I’ll never forget the results of the derecho that hit the Midwest a few summers ago. With the winds came power outages that drew neighbors out into their yards (time to grill that stuff from the freezer!) and grocery store folks into depression. Cartloads upon cartloads of artisan cheese, meat, and dairy products were piled into the trash, and if anyone in the area had electricity to store or cook the foods, it would have made for the finest dumpster diving in the land.
The frozen and refrigerated cases were empty for nearly a week as we waited for the electricity to return. A few items, though — like bags of sauerkraut and cartons of eggs — stayed curiously in their places within the room-temperature case. It was at that point that I started to think about food waste, and expiration dates.
Here's the deal. The "best by" dates on consumer packaged goods are determined by the producers, and not by the United States government. R&D teams painstakingly research when a food's quality diminishes, but there's no across-the-board scientific standard — at all. A high-end macaron maker may decide that 48 hours is the longest their product can sit in a refrigerated case, while a similar producer (with a lesser idea of perfection) may say that twice that time is totally okay. The only category of food mandated to have dates on its packages by the FDA is baby formula.
For all others, it's mainly for the convenience of the industry. With a supply chain that sometimes takes three or four months to get an item from a producer to the grocery store shelf, retailers and distributors require dates to make certain that items that pass through their hands are younger than older.
The best way to know whether something is safe to eat is to use sight and smell, and then taste. (I've forgotten many a sample of kale chips snagged at a trade show in the back of my cupboard that are totally safe to eat, but have no flavor.)
That said, below is what the FDA says about dates. (And when it comes to those eggs? Three to five weeks is a safe bet.)
Types of Dates
- A "sell by" date tells the store how long to display the product for sale. You should buy the product before the date expires.
- A "best if used by (or before)" date is recommended for best flavor or quality. It is not a purchase or safety date.
- A "use by" date is the last date recommended for the use of the product while at peak quality. The date has been determined by the manufacturer of the product.
- "Closed or coded" dates are packing numbers for use by the manufacturer.