Space Miso: Astronauts Ferment Japanese Soybean Paste on ISS, a Culinary Milestone for Space Missions

Astronauts aboard the International Space Station (ISS) have successfully fermented miso, a traditional Japanese soybean paste, marking the first deliberate food fermentation in space. This culinary experiment, which could revolutionize astronaut diets on long-duration missions, involved sending a mixture of soybeans, rice koji, and salt to the ISS in March 2020. Researchers selected miso for its microbial diversity, solid structure (minimizing leakage), manageable fermentation time, distinctive flavor, and high nutritional value. Analysis of the space-made miso revealed differences in microbial ratios compared to Earth-made miso. However, the space miso retained its identity and was deemed safe for consumption. Interestingly, the space miso exhibited a more roasted and nutty aroma, influencing its flavor profile. This breakthrough holds significant implications for future long-duration space missions, such as voyages to Mars, by enabling astronauts to produce their own nutritious and palatable food. The ability to ferment food in space addresses the challenge of food monotony and potential nutrient deficiencies, enhancing the well-being and performance of astronauts during extended space travel. This also opens doors to new possibilities in space food systems, offering not just nutrition but comfort, variety, and a connection to Earthly traditions.