Plastic-Derived Cookies: From Pollution to Nutrition

Human Transcribed

Dr. Lahiru Jayakody:

I think this is going to be a huge impact. Think about spacecraft. You saw the Artemis mission. They open up all the plastic stuff, right? Now, that's a resource freely for that mission scenario. You can able to use that plastic in making some food to eat.

Sandhya Jayasekara:

This is something unconventional. So I think our responsibility lies on trying to educate the society on these new concepts. We have to send out the correct message on what we are doing and how it's going to affect the future.

Chai Nussbaumer:

Turning plastic into food might sound unconventional, but it's just a matter of careful science.

Micah Schweizer:

Our guests have harnessed natural processes to create a new plastic derived cookie.

Chai Nussbaumer:

Which could help solve two of the world's biggest problems.

Micah Schweizer:

In this episode, we'll find out how these cookies are made and how the public and media have responded to the project.

Chai Nussbaumer:

I'm Chai Nussbaumer.

Micah Schweizer:

And I'm Micah Schweizer. This is Balancing the Future from METTLER TOLEDO.

Chai Nussbaumer:

On this show, we explore the world of science and technology, and the solutions transforming our lives.

Dr. Lahiru Jayakody:

I'm Lahiru Jayakody, associate professor at Southern Illinois University Carbondale.

Sandhya Jayasekara:

I'm Sandhya Jayasekara. I'm a graduate research assistant at the Southern Illinois University Carbondale.

Micah Schweizer:

So what you've done is develop a technique for upcycling plastic into a food ingredient, and you've created what we're calling plastic derived cookies. Can I ask, what was the inspiration for turning plastic into a food ingredient?

Dr. Lahiru Jayakody:

Yeah, so my team actually looking in the way how we can tackle the plastic problem, the way we thought we need to have a more high value products from plastic to get traction from the market, right? So in that case, we are trying to do what called upcycling rather than recycling. So we working on making chemicals and other high value ingredients. And then we thought, why not food? Because we eat, we drink, and we breathe plastic, microplastic. So how we can break that. If you take the food cycle, it's a carbon cycle. You take carbon, hydrogen, nitrogen, sulfur, all that stuff in your food. So plastic has it, why not? So we had a great opportunity with NASA Deep Space Food Challenge. That's actually the trigger factor to think about why not plastic to a food. The other side of the coin is we need to produce food in different way because the challenges we have with the current agricultural system, they're not sufficient enough to feed population in future.

Micah Schweizer:

How did project funding from NASA come about?

Dr. Lahiru Jayakody:

Yeah, so the NASA had this program. They want to send astronaut to Mars, three-year mission, spacecraft, tiny place, and then you go to the Mars or the lunar surface. Imagine you have a resource limited situation. So you need to think about reinventing the food production system to survive in that situation. So they have this challenge, and we luckily got funding from NASA to do this work.

Micah Schweizer:

Can you describe to people listening what one of these cookies actually looks like?

Sandhya Jayasekara:

We have 3D printed the cookie in different forms. We can decide what shape it comes in, so the texture and the smell of the cookie. So at the moment it has a pleasant smell and a texture that you can feel like a general cookie.

Micah Schweizer:

Okay. So you've smelled it, you've broken it, you have not yet tasted it, however. I have to say, we've talked to other people who are working with food in unconventional ways or in novel ways, and this is a recurring theme that they develop something and they haven't yet tasted it. Is this frustrating to you?

Sandhya Jayasekara:

When we are developing a food, first, I don't think first thing is the tasting. It should be a sequential process that we reach to tasting. Before that, there are several experiments tests that we have to follow. I think we are very close to go to the tasting level after completing the current experiments that we are doing. So I don't think we have to be frustrated about it. If you are following the process correctly, then we can reach to the point that we can finally taste our cookie.

Micah Schweizer:

And it does sound like you are very process oriented on this. Walk us through the steps of sort of arriving at this cookie.

Dr. Lahiru Jayakody:

So we have a 32 step process here.

Sandhya Jayasekara:

Process begins with the integration of this plastic waste. As the start, we have used polyethylene terephthalate, which is the PET bottles. Then as the plant biomass, corn stalks. So then in that initial process, we break down them using high temperature pressure into those substrates. Then we actually get a liquidized form of those substrates, and that liquid form we are using as a culture medium for the growth of yeast. And then they grow in that culture medium and then they produce a slurry, which includes proteins lipids, vitamins and all these ingredients. Then we use that slurry in our 3D printer to print the cookie.

