The Science Behind the U.S. Military's Super Sandwich

Chris McGrath, Getty Images
Chris McGrath, Getty Images

The U.S. military has a fraught history with food. During the Civil War, soldiers munched on tooth-cracking hardtack and salt pork. By World War II, it was SPAM and M&Ms. During the Cold War, the military introduced the world to survival crackers, a.k.a. Doomsday Biscuits.

But there’s always been one problem with most of the items on the menu: Few tasted very good. Hardtack regularly contained worms. Soldiers liked to call SPAM “ham that failed the physical.” The Chicago Tribune once claimed that survival crackers were “better as weapons.”

The challenge facing battlefield rations—called “Meal, Ready-to-Eat,” or MREs—has always been multifaceted. The Seattle Times explains it nicely: "To qualify for MRE duty, a food item has to be able to survive years of storage in a dank ship’s hold or a sun-baked shipping container, withstand Arctic freezes and tropical monsoons, stave off assaults by insects, and remain intact through a parachute airdrop or a free fall from 100 feet.” Taste, as a result, has been woefully neglected.

In 2002, researchers at the U.S. Army Soldier Systems Center in Natick, Massachusetts took the first tangible steps toward fixing that by concocting the world’s first “Super Sandwich.” Resembling a hot pocket, the prototype—which contained fillings like pepperoni and chicken—could last up to two or three years in temperatures of 78 degrees without spoiling or getting soggy. (At 100 degrees, its shelf life dropped to six months.)

For the food scientists working on the problem, the enemy in the battle to make the Super Sandwich was water—specifically, water activity. Put simply, water activity is a measurement of how easily moisture migrates from one food product to another. The higher a food item's water activity, the more likely it’ll give away moisture. The lower the water activity, the more likely it’ll absorb water.

Water activity is a huge hurdle for foods that contain multiple components. Take Raisin Bran, for example: Raisins are moist and have a relatively high water activity. The flakes, on the other hand, are crunchy and have a low water activity. Under normal circumstances, these two components will trade moisture, with the raisins turning hard and the flakes soggy.

The same problem faced the Super Sandwich. “The water activity of the different sandwich components needs to complement each other,” then-project officer Michelle Richardson told New Scientist in 2002. “If the water activity of the meat is too high you might get soggy bread.”

The trick to stopping the problem is to introduce a humectant, a type of substance that reduces a food item's water activity without reducing the actual water content [PDF]. In the case of Raisin Bran, food scientists solved this problem by dusting the raisins in a fine coat of sugar [PDF]. For the Super Sandwich, military scientists introduced both sugar and salt as humectants that successfully curbed creeping moisture and prevented bacterial growth. To further combat spoilage, they placed packets of iron fillings inside the packaging, which helped absorb unwanted oxygen.

Today, the Super Sandwiches—part of the military’s “First Strike” rations—reportedly come in four flavors: Bacon Cheddar, Pepperoni, Italian, and Honey BBQ Beef. According to the BBC, when Richardson first ate a three-year-old sample, it was declared a ringing success.

Well, relatively speaking. She described the taste as … “OK.”

This Smart Accessory Converts Your Instant Pot Into an Air Fryer

Amazon
Amazon

If you can make a recipe in a slow cooker, Dutch oven, or rice cooker, you can likely adapt it for an Instant Pot. Now, this all-in-one cooker can be converted into an air fryer with one handy accessory.

This Instant Pot air fryer lid—currently available on Amazon for $80—adds six new cooking functions to your 6-quart Instant Pot. You can select the air fry setting to get food hot and crispy fast, using as little as 2 tablespoons of oil. Other options include roast, bake, broil, dehydrate, and reheat.

Many dishes you would prepare in the oven or on the stovetop can be made in your Instant Pot when you switch out the lids. Chicken wings, French fries, and onion rings are just a few of the possibilities mentioned in the product description. And if you're used to frying being a hot, arduous process, this lid works without consuming a ton of energy or heating up your kitchen.

The lid comes with a multi-level air fry basket, a broiling and dehydrating tray, and a protective pad and storage cover. Check it out on Amazon.

For more clever ways to use your Instant Pot, take a look at these recipes.

At Mental Floss, we only write about the products we love and want to share with our readers, so all products are chosen independently by our editors. Mental Floss has affiliate relationships with certain retailers and may receive a percentage of any sale made from the links on this page. Prices and availability are accurate as of the time of publication.

This Smart Accessory Converts Your Instant Pot Into an Air Fryer

Amazon
Amazon

If you can make a recipe in a slow cooker, Dutch oven, or rice cooker, you can likely adapt it for an Instant Pot. Now, this all-in-one cooker can be converted into an air fryer with one handy accessory.

This Instant Pot air fryer lid—currently available on Amazon for $80—adds six new cooking functions to your 6-quart Instant Pot. You can select the air fry setting to get food hot and crispy fast, using as little as 2 tablespoons of oil. Other options include roast, bake, broil, dehydrate, and reheat.

Many dishes you would prepare in the oven or on the stovetop can be made in your Instant Pot when you switch out the lids. Chicken wings, French fries, and onion rings are just a few of the possibilities mentioned in the product description. And if you're used to frying being a hot, arduous process, this lid works without consuming a ton of energy or heating up your kitchen.

The lid comes with a multi-level air fry basket, a broiling and dehydrating tray, and a protective pad and storage cover. Check it out on Amazon.

For more clever ways to use your Instant Pot, take a look at these recipes.

At Mental Floss, we only write about the products we love and want to share with our readers, so all products are chosen independently by our editors. Mental Floss has affiliate relationships with certain retailers and may receive a percentage of any sale made from the links on this page. Prices and availability are accurate as of the time of publication.