The water test for egg freshness Very fresh eggs will sink to the bottom and lay on their sides. If an egg stays at the bottom but stands on its small end, it's still acceptable to eat; just not quite as fresh.
Carefully lower your eggs into fresh cold water using a spoon (you can do this in the pan if you're about to boil them). If the eggs stay at the bottom they're fresh; if the eggs float, however, they're stale and best avoided.
If you put an egg in a cup of tap water, it will sink to the bottom. Why is this? Because the density of the egg is higher than the density of tap water, so it sinks. Density is the mass of a material per unit volume.
If it sinks to the bottom, turns on its side, and stays there, it is very fresh. If the egg sinks but floats at an angle or stands on end, the egg is a bit older (a week to two weeks old) but still okay to eat. If the egg floats, it's too old and should be discarded.
Food Safety
The Standard for the egg industry is the Food Standards Code: Standard 4.2. 5– Primary Production and Processing Standard for Eggs and Egg Products. This Code is legislated which means egg farms or businesses that process eggs or egg products must uphold all requirements listed in the document at all times.
This process of water moving through a membrane is called osmosis. Osmosis equalizes – or makes the concentration of water on both sides of the egg membrane the same. This means the egg will swell as the water moves inside and get larger.
You can eat eggs past their expiration date. Just be sure to keep your eggs egg-cellent by storing them correctly. If you don't know if an egg is good or not, you can try the float test or give it a whiff. If it doesn't pass the test, throw it away.
Place your eggs in the water. If your eggs sink to the bottom and lie flat on their sides, they are very fresh. If your eggs stand on one end at the bottom, they are a few weeks old, but still fine to eat. If your eggs float to the surface, they are no longer fresh.
The theory is that, as an egg ages, the air pocket inside it grows larger, buoying an old egg to the surface. But, according to Dr. Schaffner, “there is no scientific basis for the egg float test.” So experimenting to see if your egg sinks or swims is not a reliable way to measure its quality.
If the eggs sink to the bottom and lay flat on their side, they're still fresh. However, if they sink, but stand on one end at the bottom of the glass or bowl, they're not as fresh but still edible. Of course, if any eggs float to the top, they shouldn't be eaten.
An unwashed egg will last for 6 months or more in the refrigerator. If the fresh eggs have been washed, then the shelf life will be similar to a store bought egg - about 4-5 months.
Judging the freshness of your eggs
Semi-fresh eggs: Eggs which are semi-fresh should sink to the bottom but stand up straight. Older eggs: If your egg floats higher than halfway towards the surface of the water this means it's most definitely not fresh and consumption should be avoided.
Old eggs should always be disposed of responsibly to avoid contamination and food-borne illnesses. You can choose to compost, feed them to animals, recycle them at local centers, or throw them in the trash. Eggs with foul odors or discoloration may be spoiled and should not be eaten.
The best way to determine if your egg is spoiled is by cracking it open into a bowl. If the egg white is pink or iridescent this is an indication of spoilage due to Pseudomonas bacteria. Some of these bacteria can make us sick when eaten and they will produce a greenish, fluorescent, water-soluble color.
As an egg ages, this air cell grows larger as the yolk and white further contract. Therefore, an older egg is less dense and more likely to float in boiling water. Store-bought eggs can last several weeks beyond their sell-by date or expiration date. To reduce the chances of eggs going bad, keep them refrigerated.
Result: The egg becomes stained with cola and can be removed by the toothpaste. *You could add in an extension activity to this, where you get kids to leave the egg in cola for 24 hours.
The acid in the vinegar reacts with the calcium carbonate in the shell. This reaction produces a gas called carbon dioxide! STEP 3: After 48 hours, remove the egg and rinse it off. Ours had a layer of brown scum that was easily washed away!
The whole eggs we use in our breakfast McMuffins are cage-free and 100% Aussie, from suppliers like Pace Farm and Sunny Queen Farms.
In Australia, most egg producers recommend storing eggs below 15C. This makes the fridge the best place for them. The Australian Eggs organisation also recommends a “climate-controlled refrigerated environment” for storing eggs.
Here's What Fresh Eggs Daily Tells Us:
By law, an egg can be sold for up to 30 days after the date it was put in the carton. And farmers have up to 30 days to go from when the egg is laid to the carton. That means those supermarket eggs can be two months old by the time you buy them.