NASA Spinoff

Water Treatment Technologies Inspire Healthy Beverages

NASA Technology

If you wandered the halls of Johnson Space Center in the mid-1990s, you might have run across Mike Johnson lugging a large container of freshly collected urine down to the lab. There, Johnson assisted the scientists who were tasked with developing technology to convert the waste into drinking water. Johnson’s role earned him a unique nickname that follows him to this day—“the Pee Man.”

altThough the idea of drinking reclaimed urine is unsettling for those of us with easy access to water on Earth, the research conducted by the Advanced Water Recovery Systems Development team has proven vital to space exploration. Thanks in part to their work, astronauts in low Earth orbit make the most of their resources, and those who will take part in future missions—like a trip to an asteroid or Mars—can count on having drinkable water for the journey.

The team in Houston specialized in using microorganisms to purify water. One breakthrough in the project involved the use of a unique technology: a trickling filter bioreactor. This cylinder-shaped unit is filled with porous spheres—providing a large amount of surface area for biofilm growth—and utilizes the wastewater itself as a growth medium for the bacteria.

Whereas fixed-plate cultures grow bacteria on a twodimensional surface, the trickling filter bioreactor’s media provides significantly more area for growth, and the reactor design reduces limitations to the movement of fluids and gases. The resulting environment proves more conducive to the growth of the organisms, which can propagate in all directions and tend to form in healthier cultures.

In fact, Johnson says, the bioreactor proved too effective: “The results were so good, and the bacteria propagated so quickly, that it clogged the unit unless we cleaned it out much more frequently than we expected.” The unanticipated growth rates meant that the scientists would have to recalibrate their system. It was at that time, however, that Johnson decided to change careers. He left NASA and attended chiropractic school, eventually opening up his own practice in Minnesota.

Technology Transfer

Though his days working in a science lab were behind him, the experience Johnson gained at NASA would soon come in handy. In addition to his work as a chiropractor, he also served as a healthcare practitioner by advising patients on nutrition. Given his background in wastewater regeneration, he was particularly sensitive to the issue of unhealthy drinks.

“I saw a lot of my clients consuming Coke, coffee, or other sugary drinks,” he says. “But when I tried suggesting alternatives, I found there weren’t many healthy beverages I could point to.”

As Johnson pondered the situation, he thought back to his days of turning undrinkable waste into something healthy. “We used bacteria to remove the bad stuff from urine; so I thought, why not use probiotics to add healthy stuff to a drink?” (A probiotic is a microbe that protects its host and prevents disease.)

The experiment started in the back of his chiropractic office, where Johnson began growing probiotics in 55-gallon oak wine barrels. He used the bacteria to brew batches of kombucha—a live, cultured tea that has been fermented by bacteria and yeast—and filled empty beer bottles with the results. Johnson gave out samples to his patients, happy that he finally had a healthy drink to endorse. He says they were hooked right away: “People kept coming back—the next week, the next day—wanting more, because it had made them feel so much better.”

In order to produce higher quality bacteria, and produce more of it, he looked to the trickling filter bioreactor from Johnson Space Center for inspiration. Johnson says he used the expertise he gained at NASA to custom build his own bioreactor, but on a larger scale. At 750 gallons, it holds nearly 40 times as much fluid as the one the team in Houston used.

Starting with a large cylinder, he connected pumps to the bottom and filled the whole chamber with his nutrient solution. With the pumps continuously circulating the fluid, Johnson’s probiotics moved freely throughout the tube. “I couldn’t have my bacteria fixed to a plate,” he says, “because it was too slow and the probiotics didn’t eat nutrients fast enough.” The result was stronger, higher quality cultures that further enhanced his drink.

One day, unbeknownst to Johnson, one of his patients decided to take her free sample back to her employer, Whole Foods Market. The local store of the grocery giant immediately showed interest. Soon after, Johnson founded Unpeeled Inc. in Minneapolis-St. Paul, Minnesota, and his NASAenhanced drink began appearing on the shelves at Whole Foods, as well as other local specialty food stores.