The dates found on egg cartons, such as “Best By,” “Sell By,” or “Use By,” are generally indicators of peak quality and not strict safety deadlines. These terms suggest when the eggs are expected to have the best flavor and texture, which naturally decline over time.
The “Sell By” date primarily serves to guide the retailer on stock rotation. A more accurate measure of the egg’s age is often the “Pack Date,” sometimes printed as a three-digit Julian date representing the day the eggs were placed in the carton. Properly handled eggs are safe to consume well past the suggested time frame because these printed dates relate mainly to quality.
Maximum Safe Shelf Life Past the Date
When eggs are stored correctly under consistent refrigeration, they maintain their safety beyond the printed date. The recommended safe shelf life for raw, in-shell eggs is typically three to five weeks from the date they are placed in the refrigerator. This period extends past the “Sell By” date, which is often set no more than 30 days after the pack date.
The primary concern with older eggs is the gradual decline in internal quality, such as the egg white thinning and the yolk flattening. Safety remains intact due to the protective shell and internal membranes, provided the egg is kept continuously cold. Proper refrigeration is the most important factor, as it significantly slows the growth of potential bacteria, like Salmonella.
Essential Storage Practices
Eggs must be refrigerated at a temperature of 40°F or below to inhibit bacterial growth effectively. Any deviation above this temperature range can accelerate the deterioration process, shortening the usable life.
It is best to keep the eggs in their original carton and store them in the main body of the refrigerator, rather than the door. The refrigerator door is subject to frequent temperature fluctuations every time it is opened, which can compromise the cold chain necessary for preservation. The cardboard carton shields the eggs from absorbing strong odors and flavors from other foods through the porous shell and minimizes moisture loss.
Simple Tests for Determining Freshness
Since the dates on the carton are not absolute safety guarantees, simple at-home tests can confirm the condition of older eggs before they are used. The float test is a reliable indicator of an egg’s age, involving gently placing the egg in a bowl of cold water. An extremely fresh egg will sink to the bottom and lie flat on its side because it contains very little air.
As an egg ages, its porous shell allows moisture to evaporate, and air replaces the lost volume, causing the internal air cell to enlarge. If the egg sinks but stands upright, it is older but still safe for consumption. An egg that floats freely on the surface should be discarded. The ultimate determinant of safety is the smell test: if an egg, when cracked, emits a distinct, pungent, sulfuric odor, it is spoiled and must be thrown out immediately.