Skip to content
Subscriber Only

These Women Taste Rancid Foods So You Don’t Have To

Sensory panelists taste testing at The National Food Lab
Sensory panelists taste testing at The National Food LabCourtesy The National Food Laboratory, LLC

If you bite into a granola bar and it has a disgusting, kind of fishy flavor, it’s probably because the oil in the nuts has oxidized. This is the kind of thing Dawn Chapman knows. A sensory and consumer scientist at the National Food Lab, she runs a team of 40 part-time testers who taste packaged foods—over and over again—to determine how long they stay tasty. “Anything in the grocery store, we’ve likely tested it,” she says.

The goal is to identify how much time can pass before a food no longer tastes good, which in turn dictates the sell-by date. Generally, foods are still safe to eat after that point, but they won’t taste as they were intended. Hiring people to eat food repeatedly until it’s certifiably icky can costs anywhere from $8,000 for a simple test to $100,000 for a more complicated, long-term evaluation. For the manufacturers of shelf-stable foods, the goal is the longest possible shelf life, while also making sure consumers don’t eat their products when they’ve passed peak quality.