Scientists Turn Plastic Waste Into Edible Cookies Using Engineered Yeast

Scientists have developed an unusual way to deal with plastic waste: using engineered yeast to transform carbon from discarded plastic and agricultural waste into ingredients for protein-rich cookies.

The experimental food, called µBites, is being developed by researchers at Southern Illinois University Carbondale as part of research originally supported by NASA’s Deep Space Food Challenge.

The goal is not to make people eat plastic.

Instead, researchers are breaking down plastic into simpler carbon-containing molecules and using specially programmed microbes to rebuild those molecules into useful food ingredients such as proteins, fats, vitamins and flavoring compounds.

The resulting ingredients are then combined and 3D-printed into cookie-shaped snacks.

How Can Plastic Become Food?

Plastic and food may seem completely unrelated, but both contain carbon.

The researchers focused on polyethylene terephthalate (PET), a common plastic used in bottles and other consumer products.

Rather than putting intact plastic into food, the team first breaks the material down into smaller molecules that microorganisms can use.

The researchers use a process called oxidative hydrothermal dissolution, which combines water and oxygen at high temperature and pressure to break down difficult materials.

The resulting material can then be processed by engineered microorganisms.

Engineered Yeast Does the Unusual Work

Yeast has long been used by scientists as a biological manufacturing system.

In this project, researchers programmed different yeast strains to convert molecules derived from plastic and agricultural waste into useful compounds.

The microorganisms can produce food-related materials including:

• Proteins
• Fats
• Vitamins
• Organic acids
• Flavoring compounds

This means the plastic itself is not simply being ground up and added to a cookie.

Instead, its carbon is being chemically transformed and biologically rebuilt into new compounds.

That distinction is important because the goal is to create a food ingredient from waste carbon rather than have people consume untreated plastic.

The Cookies Are Called µBites

After the microbial process, researchers combine the resulting ingredients with other components such as fiber, starch and sweetener.

The mixture is then processed using a 3D food printer to produce small cookie-shaped snacks called µBites, pronounced “microbites.”

The 3D-printing approach allows researchers to control the shape and portion of the food while working with the unusual ingredients.

The final product is intended to demonstrate how a future closed-loop food system could work in environments where conventional food supplies are difficult to maintain.

Why NASA Is Interested in Plastic-Based Food

The research originated from a challenge connected with NASA’s effort to develop food systems for long-duration space missions.

A spacecraft traveling far from Earth cannot continuously receive new supplies.

Astronauts therefore need systems that use resources efficiently and produce as little waste as possible.

Plastic waste could potentially become a source of carbon for microbial food production instead of simply being discarded.

The same concept could potentially be useful for other environments where supplies are limited.

Researchers have discussed possible applications ranging from submarines and disaster zones to future lunar or Martian settlements.

Scientists Are Also Making the Food More Nutritious

The team is not only trying to produce protein.

Researchers have engineered yeast strains to produce additional food-related compounds.

One yeast strain can produce vanillin, the compound responsible for vanilla flavor, from plant biomass.

Another strain can convert ethylene glycol derived from PET into beta-carotene, a pigment that the human body can convert into vitamin A.

These modifications could eventually reduce the amount of conventional ingredients needed to create a nutritionally useful food product.

The Cookies Have Not Yet Gone Through Human Taste Testing

This is one of the most important details about the research.

Although researchers report that available data indicate the µBites are safe to eat, formal human taste testing has not yet begun.

The team is awaiting institutional approval before conducting those tests.

Researchers have conducted aroma-related assessments, and the early responses have reportedly been encouraging.

So headlines suggesting that scientists are already routinely eating plastic cookies would be misleading.

The project is still an experimental prototype.

Could This Help Reduce Plastic Pollution?

Potentially, but the technology is still far from being a solution to the world’s plastic problem.

PET waste is abundant, and converting some of its carbon into useful products could provide an alternative to simply disposing of it.

However, any future system would need to demonstrate that it can operate safely, economically and at a large enough scale.

Researchers are still working on improving the biological conversion process and developing the ingredients needed for the final food product.

The current µBites prototype should therefore be viewed as a proof of concept, not as a commercially available food product.

What Happens Inside the Process?

The concept can be simplified into several stages.

Step 1: Collect waste

Researchers start with materials such as PET plastic and agricultural waste including corn stalks and leaves.

Step 2: Break the materials down

The materials undergo oxidative hydrothermal dissolution using water, oxygen, heat and pressure.

Step 3: Feed the microorganisms

The resulting carbon-rich molecules are provided to specially engineered yeast.

Step 4: Produce food ingredients

The microorganisms convert the available carbon into proteins, fats, vitamins and other useful compounds.

Step 5: Add additional ingredients

Researchers combine the microbial products with materials such as fiber, starch and sweetener.

Step 6: 3D-print the food

The resulting mixture is printed into the µBites cookie prototype.

This creates a potential pathway from waste material → microbial processing → food ingredients → finished food.

Could Astronauts Eventually Eat These Cookies?

That is one of the long-term goals behind the research.

Future deep-space missions could last much longer than typical missions in low Earth orbit.

Transporting every kilogram of food from Earth becomes increasingly difficult as mission duration and distance increase.

A system that could recycle waste into useful nutrients could therefore reduce the amount of material that has to be carried from Earth.

The researchers envision the technology potentially supporting extreme environments where conventional food production is difficult.

However, the current µBites are still an early-stage prototype and are not ready to become an astronaut food supply.

What About the Moon and Mars?

