Carry out taste tests to explore how our senses affect the flavour of our food, and what this might reveal about eating in space.
From the early 1960s, astronauts found that their taste buds did not seem to be as effective when they were in space as they were on Earth.
On Earth, gravity pulls on the fluid in our bodies, moving it down into our legs. In space, this fluid is spread across the body. This is called Fluid Shift. This change can be seen within the first few days of arriving in space, when astronauts have a puffy face as fluid moves into the face (this is called Moon Face). The puffy face feels to astronauts like a heavy cold and it can cause taste to be affected in the short term by reducing their ability to smell. After a few days the fluid shift evens out as the human body adapts. In the long term, taste is largely affected by the other odours in the small station (e.g. body odours, machinery). The sense of smell is very important to tasting food.
When food seems to lose its flavour, astronauts ask for condiments, such as hot sauces, honey, soy sauce and BBQ sauce.
UK National Curriculum, KS2 Biology, “Animals including humans: recognise the impact of diet, exercise, drugs and lifestyle on the way their bodies function”.
There are no refrigerators or ovens on the International Space Station, but that isn’t the only reason that eating can be a strange experience for astronauts. Due to lack of gravity and shifting fluids, things can taste very different in space. In this activity students will carry out a taste test to explore how our senses affect the flavour of our food, and what this might reveal about eating in space.
Adapted from NASA and Mission X, train like an astronaut.
STAY HEALTHY! Before handling any food products, please thoroughly wash your hands.
FOOD SAFETY! Each member of the group can taste the liquids (unless they are allergic to the food).
1. Fill each of the five bowls with a different type of food. Label the bowls 1-5 and on the back of the label write down the item in the bowl. Place a napkin over each bowl to act as a lid, hiding the food inside.
2. Place the bowls around the room with lots of space around each one.
3. Split the class into groups of 3. Give each group one blindfold, one cup of water, 3 pipettes, 3 worksheets and 3 pencils.
4. One member of each team will wear a blindfold to taste each item (helped by other members of the team), and one member of each team will peg their nose when tasting each item.
5. Send two groups to each bowl to begin.
6. Each student will taste the food items in all 5 bowls, noting down the intensity of flavour (0-10, 0 for least intense, 10 for most intense), noting the taste (sour, bitter, sweet etc.) and guessing the food item.
Conclusion
By the end of this activity students should understand how fluid shift in microgravity environments such as the International Space Station can affects the experience of eating by reducing our ability to taste food. Students should also understand how our senses of smell and sight affect the flavour of food.
Finish this activity with a discussion session to find out what students learned:
When results have been collected from all students, enter them into the Flavour Intensity spreadsheet to create a graph demonstrating any differences in intensity of flavour based on lack of sight or smell. Invite the class to discuss the following questions:
- Did everyone give each food the same intensity? Why?
- Did everyone guess the correct food or flavour? Why? Which flavours appear to be strongest?
- Did lack of smell affect the results? How? Why? Did lack of sight affect the results? How? Why?
- Do you think you could live in space despite the effect it has on your taste?