Micah Schweizer:

Lahiru, can you tell us a bit about the yeast that's involved in this process?

Dr. Lahiru Jayakody:

We use yeast as a genetically safe organism, and that's the key for us to select that organism. Not only one type of yeast, we are selecting different type of yeast for this, and we changing their genetic profile. Now, you or I cannot eat plastic or the grass. True, right? I get this analogy all the time. So cow can eat grass because they have microbes inside. These are like a tiny organism. So the chemistry running through the system in the tiny organism, we can actually do this in microbes like we are seeing in a macroorganism like cow, right? So the way it's working in the bioreactor, you're putting the input and output. So yeast is a good organism because we've been using that. We have all the tools safely changing their metabolic profiling, the way we needed to eat this unconventional thing, right? So we're tailoring the microbes to eat that and provide something that we can use at a back end like protein.

Micah Schweizer:

So you're saying in the case of a cow, grass in, milk out.

Dr. Lahiru Jayakody:

Yeah.

Micah Schweizer:

And in the case of this yeast, it's plastic slurry in and cookie out?

Dr. Lahiru Jayakody:

I would correct it, it's plastic derived chemical. Because people are getting confused in this fact because everyone know about microplastic and they're concerned about it. So please note that this cookie doesn't have microplastics like your milk. You don't have a grass particle in your milk, do you?

Micah Schweizer:

I know, you don't see that.

Dr. Lahiru Jayakody:

No, that's the same thing. So that's why we call this, what we call the concept is biofunneling. You take these different material and you put into a biological system to do the chemistry and getting out the product that we need it.

Micah Schweizer:

And how long does it take to break down the plastic?

Dr. Lahiru Jayakody:

It would take like 10, 15 seconds in these reactors to get somewhere around 70 to 80% of carbon into the liquid slurry. And then we use the enzymes to get that converted and then next step is feeding that into the yeast. Currently, we are looking in, depend on what type of biomass we are feeding or the plastic we're feeding. So it take 24, 48 hours to grow them and to produce enough compounds. And our target is reducing that gap. That's the research and development we need to do make it. Now, if I say we are not waiting like 400 years. If you put a plastic bottle to the outside, it's like that level to get into microplastic, but we now have the process to break down. It's more intense.

Micah Schweizer:

Sandhya, are there any byproducts from the process?

Sandhya Jayasekara:

85 to 90% of whatever the substrate we are using is broken down into that slurry. There may be some byproducts coming out after the yeast is grown. The important thing is whatever the end products that we are not using, we can feed back into this cycle as the substrate and let the yeast again utilize it and again, give us the important material at the end. There are some byproducts that we are not using at the moment, but we can recycle it through this same process.

Micah Schweizer:

Okay. So the waste product goes back into some step of the process, which then further reduces the waste stream.

Sandhya Jayasekara:

Yeah.

Micah Schweizer:

Amazing.

Dr. Lahiru Jayakody:

Yeah. We could also able to recycle some of the water. So that's the other important point. So if you take water because our system is using water back. And the waste design to fit into a spacecraft, you can imagine the limitation in there, right? So we need to think about energy, we need to think about waste, we need to think about the water. So we design the system in a way, have a less waste. Idea is zero concept, zero waste, not there, but we have like a 10, 15% of carbon waste right now. We want to get it reduced. That's how you're going to push your limits and make it economically viable.

Chai Nussbaumer:

Hey, Micah.

Micah Schweizer:

Hey, Chai.

Chai Nussbaumer:

Micah, did you know that in 2025, scientists at the University of Edinburgh managed to turn the same PET bottles used for these cookies into paracetamol?

Micah Schweizer:

That's amazing. How did they pull that off?

Chai Nussbaumer:

Well, they used a fermentation process and it's a lot like brewing beer. The scientists reprogrammed a harmless version of E. Coli bacteria to convert terephthalic acid into the main ingredient in paracetamol.

Micah Schweizer:

So does this mean they're basically upcycling PET bottles into medicine?

Chai Nussbaumer:

Exactly. The research was an out of the box or out of the bottle way to tackle both plastic waste, and the use of fossil fuel-based materials in paracetamol production.

