AUDIE CORNISH, HOST:
It's ALL THINGS CONSIDERED from NPR News. I'm Audie Cornish.
MELISSA BLOCK, HOST:
And I'm Melissa Block. Every year, American grocery stores discard 10 to 15 billion dollars in unsold products. The items might be damaged, discontinued, seasonal or just close to their sell-by date. Some is sent to food banks, some to landfills, but as NPR's Serri Graslie reports, increasingly, the food is resold to the public.
SERRI GRASLIE, BYLINE: Across the country, more Americans are doing their grocery shopping in between antique dressers and old farm equipment.
(SOUNDBITE OF AUCTIONEER)
GRASLIE: Grocery auctions have been growing in popularity since the recession as a way to get a lot of food for not a lot of money.
UNIDENTIFIED MAN: Ten pounds of chicken. (Unintelligible).
GRASLIE: On this Saturday afternoon, around 80 people have filled the folding chairs at the Chesapeake Auction House in St. Leonard, Maryland.
UNIDENTIFIED MAN: Sold (unintelligible) $11, 229. Eleven dollars. (Unintelligible) next, five pounds of (unintelligible).
GRASLIE: They've all come for great deals like that. Frozen chicken for just over a dollar per pound. Dave Ring of Maryland is a veteran of the grocery auction.
DAVE RING: We've been coming to the food auctions for who knows how long now, get what we want. Sometimes we get too much.
GRASLIE: Ring and other attendees have brought huge coolers, insulated bags and boxes to bring home their haul. Some are buying for big families and even home ec classrooms. These auctions are organized by people who make their living buying up food and other products from stores and warehouses that are trying to unload it, but the exact details of where it comes from is sort of a trade secret.
It's not illegal to sell most expired food, but many Americans are pretty attached to sell and best by dates.
JONATHAN BLOOM: I think we've lost some of our food knowledge and we're not sure when something is good or not.
GRASLIE: That's Jonathan Bloom, author of a book on food waste called "American Wasteland." He says the USDA encourages manufacturers to put expiration dates on meat and dairy products, but that's only to indicate quality, not safety. Somewhere along the line, they became a strict cutoff point for some consumers.
BLOOM: So simply following those expirations dates is something that many Americans just do because it's clear to them and it's easy.
GRASLIE: Bloom says there are consequences to that kind of thinking. In the store, it means food gets pulled off the shelf well before that date. A grocery store doesn't want you to be horrified when you buy nearly expired crackers. They want you to keep coming back.
BLOOM: They know that if they can get people to buy their food for the course of their shopping life, that's infinitely more valuable than one package of food.
GRASLIE: Grocery manufacturers like expiration dates for the same reason. A few years ago, some of them changed their coding system to make expiration dates clear and up front. Dale Rogers is a professor at Rutgers University who studies supply chains. He says, when manufacturers made that change, they ended up shortening the shelf life of some foods for marketing reasons.
DALE ROGERS: Vinegar had seven years of shelf life because what does vinegar turn into? It turns into vinegar.
GRASLIE: To make it appear fresher, he says they cut its shelf life down to a single year.
ROGERS: They don't believe that consumers really want to buy a product that, you know, is five or six years old. Before the open code dating, there's a likelihood that probably consumers did buy vinegar that was more than a year old.
(SOUNDBITE OF AUCTIONEER)
GRASLIE: Dave Ring, the grocery auction veteran, says he doesn't put too much stock in sell by dates. In fact, he had no hesitation before diving into some yogurt he just bought at the auction.
RING: I can tell you - we've been coming, like I said, a long time. I've never gotten anything bad.
GRASLIE: There might be minor changes in the taste, texture or appearance of expired foods, but eating yogurt that expired at midnight probably won't hurt you. Dave Ring didn't even know how old his was.
RING: I have no idea. I didn't ask. Don't really care. It's good.
GRASLIE: It was a good deal, too, just $2.50. That's for a case of 12. For NPR News, I'm Serri Graslie.