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Exploration of the Month

October 1998

animated pumpkin

The World's Favorite Snacks

The hours after trick-or-treating were some of the best moments of Halloween. It was then that we emptied out all of the goodies from our pillowcases and counted up our plunder. On rare occasions, we were trilled to get a bag of chips or a pack of cookies. (They seemed more extravagant than a Tootsie Roll) This month's page is dedicated to the Oreo, the number one cookie in the world, and Fritos, the number one snack food on the planet.

Crunchy on the outside, creamy on the inside...that's what an Oreo represents - the best of both worlds! Every year, 9.1 billion Oreo cookies are produced by Nabisco. Since their creation in 1912, over 362 billion of these delicious little cookies have been made. More, interesting Oreo facts can be found at their web site. They are not just good to eat but good to look at as well. The outer, chocolate part is very decorative as shown below.

oreo cookie wrapper oreo cookie enlarged cookie print

Perhaps even more interesting in appearance however is an Oreo examined with the scanning electron microscope. The pictures below show the complex surface of the cookie. These rough areas look like a whole bunch of crumbs stuck together.

SEM cookie X350 SEM cookie X700 SEM cookie X2000

The inside of an Oreo is perhaps the best part. The sweet vanilla cream has inspired such variations as Double Stuff Oreos and Halloween Oreos (with the orange colored cream). However, without a microscope the composition of the cream is hard to observe. The next images are enhanced photographs of the cream. What's in an oreo cookie, you ask? The package of every food product distributed in grocery stores has a nutrition label on it. It contains dietary information (amount of fat, calories, vitamins) and a listing of ingredients (the highest by weight listed first and the least used being last). The ingredients for one Oreo cookie are the following: It might surprise you to see chocolate as the last ingredient on the list! That means it has the lowest amount of any ingredient in an Oreo!

SEM cream under optical  SEM cream X200 SEM cream X800

Fritos packaging Fritos corn chips

The Fritos' history is almost as interesting has the Oreo. The number one snack chip in America got its start in 1932 when Elmer Doolin paid one hundred dollars for the recipe. Today, that small investment has blossomed into the Frito-Lay Corporation, which controls over fifty percent of the world's snack market. The ingredients are simply corn, vegetable oil, and salt.

Below are some pictures taken with the scanning electron microscope. To be quite honest, they are not as interesting as we here at Project MICRO hoped them to be. But, we can see small irregularities on the chip's surface. The lighter rectangular object on the left is different. Upon further magnification, the object has depth too and a crystalline structure. We can guess that this is the salt used for the chip's flavoring. It is similar to the table salt at our homes which also have a regular crystalline composition.

frito SEM X200 frito SEM X500 frito SEM X200

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Last Updated: 10/01/98

Special thanks to Guiz Creations for the pumpkin animation