Space Miso: What Fermented Food from the ISS Tastes Like

Miso is one of the most traditional Japanese foods, prepared in the same way for centuries – but now the savory soybean paste has made its way into space. A miso fermentation process was recently carried out aboard the International Space Station (ISS).

The goal: to find out how microbial processes like fermentation behave under microgravity – and what that could mean for the future.

Fermentation Among the Stars

In March 2020, a research team sent a mixture of soybeans, rice kōji, and salt to the ISS for 30 days to see whether fermentation would work in space. Back on Earth, the results confirmed success – showing that microbes and non-human life can operate even in space.
Miso was the ideal candidate, as it’s a naturally fermented product that heavily relies on microorganisms. While microgravity alters microbiological processes – which can affect flavor, texture, safety, and shelf life – fermentation could offer a sustainable solution for food supply on long-term missions. It takes up little space, lasts long, and benefits the microbiome.

What Does Space Miso Taste Like?

The space-fermented miso, which spent six months aboard the ISS, was compared to samples fermented under identical conditions on Earth. The surprising result: the flavor differed only slightly, with the space version described as especially “nutty” and “roasted”. Texture and appearance also remained largely the same – a strong indication that fermentation can succeed beyond Earth.

What This Means for the Future

Long-duration space missions, such as those to Mars, present major challenges for nutrition and food storage. Fermented foods like miso could play an essential role – thanks to their long shelf life and positive effects on the microbiome. At the same time, the experiment opens up new possibilities for food production in isolated or extreme environments, such as polar research stations or future moon bases.

One Small Step for Miso...

...one giant leap for humankind? The successful fermentation on the ISS shows that tradition and technology aren’t mutually exclusive – and could help improve food quality and variety in space.

And who knows – maybe miso will soon be a staple on the intergalactic menu.