“Lois, everyone knows there are only two things that can survive a [nuclear] holocaust: cockroaches and Twinkies…”
Not only is this idea perpetuated in season two’s “Da Boom” episode of “Family Guy,” but it’s also a subplot for Woody Harrelson’s character in 2009’s comedic horror “Zombieland.”
In a world-ending event, we seem to find comfort in one thing: as long as there are Twinkies around, we won’t starve. Except, the notion that the highly processed sponge cake is both long-lasting and virtually indestructible is a myth. Twinkies last only about 40 days, and that is an improvement on its original range of about 26 days.
So what should our go-to apocalyptic food be if it’s not a Twinkie? How about macaroni and cheese? Researchers at Washington State University (WSU) have come up with a way to triple the shelf-life of ready-to-eat macaroni and cheese by uniting a revolutionary food sterilization technique with better packaging technology.
The sterilization technology used is called microwave-assisted thermal sterilization (MATS), an in-container food processing technique that uses long wavelength microwave energy and heat to sterilize food. It requires far less exposure time (ten minutes) to high heat, which would otherwise damage the taste, appearance and nutritional value of processed food.
The classical method of retort sterilization (a process involving pressure and heat), on the other hand, requires about an hour for full sterilization. During that hour, food loses a significant amount of nutritional value by comparison. The color and flavor is also impacted, which forces food manufacturers to use color additives and preservatives.
The U.S. military and the WSU researchers behind MATS technology established the Microwave Sterilization Consortium 20 years ago in order to enhance the methods of in-package food sterilization. Their goal was to reduce the amount of heat exposure time, thereby increasing nutritional value and overall food safety. This collaboration helped improve the military’s Meals, Ready-To-Eat (MRE), which prepackaged room temperature ready-to-eat food for soldiers in the field or in battle.
Current plastic packaging technology provides food safety for up to one year. That isn’t bad, but it’s certainly not enough to sustain a world-ending event, or at the very least, get astronauts to Mars. So, researchers had to optimize the packaging. In order to maintain longer ambient storage times, oxygen had to be kept out.
Classical metal packaging wouldn’t work with MATS technology, and glassware was too heavy and occupied too much space. Plastic packaging was the only option for in-package sterilization.
A layer of metal oxide was used to enhance the barrier between food and oxygen. However, when this material undergoes sterilization, cracks form, which eventually diminishes the shelf-life.
For ready-to-eat macaroni to last up to three years, WSU researchers had to work with packaging companies to develop and test alternative films. The result was a film composed of several layers of different types of plastics, each with special characteristics. Some of these characteristics include mechanical strength, sealing capability, barrier ability and printing suitability. Pairing these plastic layers, which are only a few microns thick, with additional layers of metal oxide, researchers were able to develop a packaging material that could preserve food for up to three years.
Three years is a good prospect, but NASA requires storage for up to five years. And when it comes to space travel, food developers face other obstacles: the weightlessness of space, and issues with refrigeration (refrigeration occupies a lot of space and uses a lot of energy).
Remember astronaut ice cream? The failed freeze-dried space snack has become a novelty in museum gift-shops, but it is not the only disappointment to astronauts.Weightlessness in space not only affected the texture of food (which has more to do with processing), but also affected the experience of taste. Without gravity, sinus fluid doesn’t drain properly, causing astronauts to become stuffed up, leaving them to experience taste the same way a person with a cold would. The result was a lot of unpopular food items that were later scrapped, including astronaut ice cream.
What did survive were food items full of sodium and spices such as hot dogs and spaghetti. For short-term space missions, high sodium food isn’t problematic. For missions lasting several months or even years, high sodium food with low nutritional value will not work. To get to Mars, for example, astronauts will need nutritious food options that will last the eight-month journey, the duration of orbit and any mission delays along the way.
Though years-old macaroni and cheese may not seem like the most interesting option, the technology promises that a wider variety of tasty and nutritious food options will arise alongside missions to Mars. Furthermore, with innovative space technology comes commercial spinoffs that in time could expand our apocalyptic menu. When a zombie outbreak arises, we at least won’t starve.
References:
Bohnet, S. (2019, June 13). Washington State University. Retrieved October 11, 2019, from https://labs.wsu.edu/tang/2019/06/13/mat-and-maps-improve-food-preservation/.
Godoy, M. (2013, July 10). The Science Of Twinkies: How Do They Last So Darned Long? Retrieved October 11, 2019, from https://www.npr.org/sections/thesalt/2013/07/09/200465360/the-science-of-twinkies-how-do-they-last-so-long.
Martin, B. (2013, June 1). Unpack a Meal of Astronaut Space Food. Retrieved October 11, 2019, from https://www.smithsonianmag.com/history/unpack-a-meal-of-astronaut-space-food-73348642/.
McLennan, E. (n.d.). Fresh Ideas: Microwave-Assisted Thermal Sterilisation Food Processing Technology. Retrieved October 11, 2019, from https://inside-food.nridigital.com/inside_food_jun18/fresh_ideas_microwave_assisted_thermal_sterilisation_food_processing_technology.
Moncel, B. (2019, October 2). The Twinkie Myth – Will It Stay Fresh Forever? Retrieved October 11, 2019, from https://www.thespruceeats.com/the-twinkie-myth-1328772.
Negron, L. (2019, September 30). Researchers increase shelf life of macaroni and cheese. Retrieved October 11, 2019, from https://dailyevergreen.com/62949/news/researchers-increase-shelf-life-of-macaroni-and-cheese/.
Tripling shelf life of macaroni and cheese. (2019, September 24). Retrieved October 2019, from https://www.sciencedaily.com/releases/2019/09/190924101449.htm.
Understanding the Retort Sterilization Process – Steam Retorts. (2008, September 1). Retrieved October 11, 2019, from http://www.retorts.com/white-papers/understanding-the-retort-sterilization-process-steam-retorts/.
USDA. (n.d.). Washington State University. Retrieved October 11, 2019, from https://labs.wsu.edu/coe/facilities/#MW.