What The Julian Date Says About A Carton Of Eggs

While food labeling can be a massive headache to decipher these days, there's a method to the madness and they're something we should be thankful for. Believe it or not, with the exception of baby formula, expiration dates on food items are not required by federal law, according to the USDA. With that in mind, the hodge-podge of letters and numbers you find stamped on the short side of an egg carton is not just a lesson in some new form of hieroglyphics. 

These numbers tell us a lot about the eggs lined up like soldiers inside, such as when they should be sold and when we should consume them or whether they're regulated by the government or not. While a popular male name, the Julian in "Julian date" refers to the use of the Julian calendar, per Little Things, which is just the assigning of 365 days to a year. How does this apply to eggs and those three numbers stamped on the side of the carton?

A packaging date by another name

The Julian date is the day the eggs were washed, graded, and packed in the carton, per Egg Safety Center. The year starts with 001 on the first of January and ends on New Year's Eve with 365. The Incredible Egg suggests the eggs can stay in their carton in the refrigerator for up to five weeks after the listed Julian date. It's important to know the date the eggs are washed. Washing removes the bloom, which is a protective layer the hen imparts on the shell during birth. Once this bloom is gone, eggs require a spot in the fridge to remain bacteria-free and safe (via MasterClass).

The other numbers on the carton can also be a bit perplexing. You'll often also see a "sell-by" date as well as the letter "P" followed by a sequence of digits. The "P" followed by numbers is simply the number of the processing plant where the eggs were packaged on their Julian date. And while the sell-by date isn't regulated by the government, a state's laws may come into play depending on where in America the marketing is being done. For this reason, if you see a "sell-by" or "expiration" date hanging out near the Julian date, it's worth taking note of and purchasing the eggs prior to that date.