‘Cookies’ made from plastic may be on the menu for future astronauts

Scientists at Southern Illinois University Carbondale have unveiled a prototype cookie they call μBites, a protein‑rich snack built from shredded polyethylene terephthalate (PET) bottles, corn stalks and a suite of engineered yeasts. The idea emerged from a NASA‑funded effort to devise food that can be fabricated where traditional supplies are impossible to ship, whether in a disaster‑struck city, a submarine or a multi‑year deep‑space mission.

The core chemistry hinges on the fact that both plastic and biomass are essentially carbon stores. Researchers first subject the mixed waste to oxidative hydrothermal dissolution – a high‑temperature, high‑pressure water‑oxygen treatment invented by geology professor Ken Anderson – which cracks the polymer chains into small molecules that microbes can ingest. Those fragments are then fed to yeast strains such as Saccharomyces cerevisiae, S. boulardii and the oleaginous Rhodosporidium toruloides, each engineered to reroute carbon into proteins, lipids, vitamins and aroma compounds.

Because PET supplies are virtually limitless and agricultural residues are abundant, the process promises a closed‑loop food source that does not depend on fresh water or arable land. In microgravity experiments, the same yeast platforms have already produced insulin and other pharmaceuticals, demonstrating that a single bioreactor could churn out both medicine and nutrition for crews on the Moon or Mars. “Microbes are very clever,” remarks associate professor Lahiru Jayakody, underscoring the strategy of letting biology do the heavy lifting that chemists once performed.

Beyond the immediate appeal for space travel, μBites illustrate a broader vision where plastic waste becomes a feedstock for everyday nutrition, potentially easing pressure on conventional protein sources. Yet several hurdles remain: large‑scale reactors must prove economic viability, regulatory agencies need definitive data on long‑term health impacts, and consumer acceptance will hinge on taste tests that are still pending. If those gaps are closed, the technology could turn the billions of tons of discarded PET into a resilient, on‑demand food supply, reshaping both waste management and food security strategies.