Changes in Taste Perception in Astronauts
Scientists from Australia have discovered that changes in taste sensations in astronauts can be caused not only by microgravity, but also by individual food perception characteristics and stress from isolation. This finding not only increases the comfort of the flight for astronauts, but also directly affects their health. Consuming enough calories becomes problematic if food causes unpleasant sensations. Sauces and seasonings partially solve this problem, but their use is limited due to the possibility of allergic reactions. This is especially relevant for long missions to the Moon or Mars.
The individual reactions of astronauts to changes in taste are unexpected: some feel significant changes, while others feel almost none. Regular food can become unpleasant for some, but for others, it can change its taste or become a favorite. Until now, the mechanism of these changes has remained unknown, despite over 60 years of research on space flights.
Research has shown two main reasons for changes in taste in space conditions. Firstly, microgravity leads to a redistribution of fluids in the body, which can affect taste perception. Secondly, the conditions of food storage and preparation in space conditions also influence its taste properties. However, these explanations are not exhaustive.
Researchers from the Royal Melbourne Institute of Technology proposed a hypothesis that changes in taste may be related to individual taste and smell perception characteristics that are heightened under the influence of stress from isolation. They conducted an experiment using a simulation of the International Space Station in virtual reality. 54 participants evaluated the intensity of smells in «neutral» laboratory conditions and in conditions of virtual reality simulating the ISS. The results showed that the intensity of almond and vanilla smells increased in virtual reality conditions, while the citrus smell remained stable. This suggests that stress and isolation can increase sensitivity to certain aromatic substances.
This discovery opens up new research directions in this area. An important aspect is the difference in reactions to flavorings: vanilla and almond contain benzaldehyde, which citrus does not. This may explain why some smells become more intense under stress.