Food - Drink
The Reason Some Eggs Are Harder To Peel Than Others
By KAREN GRECO
While it's much easier to hard-boil an egg than to poach one, getting the shell off is often the tricky part. Heating the egg causes the proteins to form strong bonds, making them edible, while the proteins also bond with the membrane around the shell during this process, making them hard to peel.
Pete and Gerry's recommends waiting a week after purchasing eggs before boiling, because as eggs age, the pH level rises, weakening the bonds so they separate easier. However, if you can't wait for your eggs to age, adding something alkaline to the water, like baking soda, can help ease apart the links between the proteins, making shelling easier.
Alternatively, you can hard-cook the eggs by steaming them instead of boiling, as the steam loosens the bonds between the whites and the membranes. You could also try giving hard-boiled eggs a post-cook ice bath, which not only stops the eggs from cooking, but it causes the membrane around the egg to shrink and separate from the shell.