It can take 12-24 hours before a good portion of the shell is removed. A good sign of progress is a white frothy scummy layer on the top of the surface of the vinegar. After a day of soaking you can carefully remove the egg from the vinegar.
If you soak an egg in vinegar the eggshell will absorb the acid and break down, or dissolve. The calcium carbonate will become carbon dioxide gas, which will go into the air. What is left is the soft tissue that lined the inside of the eggshell. It will bounce!
STEP 1: Place an egg in the jar and cover with vinegar. Optional: You can color the vinegar with food coloring for rainbow-colored rubber eggs too! STEP 2: Wait and watch! Notice the bubbles on the eggshell!
My curiosity, however, was piqued by another matter. Yes, the egg is bigger. But after being vinegared, sugared, and soaked, is it edible? The short answer, according to food safety experts, is no.
Leave the egg in the water for 24 hours. The water will migrate from the side of the membrane where water molecules are abundant (outside the egg) to the side where water molecules are less abundant. After 24 hours, the egg will be plump again.
How it works is by adding acid to the egg yolks — either in the form of lemon juice or vinegar. Adding acid raises the temperature at which egg yolks cook, so we can heat them to 140°F, killing the bacteria, but without cooking the egg.
What is this? Soak your hard boiled eggs in vinegar for 5-10 minutes. The vinegar is essential in helping the colors adhere to the shell.
Egg Peeling Method #3: Boiling Eggs with Vinegar
Adding white vinegar or apple cider vinegar to your pot of water allegedly results in softer, easier-to-peel eggshells. That's because the acid in vinegar dissolves some of the calcium carbonate that makes up the egg's hard exterior.
Pickled eggs should never be at room temperature except for serving time, when they should be limited to no more than 2 hours in the temperature danger zone of 40 to 140 degrees F. Caution: Home pickled eggs stored at room temperature have caused botulism.
If you look closely at the egg while it's submerged in the vinegar, you can see bubbles forming on the surface. Those bubbles are full of carbon dioxide, just like the bubbles in a glass of soda. You're seeing a reaction between a compound in the eggshell (calcium carbonate) and an acid in the vinegar (acetic acid).
Pickled eggs must be kept refrigerated and should not be left out at room temperature. The Centers for Disease Control and Prevention (CDC) recommends the eggs be left intact and not poked or pricked, or otherwise handled in a manner that might allow spores or bacteria into the yolk.
*While the best vinegar for Easter egg dyeing is white, apple cider vinegar does work because it contains the same acidity necessary for the acid dye to work.
It's not just to keep the kids dunking instead of drinking, it turns out. Most food dyes are acid dyes, so called because they only work in acidic conditions. The vinegar---a solution of 5 percent acetic acid in water---is there to bring the pH low enough that the dye will actually bind.
You should use warm or hot water.
You can't just mix the food coloring or egg dye with water at any temperature. Warm water helps the dye to absorb better than cooler water. Also, it's recommended that the water should always be warmer than the temperature of the eggs for the same reason.
"Vinegar is an inherently acidic material, so if we add a few drops of vinegar into that boiling water that is going to increase the rate of denaturing and it's going to make that happen faster and help the poached egg hold its shape better."
Add salt and vinegar to the water before cooking.
I already talked about this above. The salt permeates the shell a little bit, and the vinegar helps to break down the shells, making them easier to peel.
Osmosis will occur; that is, the water will migrate from the side of the membrane where water molecules are abundant (i.e. outside the egg) to the side where water molecules are less abundant (inside the egg). After 24 hours, the egg will be plump again!
4 minutes for slightly set yolk and set white. 5 minutes for a medium cooked firmer yolk and white. 6 minutes for hard boiled with lightly soft yolk. 8 minutes for firmly hard boiled.
Is washing of eggs recommended? No, because washing may aid the transfer of harmful bacteria like Salmonella from the outside to the inside of the egg. The priority in egg production is to produce clean eggs at the point of collection, rather than trying to clean them afterwards.
So it is not a good idea to re-use the vinegar as you may bring about fermentation in the ensuing batch. Once you've eaten all the pickles, you could use the remaining vinegar to start a mayonnaise, brine a chicken, flavour a potato salad or liven up a dip.