Everyone has a tip for making the "perfect" hard-boiled egg. Do an internet search--it's overwhelming. Unfortunately, my eggs are often hit or miss. They always taste great (do to my "secret" ingredients), but sometimes they look like I tried to shoot the shell off with birdshot. (For the record, I've never tried it...maybe it works!) Therefore, I have decided to approach the problem scientifically. (I may have spent too many semesters working in the physics lab.)
First, identify the problem. I want eggs that are easy to peel.
State a hypothesis. I think that there is something to the old wisdom that older eggs are easier to peel. There is plenty of anecdotal evidence to support the theory.
Create an experiment. I chose to try two cooking methods: baking and boiling. I also wanted to know if the eggs peeled easier immediately after they are cooked, or if they peel easier after having chilled in the fridge overnight. I used four eggs for each method: two older eggs purchased a week ago, and two newer eggs purchased yesterday. One of each was peeled while still slightly warm, and the other was chilled in the fridge overnight. I also included two new eggs cooked in a separate pan with baking soda in the water, which was rumored to help make fresh eggs peel better. I made a chart and numbered each egg with a Sharpie.
For the baking method, I used a tip I found on Pinterest. Place the eggs in a muffin tin, bake at 325 for 25-30 minutes. It is interesting to note that the fresh eggs exuded some kind of moisture through the shell during the baking process, which then browned. The old eggs did not. (Both the old and new are the same brand, from the same local farm.)
The next day I peeled the other half of the eggs. The boiled eggs all had peeling issues, but the older egg looked the best. The egg boiled in baking soda practically fell apart during the peeling process, and was unusable for deviled eggs. The baked eggs fared a little better, but the shell stuck to the scorched parts. (You can see the scorch marks on egg #4 below, lower center.)
Conclusion: I accept the hypothesis that older eggs are easier to peel. Baking the eggs did make them easier to peel, but left scorch marks that I was not happy with. (I wonder if using a silicone muffin pan would make a difference? Or possibly rotating the eggs during cooking time?) Fresher eggs had less greying of the yolk, so it almost seems like you have to chose between a pretty white or a pretty yolk! It is also worth noting that across the board the eggs were easier to peel while they were still slightly warm...cold eggs stuck to the shell much more than warm ones. (Baking soda in the water was completely useless, and possibly sabotaged the process!)
Remember, every egg is different, and it is impossible to make exact comparisons. But, I think it is safe to say that boiling older eggs and peeling them right away is the way to go.
And now, I will share my "secret" deviled egg tips!
Tip #1: Zip top bag. As you slice the eggs and remove the yolks, place them directly into a ziptop bag. Close the bag and smash just the yolks until smooth and they start to clump together.
Tip #2: Miracle Whip and Dijon Mustard. Yes, most people use mayonnaise, and that is where they go wrong. Also, yellow mustard is so overdone. Try using miracle whip and dijon mustard...you will never go back. You can also try different flavors! One of my favorites is pesto with miracle whip. I have also used salsa and cream cheese, and it was awesome!