**Know how to determine if your egg is still good or bad**

Am here to share with everyone how to determine if our egg is is good or bad.
Mum bought a create of egg for me to take along to school after our summer break,on getting to school I arranged them inside a container and well ventilated to avoid spoilage, but after some months I discovered that after cooking the egg, I won't be able to eat it because of the bad aroma it produces which irritate anytime I perceived it or flash back to the event, so I decide to go on research to know how to keep egg in order to last long and how to know if it has spoil or is still good.
Besides, almost everyone has been faced with this egima — you reach into the fridge for an egg, but can't remember how long they have been sitting there lot of people rely on the date on the packaging to tell them when food has gone bad, even with eggs, but the "sell by" dates are often rather arbitrary, and do not correlate to expiration dates. If you've been tossing away your eggs based on the dates on your carton—you're wrong.
We can use our eyes and nose to determine freshness with meats or fishes, but you can't really use your senses to test an egg before you crack it (unless you're highly skilled).
So I will be sharing the best, easiest and simplest methods to test if your egg is OK or not.

The first method is the float test
Just fill a bowl with cold water and place your eggs in the bowl and drop the egg slowly in the water. If they sink to the bottom and lay flat on their sides, they're very fresh. If they're a few weeks old but still good to eat, they'll stand on one end at the bottom of the bowl. If they float to the surface, they're no longer fresh enough to eat.
Below are the picture of the research for better understanding

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How it works
The float test work as egg ages, the air space at the end enlarges. This gives the egg enough buoyancy to float on water. Fresh eggs have a tiny airspace. They are therefore able to sink and rest horizontally at the bottom. Eggs that have stayed for quite some time will sink but rest vertically since their airspace is big. Rotten eggs, however, have the biggest airspace and therefore will float.
The big question is that can the float test fail??
The answer is YES.. Why?? The float test will not be effective when one is using salty water. This is because salty water is dense and makes all eggs float whether they are fresh or bad. In case you do not have fresh water available, use the candle or and sniff test.

The Candle Test
As the name suggests, the candle test for egg freshness involves illuminating your egg shell with a candle light or flashlight in a dark room. The method works depending on how thick or spotted your egg shell is. If it is too thick or spotted, you will not be able to use the method.

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For a fresh egg, the contents do not move freely even when you tilt. This is because it has a small air space. For a rotten egg, however, the contents move freely since there is a lot of air space.

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Above you can see a fresh egg (little air space, slightly visible yolk), a slightly old egg (larger air space, slightly darker yolk), a nearly bad egg (really dark yolk, spotty), and a spoiled egg (mixed in yolk, lots of dark) using the candling technique.

Conduct a sniff test
The sniff test can be said to be the oldest, simplest and reliable method to confirm if the egg has gone bad or not.. If probably your eggs are past their "sell by" or expiration date you can as well tell if they are still good with a sniff test
If you can't already tell while the egg is in the shell, crack the egg onto a clean plate or bowl and give it a sniff.
If anything smells off, toss the egg and wash the bowl or plate with hot, soapy water before using again.
If things smell normal, meaning there is no odor at all, that's a good sign that the egg is still safe to use.
A lack of knowledge about how to tell when an egg has gone bad leads some people to needlessly throw away good eggs.
Among the three strategies listed here, float test, candle test, giving it a sniff and is the most conclusive method of determining freshness.
Keep in mind though that eggs containing bacteria that cause food-borne illness, such as
Salmonella , may look and smell completely normal.
So don't forget that even if an egg passes these tests, it's important to fully cook it to a safe temperature before you eat it.
There are somethings you can make with the discarded Egg shell e.g to make your teapot super clean, to make a sidewalk chalk and finally to fertilize soil
Reference(studyfaq.com)(http://metro.co.uk/2016/06/17/how-to-tell-if-eggs-are-fresh-5951076/)