How To Tell If Eggs Are Bad?

What's the float test for eggs?

The float test is the most reliable single way to check egg freshness. Fill a bowl with cold water deep enough to fully cover the egg, then gently drop the egg in. Fresh eggs sink to the bottom and lie flat on their sides; eggs about 2-3 weeks old sink but stand upright at the bottom; eggs that float to the surface are old enough that air has accumulated inside the shell and should be discarded. The science: as eggs age, moisture and gases pass through the porous shell and the air cell inside grows larger, eventually making the egg buoyant. The test works for both raw eggs in the shell and unwashed farm-fresh eggs; commercial washed eggs lose freshness slightly faster because the protective bloom is removed during processing.

How do you tell if an egg is bad by smell?

A bad egg has an unmistakable sulfurous, rotten smell that's immediately obvious when you crack the shell. Fresh eggs have either no smell or a very mild, neutral aroma. The sulfur smell comes from hydrogen sulfide gas produced by bacteria breaking down the egg's proteins. To check, crack the egg into a separate bowl rather than directly into your recipe; this prevents a single bad egg from ruining other ingredients. If you smell anything sulfurous, rotten, or unmistakably off, discard the egg and any food it touched. Pre-cracked eggs that smell off should also be discarded; the smell is the body's clearest warning signal that food has spoiled to the point of being unsafe.

What does a bad egg look like inside?

Cracked open, a bad egg shows several visible warning signs. The egg white may be discolored (pink, green, or iridescent), or unusually thin and watery rather than the slightly cloudy gel of fresh whites. The yolk may be flat and spread out rather than rounded and standing tall; discoloration on the yolk (gray, green, or black spots) signals bacterial contamination. Blood spots and tiny tissue spots (chalazae) are normal and not signs of spoilage; they're harmless and can be removed if preferred. The white shouldn't have unusual textures like sliminess or stringiness beyond the natural chalazae. Fresh eggs have firm whites that hold their shape; old eggs spread thinly across the bowl when cracked.

Can you eat eggs past the printed date?

Usually yes. The printed 'sell by' or 'best by' date on egg cartons is conservative; properly refrigerated eggs typically remain fresh and safe for 3-5 weeks past the printed date. The USDA's official guidance is that eggs are safe to eat 3-5 weeks past the sell-by date when continuously refrigerated below 40 degrees F. The 'use by' date is slightly less conservative but still has buffer. Always verify freshness with the float test or visual inspection rather than relying on the printed date alone, since storage conditions matter more than time. Eggs that have been left at room temperature for more than 2 hours should be discarded regardless of date because warming and re-refrigeration accelerates bacterial growth.

How long do raw eggs stay fresh?

Raw eggs in the shell last 4-5 weeks past the pack date when continuously refrigerated below 40 degrees F. Store eggs in the original carton on a refrigerator shelf, not the door, where temperature fluctuates with each opening. The carton protects eggs from absorbing odors from other foods, since eggshells are porous. Raw eggs out of the shell (separated yolks and whites) last only 2-4 days in the fridge in airtight containers; raw whites freeze well for up to 12 months, while raw yolks need a pinch of salt or sugar before freezing to prevent gelling. Unwashed farm-fresh eggs can last 1-3 months at room temperature thanks to the natural protective bloom on the shell, though refrigeration extends life dramatically.

Are cracked eggs safe to use?

Cracked eggs from the carton should be discarded if you discover them after purchase. The cracks allow bacteria like Salmonella to enter the previously sealed interior, and the cold temperatures don't kill bacteria that have already gotten inside. If you crack an egg yourself just before cooking (and it goes into a pan within minutes), normal cracking isn't dangerous. The risk is from cracks that happened hours or days before use, where bacteria have had time to multiply. Some recipes specifically call for slightly cracked eggs (for poaching), but these should be used immediately. Inspect each egg from the carton before cracking; if you see cracks, hairline fractures, or wet spots in the carton, discard those eggs without using them.

What are the signs of Salmonella in eggs?

Salmonella contamination doesn't produce visible signs in eggs, which is the main reason food safety experts emphasize cooking eggs thoroughly. The bacteria can be present inside the egg from the hen or on the shell exterior; you can't tell by sight, smell, or appearance whether an egg is contaminated. Pasteurized eggs (heat-treated in the shell before sale) have essentially zero Salmonella risk. Standard commercial eggs have a low contamination rate (about 1 in 20,000 eggs in the US), but the risk increases with raw or undercooked egg consumption. Children, pregnant women, elderly people, and immunocompromised individuals should avoid raw or runny eggs entirely. Symptoms of Salmonella food poisoning (diarrhea, fever, stomach cramps) appear 6-48 hours after eating contaminated food.

When should you discard eggs?

Discard eggs immediately if they float in water (clear sign of spoilage), smell sulfurous or rotten when cracked, show discoloration in the white or yolk, have unusual textures (slimy, stringy, watery), have visible cracks before you crack them yourself, or have been left at room temperature for more than 2 hours. Eggs that taste off when sampled (in cookie dough, scrambled, or other tests) should be discarded along with anything they touched. When in doubt, throw them out; eggs are inexpensive enough that the food poisoning risk isn't worth keeping questionable ones. Trust multiple tests together rather than any single test, since spoilage can sometimes present subtly. The float test plus a visual check is the most practical home assessment.