Miso fermented in house has a novel taste

Researchers are exploring how fermented meals like miso might develop into part of astronauts’ diets. Credit score: Maggie Coblentz

The traditional culinary follow of fermentation might play a task in the way forward for house delicacies.

In March 2020, an interdisciplinary workforce of researchers despatched a small batch of substances for the Japanese condiment miso to the Worldwide Area Station (ISS). Within the first experiment of its type, the miso spent 30 days fermenting aboard the orbiting laboratory and was flown again to Earth for extra evaluation — together with style assessments.

Research members found that the batch fermented in orbit had the attribute savory taste of miso, however tasted noticeably nuttier then equivalent batches that had remained on Earth to ferment. There have been additionally variations within the microbial and chemical profiles, the researchers discovered.

In a paper revealed in iScience on April 2, the workforce stories they will’t make sure what precisely triggered the variations. However, they are saying, it demonstrates that fermenting meals in house is possible — and that would result in more healthy, tastier meals for astronauts.

A brand new frontier for fermentation

The “house miso” challenge was began by Maggie Coblentz, a researcher on the MIT Space Exploration Initiative and co-lead creator of the examine. “I used to be interested by increasing meals merchandise for astronauts past the freeze-dried army ration model,” she stated.

Fermentation emerged as a potential avenue when Coblentz started collaborating with meals researcher Josh Evans of the Technical College of Denmark. They questioned whether or not fermenting meals in house might present a manner of bringing extra taste, microbial variety, and dietary worth to the astronaut food regimen.

On Earth, demand for fermented meals and drinks is rising, from kimchi to kombucha, pushed partly by curiosity of their contributions to intestine well being and sustainable meals practices.

However little was recognized about how fermentation would work in house. Experiments carried out in labs on Earth had instructed that microgravity might alter the method. However fermentation on the ISS had not been tried earlier than.

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When a chance to ship an experiment to house got here up, the workforce selected to ship fermenting miso for a number of causes.

The primary was sensible, says Evans. As a paste, miso is much less prone to leak than fermented drinks, decreasing the chance of damaging different experiments and tools on the ISS. And the method of fermentation for miso was match for the 30-day window they’d out there for the experiment.

There have been scientific concerns as effectively, provides Evans, who research how completely different ecosystems of microbes affect the flavour of fermented meals. A latest surge of analysis about miso fermentation allowed the workforce to check their space-fermented miso and put their outcomes into context.

Then there have been the culinary causes: Utilized in soups, sauces, and marinades, miso is nutritious, has a robust umami taste, and a wealthy cultural historical past.

Bringing fermentation to house

Miso is constructed from cooked soybeans, salt, and koji — a fermentation starter made from a grain like rice or barley that has been inoculated with a fungus known as Aspergillus oryzae.

“The general course of has two primary steps,” Evans stated. “First you develop the koji, which wants air. Then whenever you combine the substances and pack the combination into the fermentation container, the salt and lack of oxygen kills the koji and lets micro organism and salt-tolerant yeast take over to proceed the fermentation.” 

These micro organism break down the sugars within the beginning combination into different compounds, together with people who give miso its savory taste. The precise taste of a miso can range primarily based on a batch’s distinctive microbial tradition, in addition to a wide range of environmental components that might be completely different in house.

For the experiment, the workforce in Denmark ready a batch of miso of round 2 kilos (1 kilogram), and divided it into three parts. In March of 2020, one portion went as much as the ISS for 30 days, one went to Coblentz in Massachusetts, and one stayed in Denmark with Evans.

To observe the house setting, Coblentz and Evans introduced engineers and meals scientists onto the workforce. They constructed what they known as “sensing packing containers” for the miso parts that went to house and stayed in Massachusetts. The packing containers recorded temperature, humidity, stress, and radiation within the setting all through the 30-day fermentation course of.

All three batches had been frozen earlier than and after the 30-day experiment window to attenuate the variations between batches.

Style assessments

The house miso was not consumed onboard the ISS. However by working to establish potential challenges or issues of safety involving fermented meals in house, the workforce hoped to carry them a step nearer to the ISS menu.

When the workforce analyzed the microbial cultures of the misos again in Evans’ lab, they discovered that the three miso microbial communities had been related and had most species in widespread, virtually all coming from the Staphylococcus genus. Nevertheless, solely the miso fermented on the ISS contained a species often known as Bacillus velezensis, which had been recognized beforehand in fermented soy meals. The authors assume this may occasionally have been as a result of the temperature contained in the sensing field onboard the ISS unexpectedly rose to 97.3 levels Fahrenheit (36.3 levels Celsius) — in comparison with the parts on Earth, which had been saved at between 68 and 77 F (20 to 25 C).

The completely different misos additionally had variations in aroma and taste. A gaggle of 14 panelists that the workforce assembled described the house miso as having a nutty, roasted aroma and a stronger umami style in comparison with the 2 Earth misos. 

These variations might have been mirrored within the chemical compounds discovered within the misos. The house miso contained larger concentrations of compounds with cheese-like flavors (2-methylbutanoic acid) and honey-like flavors (methyl phenylacetate).

Future frontiers

Whereas the authors of the examine concluded that miso might be fermented in house, they don’t seem to be positive how or whether or not components like microgravity and radiation affected the fermenting miso’s particular properties. Then there was the undesirable warmth that reached the miso, plus a bumpy trip with excessive g-forces to and from orbit, and different environmental variations.

“All we will say is it’s completely different there than it’s right here. However there’s so many the reason why that might be, and doubtless it’s all these issues working collectively,” Coblentz stated.

Researchers wish to perceive how these components altered the miso earlier than astronauts really begin fermenting their very own substances. Astronauts’ meals provides are tightly managed as a result of the dangers of getting sick in house are a lot larger than on Earth. As an illustration, when kimchi was flown to the ISS in 2008, it was blasted with radiation earlier than flight to kill micro organism and stop the cabbage from persevering with to ferment onboard. The surprising change within the miso’s temperature reveals that the fermentation course of wasn’t saved below excellent management — one thing that may must be addressed when bringing fermented meals to the ISS.

Fermentation is a course of that’s naturally delicate to adjustments in its setting, notes Andrew MacIntosh, a fermentation skilled on the College of Florida who was not concerned within the examine. “Area opens up an entire new avenue,” he stated. “And a whole lot of the worth that we see on this paper is the difficulties that these researchers went by means of attempting to glean details about how house can be completely different.”

MacIntosh sees this as a step towards a potential future through which house exploration might be extra self-sustaining and fewer depending on deliveries from Earth. Microbial communities concerned in fermentation might be harnessed and engineered to supply substances for meals and even prescription drugs, he thinks.

Coblentz says their work might additionally assist make house extra welcoming for vacationers by providing extra selections for meals, whether or not by means of producing it by way of fermentation or just enhancing its taste. “Drawing upon our deep earthly historical past of working with meals and fermentation throughout completely different cultures world wide — it has kind of a poetic facet to it,” she stated.