Peeling boiled eggs
As an egg ages, carbon dioxide leaks out through the shell and the white turns more alkaline, from about pH 7.6 toward 9. That makes the white cling less to the shell membrane, so eggs 1 to 2 weeks old peel cleanly. Very fresh eggs tear.
Chill the eggs in ice water
Ice water stops the cooking and makes the white pull slightly away from the shell. Chill the eggs 5 to 10 minutes, tap the shell all over, then peel under a thin stream of water so the membrane slips off with the shell.
Test yourself
Questions from the interactive lesson, with the answer and the why.
You want deviled eggs with smooth, unpitted whites. Which eggs do you boil?
Eggs that are about 1 to 2 weeks old. Their whites let go of the shell membrane.
True or false: After hard boiling, a very fresh egg is harder to peel than a week-old one.
True. Fresh egg white sticks tightly to the shell membrane.
What went wrong? You boil eggs laid yesterday and leave them on the counter to cool. Peeling takes chunks of white with it.
The eggs were very fresh and were not chilled in ice water. Older eggs and an ice bath both help the shell come off.
Fill the blank: After boiling, an ice bath stops the cooking and helps the ___ come off cleanly.
After boiling, an ice bath stops the cooking and helps the shell come off cleanly. The white pulls away from the shell membrane.
You only have very fresh eggs and want them to peel easily. What helps most?
Steam them, then chill in ice water right away. Steam heat followed by a cold shock loosens the shell.
