When Michael and Jane Stern, the duo behind Roadfood, the website and book series chronicling the best eats in small-town America, gave the Smithsonian Institution access to their storage unit full of old menus, photos and notes accumulated from nearly 50 years on the road, they also gave curators a little more than they bargained for. Letting the Smithsonian rifle through your things also means that curators may air your dirty laundry. Literally.

“They took whole filing cabinets full of things, and I later got a note from the curator saying, ‘You want your medical records? Or your tax records?'” Michael said. “Jane said they found her underwear in one of the boxes. So that was not so interesting to the Smithsonian.”

Jane was amused. The curators “wore white gloves like you wear when you dust the dust off a mummy’s feet at an archaeological dig,” she said. “This is our crappy storage locker. It was funny to see it treated with such dignity.”

The Sterns are being modest. The pair were chronicling diners, drive-ins and dives long before the king of Donkey Sauce was (and, not that it’s a race or anything, but their stuff is now in the Smithsonian, and his is not). From that storage locker, curators were able to preserve artifacts from a disappearing slice of Americana. Some of the papers, photos and menus the Sterns donated are records of rare foods, or historic restaurants that have closed. The 17 cubic feet of archival materials will reside in the American History Museum’s archives and the Smithsonian Libraries.

They were eclectic in a way that reflects their own approach, their own curiosity. It opened a bigger door for me,” said curator Paula Johnson, who is project director for the Smithsonian’s American Food and Wine History Project. “They’re not just about food and the road. They have these major interests in the American West, in Elvis, in American popular culture.”

It was hard for them to part with some of their collection.

“There was that heart-tugging moment when we’d see 8,000 postcards that we collected, and I’d say, ‘Oh my God, we can’t give these away,'” Jane said. “We don’t have children. If we die this stuff is just going to go in a dumpster. This is a great opportunity to keep it together in what is absolutely the greatest place in the world to have it.”

Michael says he hopes that visitors to the Smithsonian will be able to see America’s roadside eateries as a microcosm of American culture.

“I hate the word ‘foodie,’ but there are some foodies for whom the interesting thing is what’s on a plate,” Michael said. “What’s interesting for us is all of the connections that that thing on a plate has to how people live. If you look at the totality of what the Smithsonian has from us, it’s food in the cultural context.”

The Sterns’ collection is not the only recent addition to the Smithsonian’s food-related collection. Chef Rick Bayless, who accepted the Julia Child Award at the museum on Thursday, donated a chef’s coat and apron, dishware from his restaurants, and a typewriter and field notes from his years spent doing research in Mexico.

Who would have asked Rick Bayless for a typewriter? Nobody,” said Johnson, who was part of the team that brought Child’s kitchen to the Smithsonian in 2001. The typewriter artifact emerged after conversations about “his really important field research and asking, ‘Do you have any notes from that? Do you have anything you collected when you were in Mexico?'” Johnson said. “It’s a process of understanding the history of the person, of the industry, of the activity.”

Bayless even donated some oregano and escabeche that he had preserved from his time in Mexico in the 1980s. The museum does not usually collect such hard-to-preserve items, but for Bayless, they made an exception.

We put that in a special category of organic material, so when it does deteriorate we don’t have a big paperwork hurdle,” Johnson said. 

As for the Sterns, they’re still hitting the road after hundreds of thousands of miles, more than a dozen co-written books and their amicable divorce (they remain partners in the business). They’ve been through what they estimate to be more than 50 cars — Michael says they stopped counting years ago, at 38.

“When we started back in the ’70s, we had a hard time convincing a publisher that there were enough interesting restaurants in the United States to fill a guidebook, which today seems utterly preposterous,” Michael said. The biggest lesson they’ve learned from those years? “American cuisine is like the population of this country — spectacularly diverse and always changing,” he said. Also, that “American cuisine has plenty of vulgarity and audacity to it. But that’s what makes it so much fun.” 

Having driven through states red and blue, they’ve seen how food can unite a country that has so often been described as divided.

“The types of restaurants that interest us are exactly the types of restaurants that politicians love to go to to prove they’re normal people,” Michael said. But taste is nonpartisan. “In many ways, when it comes to favorite foods, political preferences really get put aside. I cannot tell you the number of restaurants we’ve been to that have photographs of George Bush and Bill Clinton side by side. Or Barack Obama and Jesus and Dwight Eisenhower, all of whom loved their fried chicken.”