Crack open your refrigerator and you'll likely find a carton of eggs. Some might be fresh, while others have been sitting around for who knows how long past that stamp saying "Best by" or "Sell by."
So how can you tell if those eggs are still good enough to scramble or if they're destined for the trash? With a few simple tests and tricks, you'll be able to determine whether your eggs are still fresh and safe to eat.
In this post, we'll cover everything you need to know about egg freshness, from expiration dates to float tests. Read on to become an expert on determining if your eggs are expired or not!
Performing a Float Test
One of the easiest ways to check an egg's freshness is to see if it sinks or floats in water. Here's how to do the egg float test:
- Fill a bowl with cold water. The water should be deep enough to fully submerge an egg.
- Carefully place the egg in the bowl of water. An egg that immediately sinks to the bottom and lies flat on its side is very fresh.
- If the egg stands on its end or floats, it's older and the air cell inside has expanded. Floating eggs should be discarded.
The float test works because eggshells are semipermeable. As an egg ages, moisture and carbon dioxide escape through the shell, making the air cell inside larger and more buoyant. Fresh eggs have smaller air pockets and are dense enough to sink.
So if your egg promptly sinks to the bottom and lies horizontally, you can safely consume it. But floating or standing eggs should not be eaten.
Checking an Egg's Appearance
Cracking open an egg and inspecting its interior can also reveal signs of freshness. Here's what to look for:
The Shell
A egg's shell should be clean and free of cracks. Dirty shells may indicate unsanitary conditions and cracks make eggs prone to contamination. Discard any eggs with large cracks or damage.
Minor thin "hairline" cracks at the wider end of the egg are usually still safe. These naturally occur as the egg ages and the membrane inside separates from the shell.
The White
A fresh egg white should be thick, clear, and cohesive. As an egg ages, the white thins out and becomes more watery. Older whites are looser and spread out more across the plate.
Cloudy egg whites or discoloration can mean bacterial growth. But some cloudiness is normal for very fresh eggs as carbon dioxide escapes.
The Yolk
Egg yolks should have a round, upright shape and vibrant orange-yellow color. Flat or broken yolks indicate age.
As time passes, water evaporates from the yolk, making it flatter. Runny, diffused yolk edges also signal older eggs.
So look for thick, cohesive whites and plump, centered yolks when cracking open eggs. Older eggs will have thinner, more watery whites and flatter, broken yolks.
Giving Eggs a Sniff
Your nose knows when eggs have gone bad! Here's what you need to know about the smell test:
Fresh Eggs
Crack open a fresh egg and it should have little to no odor. You may notice a faint "eggy" smell but it should not be unpleasant or strong.
As eggs age over time, odor increases due to evaporation through the shell. But a noticeable rotten stench means an egg is no longer safe to eat.
Rotten Eggs
If you crack an egg and detect a potent sulfur or rotten smell, discard it immediately. This means bacteria have multiplied to dangerous levels.
Some describe the noxious odor of rotten eggs as similar to sulfur, ammonia, or vinegar. Either way, that overpowering stench screams "Do not eat me!"
Trust your nose - rancid egg smell is a definite red flag for spoilage and potential food poisoning. When in doubt, throw it out.
Understanding Egg Expiration Dates
Egg cartons are marked with sell by or best by dates. But what do those expiration stamps really mean?
Sell-By Date
This date tells retailers when to remove eggs from shelves. Sell-by dates are generally 30 days from the packing date.
Eggs can still be consumed several weeks past the sell-by date as long as they've been refrigerated. But quality starts declining with age.
Best-By or Use-By Date
This is an estimate of when eggs will be at peak quality and flavor. You can still eat eggs safely several days to weeks beyond this date.
As eggs get older, they may become runnier and better suited for baking versus frying or poaching. Best-by dates range from 30-45 days from packing.
The key takeaway? These labels indicate freshness, not safety. Use expiration dates as a guide along with other tests to determine if eggs are OK to eat.
Decoding the Julian Date
Look closely at your egg carton and you may see a three digit code. This is the Julian date, also called the pack date.
What is a Julian Date?
The Julian date indicates when an egg was washed, graded and packed. This 3-digit code represents the consecutive day of the year, from 001 (January 1) to 365 (December 31).
For example, January 1st would be coded as 001, and December 31st coded as 365. August 1st would be 213.
By law, all USDA graded eggs must display the pack date prominently on the carton. Knowing the Julian date helps determine an egg's age.
Checking the Julian Code
To find the Julian date, look for a number between 001 to 365 on the carton. By law, it must be printed in numerals, not inked or stamped.
Check the plant code next to it - that indicates which processing facility packed the eggs. Now you can easily reference the Julian date to determine freshness.
