in a weary tone: If it's on the menu, then the menu is behind the times.

You describe how "much vegetable life has moved in and out of fashion," and that while the heirloom tomato and apple are celebrated today, many heirloom vegetables continue to languish in obscurity. What's an example of a vegetable that was once fashionable but hasn't garnered much treatment as an heirloom today?

Artichokes were eaten by European kings and queens, and signified wealth and taste. But when the artichoke came to America from the Mediterranean, it marked you as foreign if you grew it or ate it. It's never had widespread popularity in the U.S. and is still so regional — it grows mostly only on the central coast of California. I grew up there, and for me it was one of the most familiar vegetables, so it's part of my edible memory. But today a lot of Midwesterners have never had an artichoke and they're not bothered by that.

Many of us are discovering "new" heirlooms or "exotic" fruits and vegetables, but it's often relative to our experience, isn't it?

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