Would You Eat a Cookie Made From Plastic? Scientists Say It Is Edible

Would you eat a cookie made from plastic?

In technical terms, we are already consuming an alarming quantity of plastic, in the form of microscopic and nanoscale particles in our food.

Now, though, researchers at Southern Illinois University (SIU) Carbondale want people to consume it deliberately.

Their answer is a cookie called µBites – pronounced “microbites”, for anyone familiar with scientific notation symbols.

That may sound even less appealing than the insects we may need to eat in future. Yet these cookies undergo extensive processing intended to make them theoretically safe to consume, nutritious and, ideally, tasty.

The project began as part of NASA's Deep Space Food Challenge, and the team has now presented it at a symposium organised by the American Chemical Society.

“Converting (biodegradable) food-grade plastic into food is feasible,” Lahiru Jayakody, a microbiologist at SIU, told ScienceAlert.

“The µBites system is a tunable and portable device that integrates all necessary components… These units could be deployed in submarines or disaster relief vehicles to produce on-demand, on-site food.

“The process is particularly suited for using carbon waste in extreme environments such as deserts, the Arctic, or the Antarctic to make food – and yes, potentially one day on Mars or the lunar surface.”

From plastic waste to µBites cookies

Plastic is among the modern world's most widespread materials, owing to its versatility and durability. Those strengths become drawbacks at the end of its life, however: most plastic products go to landfill, including recyclable ones.

Recent studies have achieved some success in converting discarded plastic into useful products – not only more plastic, but materials, fuels and even medicines. Food could soon join that list.

Naturally, turning a thrown-away plastic bottle into an edible cookie requires several stages.

First comes a technique developed at SIU known as oxidative hydrothermal dissolution. In essence, it uses oxygen and water at high temperatures and pressures to reduce materials to their carbon building blocks.

For this work, the researchers applied the method to polyethylene terephthalate (PET) plastic and agricultural leftovers such as maize stalks and leaves, creating a liquid feedstock.

That material is then given to cultured yeast, which transforms it into “nutritious food slurries”.

And just like that, there is the starting point for cookie dough.

On its own, the final material may technically be edible, but its taste and nutritional profile would probably be little better than cardboard.

The team therefore engineered separate yeast strains that convert different feedstocks into additional food ingredients, including proteins, lipids, vitamins, aromas, colourings and flavourings.

The feedstock is fed to yeast to make cookies. (SIU Carbondale Communications/American Chemical Society)

For instance, one yeast strain was modified to make the organic compound vanillin, which supplies the scent and taste of vanilla, as its name implies.

Another was engineered to produce beta-carotene, the pigment responsible for carrots' orange colour and one that our bodies convert into vitamin A.

These ingredients are mixed into raw dough, then placed in a 3D food printer, which extrudes it layer by layer into a uniform form.

Finally, the cookie is microwaved, hardening it into the familiar food.

How µBites cookies taste and safety testing

We put the question undoubtedly on everyone's mind to the team: ‘Well, how does it taste?’

Sadly, nobody has been permitted to try one so far – it is likely wiser to wait for the safety testing to finish. Blind sensory testing has indicated, however, that the cookie has a pleasant smell and an agreeable feel.

“We have comprehensively analyzed the food products we created in the lab, as well as through accredited third-party laboratories, to ensure µBites cookies are free from toxic chemicals, heavy metals, allergens, and food pathogens,” Jayakody told ScienceAlert.

“We are conducting simulated digestive studies and other necessary analyses in preparation for human trials.”

A portable food system for extreme environments

Even once taste trials are complete, considerable work remains before people in isolated locations, disaster areas or space are routinely eating µBites.

As it stands, the system takes one or two days and converts more than 50 percent of carbon from waste materials into food products. The researchers intend to raise that figure.

“With future iterations and R&D efforts, we could recirculate the unconverted carbon to achieve nearly 100 percent conversion,” said Jayakody.

“The system is designed to achieve a zero-waste concept; however, approximately 10 percent of the carbon material may be released as waste gas or remain unconverted throughout the process.”

Although the process sounds complex – it currently involves 33 steps – its equipment can be contained within a portable unit suitable for settings with limited space and resources.

The researchers say that making the system function in microgravity is a significant obstacle. In the meantime, however, it has many potential applications on Earth.

Related: Scientists Figured Out How to Turn Plastic Waste Into a Parkinson's Drug

Nor does the approach need to stop at cookies.

“We made cookies as a proof of concept, but the food ingredients can also be used to produce other food items that require protein, aroma, and vitamins, such as milk alternatives and meat alternatives,” Jayakody said.

“Additionally, we are exploring the use of µBites in feed manufacturing.”

The researchers presented their work on Monday at the American Chemical Society's autumn meeting in Chicago. Their work also appears in an industry highlight in Trends in Biotechnology.

This article was fact-checked and edited by Clare Watson. Although we take pride in our process, we are only human. If you notice an error, please let us know.