Cracking The Code

If you thought those little stickers on produce were merely there to speed the checkout process for the bored cashier at your local grocery store, you’ll be shocked to know that those annoyingly adhesive (more on that in a minute) stickers actually contain a wealth of information about the produce you’re about to purchase.

Known in the industry as a PLU code, or price lookup number, the digits were developed by the Produce Electronic Identification Board, an offshoot of the Produce Marketing Association. Since introducing the PLU codes in supermarkets in 1990, this produce industry trade-group has tagged more than 1,200 produce items with their labels. In fact, this coding system, which was first introduced in the good ol’ US of A is currently used in Austria, New Zealand and several countries in Europe and applies not only to produce, but also to nuts, dried fruit, herbs and flavorings. Not bad, ey?

So how do you decipher a PLU code?

The first step is to count the number of digits included in the sticker.

– A four-digit number applies only to conventionally grown produce, that is, those that were grown with chemical assistance.

– A five-digit code that has the first digit 9 pertains to organically grown produce.

– A five-digit code kicking off with the number 8 applies only to genetically engineered items, such as seedless grapes. For those of you who steer clear of GMO this is one to remember.

Beyond that, the remaining numbers, known as “retailer assigned codes,” are less informative and are typically assigned by retailers either on a local, regional or national level.

The one exception to this rule, according to some Web sites dedicated to deciphering the PLU codes, is that the codes can sometimes be used to figure out a products size. For example, a small, conventionally grown yellow onion purchased in the U.S. will bear the code 4665, while a large yellow onion will bear the code 4093. However, the numbers are assigned quite randomly and…well, if you need a number key to tell you whether you are purchasing a large or small onion in your hand, perhaps you have bigger problems!

While we’re on the topic, the folks behind the PLU codes want you to know that the adhesive used to attach the stickers is considered food-grade, but remind you that the stickers themselves aren’t edible. To that end, the group is currently considering several new methods of labeling produce, including etching using lasers (fancy!) and printing or tattooing using ink made from natural substances such as blueberry juice.

Because that’s just what we need, a vegetable with a tattoo!

To learn more about PLU codes, visit You’ll be asked to fill out four quick questions, but they don’t pertain to anything personal and appear to be more for Web site tracking purposes. If you’re still thirsty for more info on the process behind assigning the codes (or would even like to submit your own!), check this (PDF) out.

cdozo Flickr Photo (CC)

Further Reading:

Genetically Modified Foods: Super Solution or Franken Future?

Safe Cooking Temperatures

How to Shop a Farmers’ Market

How to Eat Enough Omegas

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