Sell-By or Use-By Dates Too Confusing

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During my usual Monday volunteering at the local Red Cross, I was involved in a conversation about the dates printed on the food and drinks we keep in order to feed the victims of local disasters (water, GatorAide, snack bars, and the like). It turns out that many had been confused by what the dates on the packages meant. Some thought they were the “Sell by” date, some the “Best if used by” date, and some the “Use by” date—all of which have different meanings according to which government document or food producer you ask. Apparently, our supplier (SYSCO) has decided to mark all of its packaging with the expiration date, but has also decided to not mark that the date is the expiration date. The simple addition of the ISO “use-by” symbol (an almost empty hourglass) to the date would clear up this confusion.

And therein lies the problem. There is no clear, consistent definition of these terms, so the fact that most consumers have the wrong understanding of them is quite unsurprising. The most important thing to realize, is that none of these imply food past that date is unsafe. Even the “Use by” date is simply when the manufacturer expects the food to no longer have the flavor or quality they expect. An egg used after that date is unlikely to whip as well or have as firm a white when fried, but does not magically become unsafe to eat.

In my opinion, a major contributor to this confusion is the failure to include multiple dates on packages, and make sure that all food producers are using the same definition of the dates. And it might not surprise you that I think symbols would help, too!

In order to be consistent across state and country boundaries, every effort should be made to ensure the harmonization of the meaning and presentation of these dates. There are several standards bodies and specifications that should be mashed-up.

The most constraining standard is that of barcodes. The GS1 organization defines the implementation of 1D and 2D barcodes when used on retail goods, and two of its most recent standards, “GS1 DataBar” and “GS1 DataMatrix” are both capable of encoding product dates along with UPC (a.k.a. EAN/GTID) numbers. Any dates placed on the package should be capable of being expressed in these standards.

Another standard to be integrated is the ISO symbol library, which includes symbols for “date of manufacture” (ISO 7000-2497) and “use-by date” (ISO 7000-2607), but not symbols for “Best Before”, “Production Date”, “Sell-By Date”, or “Packaging Date”.

All these need to be coordinated with the definitions of the terms. The U.S. The National Conference on Weights and Measures (through NIST) publishes the “Uniform Open Dating Regulation”, which is meant as a nationwide guideline for some of these terms. It defines “Sell-By” and “Best if used by”.

There are some arguments against continued use of the “Sell-by” date, since this is really only of interest to stores for stocking purposes. But eliminating this would force stores to use the “Best before” (optimum quality or flavor) date, which previous research has found to be ambiguous for stock rotation purposes (Open Dating of Foods, page 41). So we really need “Sell-by”, “Best-Before” (still acceptable quality), and “Use-by/Expiration” (degraded safety or nutrition) dates to appear on food.

And the distinction and consistent definition of these two latter terms is the most important aspect to improved open dating, in my opinion. The combination of these two dates will help to indicate to consumers that there isn’t a hard cut-off date, but rather, a period of degradation. This will aid consumers in deciding when a product should be discarded or is still safe to eat, without creating a fear that results in an inordinate amount of non-spoiled food being discarded, to the detriment of our landfills and pocketbooks alike.

More to come on this topic soon.

Author: Peter Sheerin

Peter Sheerin is best known for the decade he spent as the Technical Editor of CADENCE magazine, where he was the acknowledged expert in Computer-Aided Design hardware and software. He has a long-standing passion for improving usability of software, hardware, and everyday objects that is always interwoven in his articles. Peter is available for freelance technical writing and product reviews, and is exploring career opportunities in interaction design. His pet personal project is exploring the best ways to harmonize visual, tactile, and audible symbols for improving the effectiveness of alerting systems.

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