Why is it acceptable for someone who would never
purchase "expired" milk at the store to pour "expired"
milk into a cup of coffee at breakfast? A new study in the Journal
of Consumer Research explores the reasons consumers are more
likely to consume products that are past their expiration dates
if they are in their refrigerators than if they are in a store.
Authors Sankar Sen and Lauren G. Block (both Baruch College/CUNY)
explored a phenomenon termed the "endowment effect,"
meaning that owning a product increases a consumer's valuation
of it. The endowment effect has been studied before, but not
in regard to perishable products.
"Few people would knowingly purchase products past their
freshness dates; in fact, shoppers often leave supermarket shelves
in disarray after combing the display for, say, the carton of
milk stamped with the freshness date furthest away," the
authors write. While there are many possible reasons consumers
may want to consume "expired" food in their refrigerators,
including "getting their money's worth," the authors
found that even when they controlled for costs and motivations,
consumers were still more likely to eat or drink expired products
that were already in their possession.
"In this research, we show that merely owning a product
past its freshness date provides enough reason for people to
be willing to consume such expired products...Importantly, this
increase in a person's willingness to consume an expired product
is accompanied by lower estimates of the perceived risk of getting
sick from consuming it," the authors explain.
In three studies, the researchers compared whether people wanted
to consume yogurt smoothies that were past or not past their
freshness dates. The authors believe that "ownership"
of the smoothie shifted the default hypothesis from "shouldn't
consume because expired" to "okay to consume."
"If you caught a glimpse of moldy cheese being served
at a function you were attending, you wouldn't eat it, thinking
it likely that you could get sick from old cheese," write
the authors. "However, if that same moldy cheese is in
your refrigerator, hey, what's a little mold?"
