Cookies produced from recycled plastic may seem like something straight out of a dystopian sci-fi plot. But researchers say they have managed to create such a product as part of a NASA-funded project aimed at feeding astronauts on future space missions. The technology uses specially designed yeasts to transform plastics and agricultural waste into proteins, fats and edible flavorings. The resulting slurry is passed through a 3D printer to create a disc-shaped “cookie.” “My lab works on developing technologies for plastic recycling,” said Dr. Lahiru Jayakody, a microbiologist at Southern Illinois University Carbondale, who led the project. “We thought, why not look into food? Plastic is carbon and food is carbon.” The team has not yet received institutional approval to test the plastic-derived cookies, but reports that they “receive high marks for aroma.” “We haven’t eaten them yet because we’re waiting for approval to do human testing,” Jayakody said, ahead of a presentation of the work Monday at the American Chemical Society meeting in Chicago. The method to transform plastic waste into nutrition was funded as part of NASA’s Deep Space Food program. Challenge, which invited scientists to develop new food technologies to solve the feeding problems of astronauts on long trips. “When an astronaut goes to Mars, he has to survive in extreme conditions,” Jayakody said. “The round trip is three years. You have to use everything you have.” In this case, the researchers took one of the most common forms of plastic, polyethylene terephthalate (PET), which is typically the only ingredient in single-use water bottles. First, PET is “digested” through a process that involves water and oxygen at high temperature and pressure to break down the tough material into smaller, carbon-rich molecules. They are then fed yeast, which have been genetically reprogrammed to use the plastic-derived molecules as food. The yeast converts the carbon in the plastic into new biological molecules, including proteins, fats and other nutrients, which can be mixed with starch and transformed into edible products. A different strain was used to produce vanilla flavoring from plant biomass. Currently, the cookies cost $60 per kilogram to produce, but improving yeast efficiency and increasing production is expected to reduce the cost in the future. The team suggests that, in addition to long-distance space travel, the concept could be useful in extreme environments on Earth, such as submarines or disaster zones, or even as a conventional ecological solution to the dual challenges of plastic waste and food production. “Global food demand is expected to increase by 35% to 56% by 2050, and around 30% of the world’s population will be at risk of hunger in the future,” Jayakody said. “I think the way to address this is by using microbes.” However, the team recognizes that before cookies gain widespread acceptance, the public may need to get used to the concept of eating foods derived from plastic.