So if you see the code 289, that means the eggs were packed on October 16th (the 289th day of the year). Combined with the sell-by date, you can estimate the eggs' age.
Storing Eggs Correctly
Proper storage from the get-go helps maximize any egg's lifespan. Here are tips for keeping eggs fresh longer:
Refrigeration is Key
Always store eggs refrigerated at 40°F or below. Consistent cool temperatures preserve freshness and prevent bacterial growth.
Eggs kept at room temperature age faster as moisture evaporates through the shell. Refrigeration slows this process down.
Watch the Location
Where you keep eggs in your fridge makes a difference. The optimal storage location is in the body of the refrigerator, not the door.
The door's temperature fluctuates more, which can hasten quality decline. The back of the bottom shelf is ideal - coldest yet with minimal moisture loss.
Know When to Toss Them
Even refrigerated, eggs have a limited shelf life. It's best to use eggs within 3-5 weeks for peak quality.
After that, discard any expired or questionable eggs. Don’t take risks with older eggs that may have turned rotten.
Following proper storage and handling, most eggs stay fresh 4-5 weeks beyond the pack date. But when in doubt, remember the float test and sniff check don't lie.
Are Old Eggs Safe to Eat?
What about eggs that pass smell, float, and visual tests but are well past their date? Are they still safe to eat? Let's crack into some concerns over aging eggs.
Bacteria Growth
The main safety risk with older eggs is bacteria like Salmonella. As eggs age, protective barriers weaken, making contamination more likely.
Listeria is another bacteria that can penetrate eggshells over time. Listeria thrives at refrigerator temps and can multiply to unsafe levels in expired eggs.
So even if old eggs look and smell normal, bacteria growth becomes more likely. Don't take risks with very old eggs.
Handling Matters
How expired eggs were handled also determines safety. Eggs must be refrigerated continuously to control bacterial growth.
If eggs sat out unrefrigerated for over 2 hours, discard them. Bacteria multiply quickly at room temperature, especially in aging eggs.
Always cook expired eggs thoroughly until yolks and whites are firm. Raw or undercooked eggs pose the highest risks of foodborne illness.
When in Doubt, Throw it Out
Follow your senses, but it's smart to toss eggs that are older than 5 weeks from the pack date. At that point, it’s not worth taking chances with outdated eggs.
The bottom line? Strictly refrigerated eggs are generally OK to eat for 3-5 weeks beyond the pack date. But older eggs come with increased safety risks that aren't worth food poisoning.
Getting the Most Out of Older Eggs
You don't have to say goodbye to an older egg just yet. Find out the best ways to use and cook with eggs that are past their prime.
Best Uses
While older eggs aren't ideal for frying or poaching, they can still shine in baked goods. Here are some great ways to use aging eggs:
- Quiches, frittatas, and stratas
- Custards, puddings, and ice cream
- Pancakes, muffins, and other baked goods
- Casseroles and meatloaf
- Mayonnaise and creamy salad dressings
The additional air in the whites of older eggs makes them perfect for whipping up fluffy omelets too.
Cooking Methods
To eliminate risks with older eggs, always cook them thoroughly until the yolks and whites are set. Here are some safe cooking methods:
- Hard boil eggs until completely firm throughout
- Fry or scramble eggs over high heat until no runny bits remain
- Bake eggs in casseroles and other dishes at 350°F+ until set
- Cook egg custards and sauces in a double boiler until thickened
- Add eggs at the end to hot soups, sauces, and stir fries after cooking
Heating eggs to 160°F kills any potential Salmonella or bacteria present. So cook older eggs using high temperatures to be safe.
Nutrition of Fresh vs. Old Eggs
Eggs are packed with protein, nutrients, and minerals. But does nutritional value decline as eggs age? Let's crack this egg nutrition mystery.
Protein Content
The protein quality in eggs remains constant as they age. Even expired eggs provide all nine essential amino acids.
Both the white and yolk retain their full protein content over time. So you can still gain 6 grams of filling protein per large egg.
Vitamin Retention
Most egg vitamins stay steady past the sell-by date if refrigerated. However, two vitamins see some minor loss.
Riboflavin declines over time but most remains. Old eggs lose more vitamin D as the fatty yolk breaks down.
Luckily, both these vitamins are heat stable, so cooking eggs doesn't deplete levels further. Overall, eggs past their prime still deliver lots of nutrients.
Cholesterol Content
Egg yolks do contain cholesterol, about 185 milligrams each. But cholesterol doesn't increase as eggs get older.
The yolk's fatty cholesterol content stays constant with age. So while old eggs may not be as pretty, their cholesterol levels hold steady.
