Author Michael Ruhlman says U.S. grocery stores represent extraordinary luxury that most Americans don’t even think about.

Grocery stores in America have changed from neighborhood corner markets to multimillion-dollar chains that sell convenience — along with thousands of products — to satisfy the demand of the country’s hungry consumers. What caused this transformation? And what will our grocery stores be like in the future?

Award-winning food writer Michael Ruhlman, author of more than 20 books — including the best-seller The Soul of the Chef and co-author of The French Laundry Cookbook with chef Thomas Keller — examines this phenomenon through the story of the Midwestern grocery chain Heinen’s. His new book, Grocery: The Buying and Selling of Food in America, not only offers insights on how we produce, distribute and buy food, but seeks ways of understanding our changing relationship with what we eat and how we get it.

To talk about some of these issues, Ruhlman met with NPR’s Ari Shapiro of All Things Considered at a Harris Teeter grocery store in Washington, D.C.

ARI SHAPIRO: Welcome to the Harris Teeter grocery store in Washington, D.C. We’re going to dig into the store and wander around its various sections. But just standing here at the entrance, you can see a bit of produce, a bit of prepared food, a magazine rack, charcoal. Is there something you didn’t know before you started researching the book that you now see in a different way?

MICHAEL RUHLMAN: The sheer quantity of stuff that we buy and that’s available to us. It represents the extraordinary luxury that Americans have at our fingertips, seven days a week.

We are in the first section that most people usually walk into in a grocery store: produce. It was so interesting to read about the time that you spent with the produce buyers behind Heinen’s — the chain in Cleveland — and the debates they had about whether the cantaloupes were sweet enough, whether there were…