Countless kitchen squabbles go something like this: Someone looks at the date on the lettuce and thinks it has gone bad. The other person says it is perfectly fine. So who is right?
In the U.S., about 30% to 40% of all food is wasted, or about $161 billion worth of food, according to Agriculture Department estimates. While it is unclear how much of that is due to consumers misreading date labels, a recent survey of over 1,000 grocery shoppers by the Food Marketing Institute, a trade association for grocery stores, showed that nearly half of consumers said they threw out food either “fairly often” or “every time” after the sell-by or best-by date.
Yet, terms such as sell-by, use-by and best-before don’t indicate the safety of food, as many people believe. The dates are typically set by the manufacturer to indicate when food is at its peak quality. Still, many consumers believe that not sticking to those dates could make them sick. Most products are still safe to eat after the dates listed on the packaging.
There is little federal regulation. Some states regulate date labeling on certain foods, such as milk or eggs. In other cases, consumers rely on manufacturer-provided date codes. And sometimes, it is anybody’s guess.
“My observation is that even people who ignore the dates think they’re breaking a rule,” says Dana Gunders, a Natural Resources Defense Council scientist focused on food and agriculture. “The manufacturer is not trying to tell you to throw a product out at that date.”
Throwing away food can make people feel guilty, and much of the reason why is rooted in the way we grew up. Some households are likelier to toss food while others are more economical.
For Des Moines, Iowa, couple Adam Lackey and Victoria Brenton, whether food in the fridge is still good is a constant source of disagreement. “It’s a debate every day,” says Ms. Brenton, a manager at the state health department. (Her work isn't related to food safety issues).
Mr. Lackey barely considers dates stamped on food. “I’m more of a smell test, taste test kind of person,” he says. Ms. Brenton, however, regularly cleans out the fridge, tossing lingering leftovers and cartons of milk past the sell-by date. “I’m concerned about food-borne illnesses,” she says. “I’m paranoid.”
Further confusing consumers, the food-dating language varies by which audience it is intended for. The sell-by date is primarily meant for retailers to control stock. A best-by or use-by date is the manufacturer’s recommendation of the last day when a product can be eaten at peak quality. A freeze-by date indicates that a food’s quality can be stretched longer when freezing by that date.
At the National Food Lab in Livermore, Calif., 45 trained “sensory” panelists test foods for manufacturers by rating and describing the “aroma, flavor, texture and mouth feel” over time and at different temperatures, says Jena Roberts, vice president of business development for the company, which performs shelf-life studies for food manufacturers. After one or two years of testing, the results turn into a recommendation of what is peak quality, when it occurs, and what the shelf life should be, Ms. Roberts says.
Such testing helped the California Walnut Board, which represents walnut processors, prove that storing walnuts in the refrigerator kept them fresher longer than at room temperature. In a study begun in March 2013, walnuts only lasted 8 months when stored at 70 degrees Fahrenheit or warmer before they started to get a “rancid, turpentine smell,” says Carl Eidsath, technical support director. But the 66-week study showed that refrigerated walnuts still tasted fresh after a year. Almonds can last for two years if stored in similar cool and dry conditions, according to the Almond Board of California.
The main reason food products can make people sick with food poisoning isn’t their age, but whether a bacterial contaminant—like certain types of listeria or salmonella—has entered the food. Someone might find the scent or taste of old food gross, but that is different from causing food-borne illness.
Food under certain conditions may be more susceptible to contamination or bacterial growth. If food has been poorly refrigerated (over 40 degrees Fahrenheit) or if there was a hole in the packaging, certain bacteria could come into contact, seep in and multiply over time.
Food consultants say that people throw out more food when safety concerns are heightened.
“In the context of food safety recalls, people are more afraid of their food than they probably have been in previous generations,” says Kara Nielsen, culinary director at Sterling-Rice Group, a Boulder, Colo., consulting firm.
In Cambridge, Mass., Mahalia Cole recently noticed expired food containers in boyfriend David E. White Jr.’s pantry and refrigerator, including opened cocktail sauce and strawberry jam. “I took out things that were a year expired,” says the 30-year old attorney, and left them on the kitchen table. It was intended as a subtle hint. “He could decide,” she says.