Additionally, there is the candling method, which is used primarily for testing egg quality before putting eggs on the market, but it could help determine freshness too, though its more difficult to see at later stages. Some just put a flashlight right next to the eggshell to light up the insides, but historically, a piece of cardboard with a small hole in it was used, with a light source behind it and the egg in front. Image via Womans Institute Library of Cooking 1. The above method will let you see the air space and mold, but its really a difficult technique to get down. Image via Womans Institute Library of Cooking 1. 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. The Best Method for Cracked Eggs The Plate Sniff Test. If you dont need the shell intact, you can also crack the egg onto a plate or other flat surface to test how fresh it is. If its fresh, the yolk should be bright yellow or orange and the white shouldnt spread much. If youre not sure, give it a good sniff fresh eggs shouldnt have much of a smell at all. Image via Rouxbe. If the egg is older, the yolk will be flatter and the white will be much more runny. An egg that spreads out when cracked isnt necessarily bad, though, just older and again, good for hard boiled eggs. If its gone bad, you probably wont even need to do the sniff testeven slightly rotten eggs will have a very strong, distinct smell youll notice right away. What to Do with Eggs That Expire Soon. Got a bunch of eggs that are going to go bad before you can use them Hard boil them and throw them in a jar with a beet brine to make tangy, delicious, and beautifully purple pickled eggs. Image by Yumi SakugawaWonder. How. To. There are also lots of things you can do with those discarded eggshells, like make your teapot super clean, fertilize soil, and make sidewalk chalk. And dont forget about those leftover egg cartons, which make good seed and fire starters, bird feeders, and candle making molds. Do you know of any other ways to test whether or not an egg is good to eatShare your method with us in the comments. Cover image via Our Little Coop.