Scientists wish to understand why freshness standards adopted by people smack of 'double standards'.Why do people refuse to pick up a carton of "expired" milk from a store but not hesitate to use the same milk into a cup of coffee at breakfast ?
The new study has detailed the reasons behind why consumers tend to consume products that are past their expiration dates if they are in their refrigerators than if they are in a store.
For the study, the 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," wrote the authors.
There are many possible reasons consumers may want to consume "expired" food in their refrigerators, one of which is "getting their money's worth."
However, 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," explained the authors.
In three studies, the researchers compared whether people wanted to consume yogurt smoothies that were past or not past their freshness dates.
According to the authors, "ownership" of the smoothie shifted the default hypothesis from "shouldn't consume because expired" to "okay to consume."