NASA-Funded Scientists Turn Plastic Bottle Waste Into 'Edible' Cookies, Human Taste Tests Set to Follow

Scientists have turned plastic bottle waste into cookie-like food using engineered yeast, but no one has been allowed to taste the strange space-age snack yet.

Researchers at Southern Illinois University Carbondale say they have created 'edible' cookies from upcycled plastic as part of a NASA-funded project designed to help feed astronauts on long missions. The work was funded through NASA's Deep Space Food Challenge, which asked scientists to develop food systems that could support crews travelling far from Earth.

For a Mars mission, that problem becomes urgent. A round trip could take around three years, making it impossible to rely only on conventional food supplies.

'When an astronaut goes to Mars, they have to survive in extreme conditions,' said Dr Lahiru Jayakody, the microbiologist who led the project. 'You have to use everything you have.'

How Bottles Become Cookies

The process begins with polyethylene terephthalate, or PET, the common plastic used in single-use water bottles, food packaging and some clothing fibres. The plastic is first broken down through a process using heat, water and oxygen. That turns the tough material into smaller carbon-rich molecules that microbes can digest.

The team then feeds those molecules to specially engineered yeast. Using gene-editing methods, the yeast has been reprogrammed to convert plastic-derived carbon into biological ingredients such as proteins, fats and acids. Those nutrients are mixed with starch, fibre and sweetener, then pushed through a 3D printer to form small disc-shaped cookies.

The researchers also used another yeast strain to turn plant biomass into vanilla flavouring.

'It Smells Like a Real Cookie'

The team has not eaten the cookies yet because it is still waiting for institutional approval for human testing.

'We haven't eaten them yet because we're awaiting approval for testing in humans,' Jayakody said before presenting the work at a meeting of the American Chemical Society in Chicago.

Still, the early reviews are not entirely grim. The researchers said the cookies have scored well on aroma. 'I think it has a pleasant, appealing aroma,' Jayakody said. 'We've not tasted it, but it smells good – that's for sure – like a real cookie.'

The team printed the cookies in the shape of the Greek letter µ and called them 'µBites', or micro bites.

Not Ready for Supermarket Shelves

The idea may sound like a solution to two problems at once: plastic pollution and future food shortages. Jayakody said global food demand is expected to rise sharply by 2050, while a large share of the world's population could face hunger. He believes microbes may help address that challenge.

But the technology remains expensive. The cookies currently cost around $60 per kilogram to produce, though the team hopes improved yeast efficiency and larger-scale production could bring that down.

Some experts are sceptical about how far the idea can go. Jason Hallett of Imperial College London warned that the world produces about 400 million tons of plastic waste each year.

'You're not going to turn it all into cookies,' he told New Scientist.

The researchers say plastic-derived food may be more realistic in specialised settings than in everyday diets. Possible uses include space missions, submarines, disaster zones or other places where supplies are limited and waste must be reused.