How do food manufacturers pick ‘best by’ dates?


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Manufacturers have a few ways to figure out how long their food will be safe

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No one wants to serve spoiled food to their families. Conversely, consumers don’t want to throw food away unnecessarily – but we certainly do. The United States Department of Agriculture estimates Americans toss out the equivalent of US$162 billion in food (PDF) every year, at the retail and consumer levels. Plenty of that food is discarded while still safe to eat.

Part of these losses are due to consumers being confused about the “use-by” and “best before” dates on food packaging. Most U.S. consumers report checking the date before purchasing or consuming a product, even though we don’t seem to have a very good sense of what the dates are telling us. “Sell by,” “best if used by,” “use by” – they all mean different things. Contrary to popular impression, the current system of food product dating isn’t really designed to help us figure out when something from the fridge has passed the line from edible to inedible.

For now, food companies are not required to use a uniform system to determine which type of date to list on their food product, how to determine the date to list or even if they need to list a date on their product at all. The Food Date Labeling Act of 2016, now before Congress, aims to improve the situation by clearly distinguishing between foods that may be past their peak but still ok to eat and foods that are unsafe to consume.

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Aside from the labeling issues, how are these dates even generated? Food producers, particularly small-scale companies just entering the food business, often have a difficult time knowing what dates to put on their items. But manufacturers have a few ways – both art and science – to figure out how long their foods will be safe to eat.

Consumer confusion

One study estimated 20 percent of food wasted in U.K. households is due to misinterpretation of date labels. Extending the same estimate to the U.S., the average household of four is losing $275-455 per year on needlessly trashed food (PDF).