For those limiting dietary cholesterol, egg whites provide protein without cholesterol. But dietary guidelines no longer cap daily cholesterol consumption.
Overall Value
Bottom line? Eggs coming up on their sell-by date are still chock full of protein, vitamins, and minerals. Nutrient levels don't suddenly plummet once an egg expires.
A high-quality protein source, eggs can continue nourishing your body even a few weeks past their prime date. Just be sure they’re cooked properly and you'll gain the same nutritional benefits.
Becoming an Expert Egg Freshness Detective
Equipped with all these tips for determining egg freshness, you can now confidently crack into that aging carton in your fridge.
To recap, look for these signs of fresh eggs:
- Sink in water
- Clean, uncracked shells
- Tall, rounded yolks
- Thick, cohesive egg whites
- Minimal odor
- Julian date within 3-5 weeks
While eggs past their prime may need some special handling, they still have plenty to offer nutritionally. An egg-cellent inexpensive protein source, you don’t have to say goodbye to expired eggs just yet.
With the float test, visual and smell checks, date decoding, and proper cooking methods, your eggs can have a delicious second life. Trust your senses, follow safety precautions, and you can easily determine whether an egg is still good or destined for the garbage.
So go on and check that egg carton in the back of the fridge. Chances are some of those “expired” eggs still have lots of appealing possibilities! Turn your aging eggs into fluffy omelets, rich custard, hearty casseroles, and more.
Hungry for even more egg facts? Let me know in the comments your best tips for determining egg freshness. And share how you give new life to older eggs in your own kitchen!
Frequently Asked Questions About Egg Freshness
Got questions about determining if your eggs are still fresh and safe to eat? Here are answers to some common queries on decoding egg expiration dates, safety concerns, storage tips, and more.
How long do eggs last in the fridge?
Properly stored in the refrigerator, eggs typically stay fresh 4-5 weeks beyond the pack date. The Julian date on cartons indicates when eggs were graded and packed. Combined with the sell-by date, you can estimate age. After 5 weeks, it's best to discard old eggs.
Can you eat eggs after the expiration date?
Yes, eggs can be safely consumed several weeks past sell-by and best-by dates if kept refrigerated continuously. Those dates indicate quality rather than safety. Do the float test, check appearance, and smell eggs to determine freshness beyond the date.
Do older eggs need to be cooked differently?
Older eggs may not be great for frying or poaching since the whites thin out. Use well-aged eggs in baked goods, custards, and scrambled dishes. Always cook eggs thoroughly until yolks are firm regardless of freshness. That kills any bacteria present in older eggs.
Why do older eggs get runny and watery?
As eggs age, carbon dioxide and moisture escape through the porous shells. This makes the whites thinner and runnier. Fresh eggs have thicker whites and tighter yolk membranes that keep everything nicely centered. Older eggs spread out more due to declining quality.
How long can you keep hard boiled eggs in the fridge?
Hard boiled eggs stay fresh in the fridge for up to one week. To extend the shelf life of cooked eggs, refrigerate them in an airtight container covered with water. The water prevents air from degrading the eggs. Discard any hard boiled eggs that give off a sulfur smell when peeled.
What causes green around the yolks of hard boiled eggs?
A greenish discoloration around hard boiled yolks results from overcooking, not age or spoilage. When eggs are boiled too long, iron and sulfur compounds react, forming greenish-gray ferrous sulfide. It's harmless but undesirable. Avoid green yolks by not overcooking.
Can you freeze eggs to make them last longer?
Only raw whole eggs can be frozen, not hard cooked ones. Freeze eggs quickly in airtight containers up to 1 year. Thaw frozen eggs overnight in the fridge before using. Freezing stops the aging process and preserves freshness longer once thawed. But frozen egg whites may become thick and gummy.
Is it safe to eat eggs with runny yolks?
Runny egg yolks are only safe to eat if the eggs are very fresh. As eggs age, bacteria like Salmonella can more easily penetrate the shells and contaminate the insides. Cook until yolks are completely firm to kill any potential bacteria in old eggs.
Why do eggs develop a sulfur or rotten smell when bad?
A potent sulfur odor in spoiled eggs comes from hydrogen sulfide gas produced by bacteria as eggs rot. If you detect this "rotten egg smell," discard ASAP. It means the eggs have decomposed to unsafe bacterial levels and should not be eaten.
Can cracked eggs be salvaged if the insides look normal?
Eggs with large cracks should not be consumed as bacteria can enter through the damaged shell. But eggs with tiny "hairline" cracks on the wider end can still be safe if kept refrigerated. Inspect the inner contents before eating. Discard at any sign of unpleasant odor or abnormal appearance.
Are there any other questions about determining egg freshness I can help answer? Let me know in the comments!