The concept becomes even more interesting for future settlements.

A lunar or Martian base would have limited access to replacement supplies from Earth.

Researchers could potentially use locally available materials, waste products and microbial systems to create useful resources.

The current project does not demonstrate that a Moon or Mars settlement can manufacture all of its food from plastic.

Instead, it demonstrates one possible component of a closed-loop resource system.

That distinction is important.

The technology would need to become much more efficient, reliable and scalable before it could support a real extraterrestrial settlement.

Could This Technology Be Used on Earth?

Yes, and that may ultimately be just as important as its space applications.

The researchers have suggested potential uses in environments where food production is difficult or conventional supply chains are disrupted.

Possible examples include:

• Disaster-response areas
• Remote research stations
• Submarines
• Resource-limited communities
• Long-duration space missions

The underlying concept is to turn waste carbon into useful biological products rather than treating it solely as garbage.

Why Microbes Are Central to the Idea

Microorganisms are remarkably useful biological factories.

Scientists already use engineered microbes to produce compounds ranging from medicines to industrial chemicals.

In this project, the researchers are using the same basic principle for food production.

Instead of asking a microorganism to simply consume waste, scientists are programming it to produce specific compounds that can become part of a food system.

That makes the project an example of synthetic biology combined with sustainable manufacturing.

What Are the Biggest Challenges?

Several major challenges remain.

Safety

Researchers must demonstrate that every ingredient produced by the microbial system is safe for human consumption.

Taste

A food system must be more than technically edible. People have to be willing to eat it.

Formal taste testing has not yet begun.

Cost

The technology must eventually compete with conventional food-production systems.

Scale

Producing a small prototype is very different from manufacturing enough food to feed large populations.

Efficiency

Researchers need to improve how efficiently waste carbon is converted into useful food ingredients.

Regulation

Any future commercial food product would require extensive regulatory review.

These challenges mean that the technology is promising but still experimental.

A New Way to Think About Waste

The most interesting part of the project may not actually be the cookie.

It is the idea of treating waste as a resource stream.

Plastic contains carbon.

Agricultural waste contains carbon.

Food contains carbon.

The researchers are attempting to move that carbon from one form to another using chemistry and biology.

If the process can eventually be made efficient and safe, it could become part of a broader circular system in which fewer resources are thrown away.

Key Facts

• Researchers: Southern Illinois University Carbondale
• Project: µBites
• Main plastic: PET
• Biological system: Engineered yeast
• Food format: 3D-printed cookie prototypes
• NASA connection: Deep Space Food Challenge
• Potential applications: Space missions, disaster zones, submarines and resource-limited environments
• Additional compounds: Protein, fats, vitamins and flavoring molecules
• Vanilla compound: Vanillin
• Vitamin-related compound: Beta-carotene
• Human taste testing: Not yet formally conducted
• Current status: Experimental prototype

Frequently Asked Questions

Can scientists really make cookies from plastic?

Researchers have developed a prototype in which carbon derived from PET plastic and agricultural waste is processed by engineered microorganisms into food-related compounds. The resulting ingredients are incorporated into 3D-printed µBites cookies. It is not simply untreated plastic being put into a cookie.

Are the plastic cookies safe to eat?

Researchers report that available data indicate the µBites are safe to eat, but formal human taste testing has not yet begun because the team is awaiting institutional approval.

What are µBites?

µBites, pronounced “microbites,” are experimental protein-rich cookie prototypes produced from ingredients generated through microbial processing of plastic and agricultural waste.

Why is NASA involved?

The research was developed as part of NASA’s Deep Space Food Challenge, which sought technologies for producing food in resource-limited environments during long-duration space missions.

Can plastic really become protein?

Plastic itself is not directly transformed into protein. PET is first broken down into smaller molecules, and engineered microorganisms then use those carbon-containing compounds to produce new biological materials, including proteins and other food-related compounds.

Could this technology help solve plastic pollution?

It could eventually provide another way to upcycle some plastic waste, but the current technology is still experimental. It is too early to say that it can solve the global plastic pollution problem.

Could astronauts eat these cookies on Mars?

That is one possible future application, but the current µBites are only a prototype. The technology would require substantial development, safety testing, scaling and regulatory approval before it could become part of a real space food system.

The Bigger Picture

A cookie made from plastic sounds like science fiction.

But the science behind the µBites project is based on a simple idea: waste contains valuable atoms that can potentially be reused.

Researchers at Southern Illinois University Carbondale are combining chemical processing, engineered microorganisms and 3D food printing to explore whether discarded materials can become useful food ingredients.

The project began with a problem faced by future space explorers — how to produce food while carrying as little waste and external supplies as possible.

But the same principle could eventually have applications on Earth.

If scientists can improve the technology, microbial systems could potentially turn waste streams into useful resources in places where conventional food production is difficult.

For now, however, the plastic-derived cookie remains an experimental prototype.

The next major test is not whether scientists can print it.

It is whether they can make the system safe, nutritious, affordable, scalable — and something people actually want to eat.

Sources & References

Primary source: American Chemical Society — This Cookie Started Its Life as a Plastic Bottle.

Additional source: American Chemical Society — Chemists Transform Plastic Into Space Food.

Research institution: Southern Illinois University Carbondale.

NASA connection: NASA Deep Space Food Challenge.

Editorial note: The µBites project is an experimental prototype. The technology does not mean that untreated plastic is edible, and formal human taste testing has not yet begun. Claims about future use on the Moon or Mars remain potential applications rather than demonstrated capabilities.