The “Best Before” label on your food is really just a suggestion, and properly stored food can be edible for days, even years, after the listed date. (Even the Food and Drug Administration says so.) Doug Rauch, the former president of the quirky grocery chain Trader Joe’s, saw this as a business opportunity, and he’s come up with a way to sell yesterday’s food.

Talking to NPR recently Rauch explained the idea behind his Daily Table chain of grocery stores:

It’s the idea about how to bring affordable nutrition to the underserved in our cities. It basically tries to utilize this 40 percent of this food that is wasted. This is, to a large degree, either excess, overstocked, wholesome food that’s thrown out by grocers, etc. … at the end of the day because of the sell-by dates. Or growers that have product that’s nutritionally sound, perfectly good, but cosmetically blemished or not quite up for prime time. bring this food down into a retail environment where it can become affordable nutrition.

Now, the idea of saving old food from the waste bin by repurposing it is not new, at all: 1700 years ago the Romans were mixing stale bread with milk and egg, breathing new life into a meal that we now call French toast. The bones and meat from yesterday’s roast end up in today’s soup; browning bananas beget banana bread. Left over fast food burgers turn into chili.

But the out-of-date and overstocked food that Rauch wants to sell already often has a home. The Atlantic took a look last year at the “second life” of expired food, and a lot of it, they write, goes to food banks: “more than half of the 8,360 supermarkets surveyed donated 100,000 pounds of product that they could not sell to food banks annually.”

There is also already a industry of so-called “salvage” grocery stores, which pick up out-of-date food and sell them at a discount—a system pretty similar to Rauch’s plan. “With the current economic troubles,” says the Atlantic, “expired foods are increasingly becoming a part of America’s diet. Salvage stores are seeing a steady uptick in business from cost-conscious consumers. Similarly, food banks across the country have reported an increase of up to 40 percent in the demand for emergency food assistance in the past year, according to a survey by Feeding America, a network of over 200 food banks.”

So, what it seems Rauch really found was a way to sell people on an old idea, and to pluck a few extra dollars out of the food supply system. But, as NPR notes, food waste is a huge problem–“40 percent of our food gets thrown out.” The environmental movement hasn’t had much luck fixing this problem. Maybe the market and some good PR can.

More from Smithsonian.com:

A Four-Point Plan For Feeding Nine Billion People