International Space Station Prepares ‘Space Miso’ With a Twist, the First Food Deliberately Fermented Outside Earth

Scientists are always trying to understand how several earthly things will pan out in space. Recently, they included a dish in the list, stated CNN. Findings regarding this new entry have been published in the iScience journal.

Scientists, Maggie Coblentz, from the Massachusetts Institute of Technology (MIT) and Joshua Evans, from the Technical University of Denmark, sent a container of cooked bean paste to space in 2020, which resulted in the formation of possibly the first-ever miso paste in space. The paste was made in the International Space Station (ISS), and is believed to be the first edible that has been fermented outside Earth. Researchers are hopeful that this preparation will allow more culinary options for astronauts and also shed more light on the possibility of life in space.
Miso paste is composed of koji, salt, water, and soaked soybeans. It is estimated that the paste takes six months to come to fruition. The longer, the paste ferments, the better will be its flavors, as per experts. It is a popular Japanese cuisine, with each region having its own special dish centred around the miso.
Miso, the traditional Japanese seasoning, has officially become the first fermented food created in space.
— Essential Japan (@EssentialJapan_) April 2, 2025
Researchers from the Massachusetts Institute of Technology (MIT) confirmed on the 2nd of April that they had successfully produced miso on the International Space Station. pic.twitter.com/DIdk4Nw9aQ
The study claimed that the paste was fermented for 30 days in space. The people who tasted the 'space miso' noted some similarities as well as differences with the earth miso paste. According to them, the space miso had the savoriness of its earth counterpart, however, there was a stronger roasted and nutty flavor in the extraterrestrial preparation. The container in which the miso was stored had sensors to monitor aspects like radiation, relative humidity, pressure, and temperature.
To compare the space miso with earth miso, the scientists used similar ingredients to create miso batches in Cambridge, Massachusetts, in the U.S, and Copenhagen, Denmark. "We didn’t know what to expect — fermentation had never been done before in space," said Joshua. D. Evans, the co-lead author of the study. "The space miso one was darker and clearly more jostled, which makes sense, as it had traveled much more than either of the earth misos. It was exciting to smell and taste the first bite."

According to Evans, the space miso was a little different because the fermentation was influenced by factors such as microgravity and increased radiation. These reasons possibly affected the growth of microbes and hence could give insights regarding life forms in space. "By bringing together microbiology, flavor chemistry, sensory science, and larger social and cultural considerations, our study opens up new directions to explore how life changes when it travels to new environments like space," Evans said.
The authors also think that the space miso will help astronauts in the future. It will give the astronauts a healthy choice of food and encourage new forms of culinary expression in space. This is not the first time scientists have experimented with food in space. In the past, many kinds of lettuce and radishes have been harveted in the world beyond by astronauts. In 2021, ICC organized a taco party to celebrate the harvest of chile peppers in space.