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FOOD SCIENCE

Not All It's Cracked up to Be

By Brian Geiger, contributor

December 18th, 2009

Kitchen Mysteries is a weekly exploration of oddities surrounding cooking and food. They could be recipes that fail when they shouldn't, conflicting advice from different sources, or just plain weirdness. If it happens in a kitchen, and you're not sure why, send a tweet to The Food Geek to find out what's happening.

 

I've heard something from many reputable sources that's meant to be kind of a mini-revolution in food preparation technique. Most recently, it was from Foodimentary on twitter, a great little "learn something about food every day" feed. In any case, one day Foodimentary writes:

The theory goes that, if you crack an egg on a sharp edge, that sharp edge not only breaks the shell, but pushes a piece of shell up into to edge. However, if you crack the egg on a flat surface, the egg does crack, but as nothing is going into the center of the egg, the shell remains on the outside.

This makes a certain amount of sense, and I've been doing it for the past few years, but I've never really gotten the hang of it. I seem to get at least as many egg shell pieces in the egg as before. And as I thought about it more, I've come up with a counter* theory.

You see, just on the inside of the egg is a thin membrane that protects the egg from wee beasties like bacteria and viruses. It also causes problems when you're peeling hard-boiled eggs. What it really does well is to stick to the egg shell itself.

When you crack an egg on a corner, you make a very defined point of breakage. There can be some around the edge, but with all the force concentrated on one line, it's likely that not only will the egg break there, but the membrane will be torn there as well. No matter how many little pieces are created, as long as they are still connected to that membrane, they won't get released into your egg.

When you crack an egg on a flat edge, the egg cracks in many places, and it's unlikely that the membrane will break at a defined point. You either have to force an edge with a finger, or you have to tear the egg apart. With either method of separation, the membrane is going to separate somewhat randomly instead of on a straight line, which increases the chances of allowing a piece of shell to separate from the pack.

Because it's egg nog season, I've been cracking many eggs the past couple of weeks. I've tried both methods, and I have to say that the edge method is easier for me and with no troublesome egg fragments. How about you? Have you switched from edge cracking to flat cracking? How did that work out? Has anyone switched back to edge cracking?

*-Ha!

posted in: Blogs, food geek, egg, shell, membrane, crack
Comments (11)

SarahEllsworth writes: I guess I'm the odd woman out here - I LOVE cracking eggs on a flat surface. Over the past 6 months (when I first started cracking eggs on the counter), I have literally only had to fish one piece of a shell out. I think it works because it doesn't actually break the egg - it only damages the shell just enough that I can gently wedge my thumb in and pull the shell apart, yielding one clean break. But I guess it's only me that's had this kind of success! Posted: 10:11 pm on March 23rd

TheFoodGeek writes: Loreena, that's fantastic. I had never heard of that before. I can't say that I'm going to follow in your footsteps, but I love it even so. Posted: 9:21 pm on March 22nd

loreena writes: If I am cracking several eggs, I usually crack them against each other - hold one in each hand and bang them lightly together. The one that gets cracked is the one that gets opened. Of course if there is an uneven number of eggs, the last one has to be done some other way. I do both flat and edge cracking when necessary. I find that either work ok if I do not hit the egg too hard on either the flat or the edge. It takes a certain quick, sharp, yet light touch to prevent little pieces of shell going into the egg. Posted: 8:10 pm on March 22nd

cookslots writes: I switched to flat surface cracking on the side of the sink. I'm hooked and even though there is occasional shell in the egg, it is easy to remove and rinse down the drain. Posted: 9:14 pm on January 6th

TheArdentWanderer writes: Sorry Alton Brown, but i've also tried flat cracking with mediocre results. I'm back to edge cracking. I think the key is just to remember that it's an 'egg' and not go too Neanderthal either way. A delicate hand with the edge technique works best for me. Posted: 7:00 pm on December 27th

Pielove writes: I agree with you, Lisa, and hkmouse-- thank you for debunking this piece of dubious kitchen wisdom. Posted: 2:46 pm on December 21st

BasementBaker writes: One swift crack on the edge is all it takes. Posted: 4:52 pm on December 18th

t_mauery writes: In high school, I learned how to crack eggs one-handed, without getting any shells mixed in. Now that I have observant kids that are prone to experiment, I have returned to the more conventional one egg-two hands approach. In doing so, several sources convinced me that flat cracking was the best method, and I've found that I've had to fish shells out more in the past few months than I have over the last decade.

It's back to edge cracking for me. Posted: 4:25 pm on December 18th

LpAngelRob writes: I've had better results with consistently cracking eggs on the counter than the bowl - a few times the shell would fall in cracking on the edge of the bowl, but more often it was just plain messier.

That said, each egg is different. Sometimes cracking an egg on a flat surface resulted in one nice crack around 3/4 of the egg. Sometimes it resulted in a 2-inch-wide divot.

-Rob Posted: 3:57 pm on December 18th

LisaWaddle writes: Thanks for addressing this, Brian. I've gone through the same experimentation as you. I'm back to edge cracking, after years of trying to stick with flat cracking. Edge cracking is just more dramatic, which equals fun in my book! (Love the pun!) Posted: 1:25 pm on December 18th

hkmouse writes: I tried flat cracking. After picking many shell bits out of the mixing bowl, I thought I was just doing it wrong and went back to edge cracking. Glad to know it's not just me! Posted: 10:48 am on December 18th

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