Speaker 1: Welcome to brain Stuff from How Stuff Works, Hi brain
Speaker 1: Stuff Lauren Vogel bomb here. A manned mission to Mars
Speaker 1: might take around six months. Suffice it to say, when
Speaker 1: meal times roll around, astronauts won't be dialing up delivery
Speaker 1: pizza and root. Instead, they may be eating nutrition derived
Speaker 1: from their own fecal matter, a concept that would save
Speaker 1: on cargo, space and wait while maximizing materials already found
Speaker 1: on the spacecraft. At Penn State University, scientists are developing
Speaker 1: a system that leverages certain types of microbes that convert
Speaker 1: human solid waste into protein and fat Latin foods. Researchers,
Speaker 1: for better or Worse, have already called the result a
Speaker 1: microbial goo that's sort of reminiscent of vegemite, a comparison
Speaker 1: that seems unlikely to please vegemites corporate executives. Because it's
Speaker 1: difficult and time consuming to grow food in space, astronauts
Speaker 1: have to rely on items in their closed environment. The
Speaker 1: lynch pin of the system is anaerobic digestion, which can
Speaker 1: break down certain materials with the need for oxygen. It's
Speaker 1: a common process for reducing municipal waste on Earth. In tests,
Speaker 1: the digestion process produced methane gas. That gas turns out
Speaker 1: to be useful in growing a microbe called Methylococcus capsulattice,
Speaker 1: which is already used for animal feed pellets and contains
Speaker 1: about fifty protein and thirty six percent fat content. According
Speaker 1: to the National Academy of Sciences, humans function best when
Speaker 1: they ingest nutrition with about fifty percent carbohydrates, twenty percent fat,
Speaker 1: and ten to thirty protein, So the goose still has
Speaker 1: a ways to go before it can count as an
Speaker 1: ideal food source. The tests relied on substitute liquid and
Speaker 1: solid waste instead of actual human wastes. When the real
Speaker 1: thing is introduced, there will also be concerns about pathogens
Speaker 1: that could cause illnesses. That's where tweaking the pH levels
Speaker 1: and or temperatures may help. Tests showed that by increasing
Speaker 1: the system's temperatures to around a hundred and fifty eight
Speaker 1: degrees fahrenheit that's seventy degrees celsius, most germs were eliminated,
Speaker 1: yet the nutritious microbe Thermois aquaticus survived. Alternately, they raised
Speaker 1: the alkalinity of another batch and found that bacteria called
Speaker 1: halo Monus deciderrata still managed to proliferate, while germs did not.
Speaker 1: The team borrowed concepts from commercial aquarium filters that use
Speaker 1: fixed film filters to neutralize fish waiste. The filters incorporate
Speaker 1: a bacteria laden film and were adapted by researchers to
Speaker 1: accommodate methane production. The result solid waste can be treated
Speaker 1: in a matter of hours instead of days plus. Because
Speaker 1: the system is self contained, it really doesn't require much
Speaker 1: babysitting other than you know, the necessary inputs. But there's
Speaker 1: also the matter of taste. Lisa Steinberg, the lead author
Speaker 1: on the study, says that the bacteria could be mixed
Speaker 1: with other materials and flavorings to make it more palatable.
Speaker 1: She said in an email, it's nearly certain that there
Speaker 1: would be plants grown in conjunction with this food stuff,
Speaker 1: which would provide additional flavors and textures. And what about
Speaker 1: the potential psychological issues associated with consuming a material of
Speaker 1: such dreary origins, Steinberg said. Astronauts ready have to drink
Speaker 1: their own processed urine, so they're probably accustomed to things
Speaker 1: being done differently in space than on Earth. Some astronauts
Speaker 1: on the International Space Station do already recycle some of
Speaker 1: their urine. Poop, on the other hand, has a more
Speaker 1: spectacular ending. It's blasted into space, caught an Earth's orbit,
Speaker 1: and then burns up like a shooting star on reentry. Yes,
Speaker 1: in space, poop has historically been a problem. Maybe now
Speaker 1: poop will be part of the solution. While these still
Speaker 1: experimental concept may not exactly fire up astronauts appetites, it
Speaker 1: may eventually provide sustenance to space explorers who have a
Speaker 1: limited buffet options among the stars. Today's episode was written
Speaker 1: by Nathan Chandler and produced by Tristan McNeil. For more
Speaker 1: on this and lots of other tasty topics, visit our
Speaker 1: home planet, how stuff Works dot com.