What do you give an astronaut who heads out for a six-month mission into space to aid nutrition? The answer could lie in Muscadine grapes.
In 2016, NASA searched for shelf-stable foods to keep astronauts healthy. North Carolina State University researcher Dr. Mary Ann Lila and her team developed a possibility: Protein bars with Muscadine.
“They have such a diverse profile of chemicals [naturally],” says Lila, director of N.C. State’s Plants for Human Health Institute, located at the North Carolina Research Campus in Kannapolis
“These are the same chemicals that interact with [diseased cells to be modified or treated]. Once you eat that grape to counteract chronic human disease, those same chemicals that protect the plant, protect the human body,” says Dr. Lila. “A Muscadine grape, in particular, has a very diverse phytochemical profile, including ellagic acid, which is an anticarcinogenic, antihypertensive,” says Lila
Phytochemicals are compounds found in plants said to counteract diabetes, improve cognitive function and improve the immune system.
Astronauts, who work in tight spaces, can easily share germs.
Lila says that Muscadine was a good choice to include in their nutritional intake because it aids the immune system.
It was important to deliver a potent mix of phytochemicals in fruits and vegetables in a shelf-stable form.
“We took edible proteins, which they need in a space environment, and fused them with phytochemicals from Muscadine grapes, cranberries and blueberries,” says Lila.
The easiest manner to combine the phytochemicals and proteins would be to melt them together. But phytochemicals lose their health benefits when exposed to heat.
So, Lila’s team bound the compounds to an edible protein source without heat to ensure its nutritional value would not degrade throughout the duration of a mission. The blended substance acts as a building-block ingredient, like flour in a baked good.
Next, the team tackled shelf-stability. These bars needed to remain edible after months or even years in space.
“We found protein was the issue,” says Lila. “Any high-protein product becomes unpalatable, tough or brittle after a month-and-a-half of storage. That’s a problem for long-term missions to Mars. You [need products] that will maintain their flexibility and be palatable over a period of time.”
But the unique properties of Muscadine held a key.
Scientists found polyphenols, naturally occurring chemicals in plants, from Muscadine prevent cross-linking with proteins and allow the “…bars [to] remain nice and flexible during long-term storage,” says Lila.
This became useful in other applications. “We use it for smoothies,” says Lila. “We use it for crisps. We use it for just about anything you put protein in, but the high-protein products tend to be bars or smoothies, like what athletes will drink.”
There was an unexpected byproduct of the research.
The protein that the researchers fused with the polyphenol acts like a shield throughout the journey through the digestive system. This means astronauts will reap more nutritional benefits from the Muscadine grapes.
Lila doesn’t know if the bars have made their way into space yet. But their potential applications back on Earth abound, from sports nutrition to cosmetics and pharmaceuticals.
“There’s a great interest in using fruit-active compounds for skincare, for wound healing, for skin resilience,” says Lila.
Like anything, once your foundation is secure, the possibilities are endless.
Last Updated: May 8, 2023
