Expiration dates on food products are usually a good indication of when one should stop eating or using a food or product.
But many edible items have other numbers on packaging that aren't clearly defined.
One such extra value is found on egg cartons.
Check this number on your egg carton
In the same area as the "best by" date, there's another number. That number indicates what day of the year the eggs were cartoned.
The number, called the Julian date, reveals the day of the year the eggs were packaged. The number on the label is between 1 and 365. If the number is 001, those eggs were packaged on Jan. 1; if the number is 365, the eggs were packaged on Dec. 31.
Consumers might find interest in figuring out how many days have passed since the eggs have been cartoned and how many days total an egg can sit before going bad. But don't forget: An egg could have been laid up to 30 days prior to being cartoned, according to Fresh Eggs Daily.
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