Food tends to taste bland in space, astronauts have reported, making it tough for them to eat enough to stay healthy.
Focusing on foods' smell might help overcome this problem, a new study says.
Aroma plays a big role in the flavor of food, and researchers found that certain scents might be more powerful in the cramped confines of a spacecraft.
Vanilla and almond aromas were more intense when study participants donned virtual reality goggles that simulated the confined setting of the International Space Station, researchers found.
On the other hand, a lemony scent was perceived the same as always, results show.
These findings indicate that the isolation and loneliness of space travel might play a role in astronauts' lack of appetite, researchers concluded.
The VR experiment "really does go a very long way to simulating the experience of being on the space station,"said researcher Gail Iles, an associate professor with RMIT University in Australia. "And it really does change how you smell things and how you taste things."
Despite carefully designed diet plans, astronauts aren't eating enough during their voyages, researchers noted.
"What we're going to see in the future with the Artemis missions are much longer missions, years in length, particularly when we go to Mars, so we really need to understand the problems with diet and food and how crew interact with their food,"Iles said in a university news release.
Until now, astronauts' lack of appetite has been chalked up to weightlessness, researchers said in background notes.
Weightlessness causes fluid to shift to the upper parts of the body, which triggers facial swelling and nasal congestion that affect the sense of taste and smell, researchers said.
These symptoms typically begin to disappear within a few weeks aboard the space station, but "astronauts are still not enjoying their food even after fluid shift effects have gone, suggesting that there's something more to this,"said lead researcher Julia Low, a senior lecturer with RMIT.
For the study, researchers asked 54 adults to strap on VR goggles that simulated being in the space station. They were then exposed to different food odors.
A particular sweet chemical in the aromas of vanilla and almond, called benzaldehyde, might explain this change in people's scent perceptions during the space simulation.
"We believe that it's this sweet aroma that gives that highly intensive aroma within the VR setting,"said researcher Jayani Chandrapala, an associate professor with RMIT.
These findings, published July 16 in the International Journal of Food Science and Technology, could help produce food that will be more appetizing to people in space, Low said.
"One of the long-term aims of the research is to make better tailored foods for astronauts, as well as other people who are in isolated environments, to increase their nutritional intake closer to 100%,"Low said.
These results also could help boost the appetites of Earthbound people who struggle to eat enough, researchers added.
"The results of this study could help personalize people's diets in socially isolated situations, including in nursing homes, and improve their nutritional intake,"Low said.
More information
NASA has more on deep space food systems.
SOURCE: RMIT University, news release, July 16, 2024