The little stickers stuck to individual fruits and vegetables may be a slight inconvenience, but they serve a practical function. 

Their purpose dates back to the late 1980s, when the industry needed a way to differentiate organic produce form conventional produce sold unpackaged. Cashiers could not tell a ‘conventional’ banana from a more expensive organic banana and were concerned they might charge the lesser price. 

“They look the same,” said Ed Treacy, VP of supply chain for the U.S.-based International Fresh Produce Association. “The retailers were paying a lot more for organic and selling it at the conventional price. That was the problem we set out to solve, and we did.” 

Under the system created by the Produce Marketing Association (now the International Fresh Produce Association), stickers contain Price Look Up (PLU) codes. Every variety of fruit and vegetables was given a four-digit code between 3000 and 4999. Organic versions were given the same code, but with a 9 prefix. So yellow Cavendish bananas are 4011, and organic Cavendish bananas are 94011. 

Treacy said after two retailers in Illinois and California implemented the stickers, word spread among peers about how much marginsincreased, and within two years their use was almost universal. “They made the retailers more money by charging the right price for organic.” 

The bottom line allure meant grocers adopted PLUs much more quickly than initiatives such as unit pricing, designed to provide consumers with the ability to more easily compare prices of products sold in different quantities. 

Though not part of the original intent, PLUs also made it easier for grocers to implement self-checkout. 

The Canadian Food Inspection Agency does not mandate the use of PLU codes stickers. 

And if consumers accidentally ingest the sticker when they take a big bite out of their newly purchased Royal Gala apple (4173 or 4174), the stickers have to be ‘human safe’ because they are touching food, and the inks are vegetable based. 

“You’re fine,” Treacy said, adding it’s not recommended. “They don’t taste good.”