Micah Schweizer:

Have you done any calculation on sort of what one cookie or a package of these cookies would cost?

Dr. Lahiru Jayakody:

We did a preliminary technoeconomic analysis based on the laboratories. Now, we call this manufacturing readiness level three. So we had to go like seven scale to get it ready to the market. Now with that three level, what we're looking in a kilogram of this protein going to be $60. So that's within the margin. It's a different type of protein we have market. Now, as I said to you, we already identified some of the biggest cost barriers for us. So if you tune this system and if you go to a scale, we think we could able to bring down the cost substantially to compete with other ingredient. But most importantly, yes, the protein market is one of the target, but it's not the main thing. You're trying to tackle plastic pollution in this system, and that should have some advanced effect to the total concept.

Micah Schweizer:

You mentioned earlier, of course, that this is one ingredient in the efforts against plastic pollution to reduce it and to limit it. How much of an impact do you think this approach could have if it's scaled up to the degree that you're envisioning?

Dr. Lahiru Jayakody:

If you're able to get into the scale, I think this is going to be a huge impact. Now, if you take the plastic market, most of the plastic, bigger portion of plastic going to the packaging industry. So what other group and the other researcher are trying to develop a biodegradable version of this material, right? So our idea is, okay, if you have food grade material, biodegradable material, we use in food packaging, and then you take that back into our system and producing protein. You know what I mean? I'm not talking about going into a landfill and collecting all that plastic and producing food. That's not the idea because those plastic containing other attitudes, other toxic hazards already, that's all we know. So if I want to produce that, that's another 10, 20 years of research I have to do a biofunneling to take out all this stuff, right? So it is not impossible theoretically, but that's not the target. So our target is, hey, let's go to develop this cycle. We call it circular economy, really.

Micah Schweizer:

So I go to the store, I buy say a package of conventional cookie dough cookies. I take the package back and the next time I could buy cookies that have been made from the package from my first purchase.

Dr. Lahiru Jayakody:

Yeah, that's the real deal. Think about spacecraft, right? You saw the Artemis mission. They open up all the plastic stuff, right? That's how we are dealing with now. That's the resource freely for that mission scenario. You can able to use that plastic and making some food to eat.

Micah Schweizer:

The fact that we're talking here today is sort of a testament to the attention that your research is getting. What kind of reactions have you been getting?

Dr. Lahiru Jayakody:

So I'm academics, part of my job is educating my society, right? So this is wonderful tool that I never imagined have a power. Actually, it's have a power to disseminate the idea about plastic pollution and also what we can do with that. So it's a tool for me. And if you see now after these all media campaigning, some of the things I'm seeing in the social media, it's super crazy. That's how we are thinking this problem, right? People who know the idea about this basic technology has less concern. People don't know about anything on this and just know about plastic and microplastic, they have a lot of issue. They think I'm going to feed you microplastic. Never, never. That's not the idea, right? So the microbiotic process is to control the microplastic, I would put in that way. This is a really good learning curve for us.

A lot of learning. We are academics, we're doing research in the labs. Most of the things are staying in the lab forever, not going into the market. But we are now looking into translational research, so this is something we want to get into the society. And it's need what I call the marketing strategy. I am personally learning how to market this. We never think about that part as a classic professor in a university. So we now have a role to think about this different aspect, and I'm learning that. Thanks to ACS putting together this amazing video that's trigger all the flames right now we've seen.

Micah Schweizer:

You mentioned the ACS who produced the video, that's the American Chemical Society?

Sandhya Jayasekara:

Yeah.

Micah Schweizer:

And you're smiling as Lahiru talks, Sandhya.

Sandhya Jayasekara:

We didn't expect at the beginning. I just was submitting an abstract to ACS, and they just reached out to us telling that, okay, you have a great research. Interesting. It's worthy of doing a video. So that's where we started this. And then a lot of media traction, and then we learned a lot of things how to respond to these different ideas coming from different platforms. This is something unconventional, so definitely there should be some teaching and learning process going on about all this. So yeah, that's a great opportunity that I received, especially as a PhD student. I think our responsibility lies on where we are trying to teach or educate the society on these new concepts. We have to send out the correct message on what we are doing and how it's going to affect the future or the society.

And we have to confirm as well that we are not trying to do anything wrong to the society. We are just exploring our science and we come up with some inventions, and then we are bound with the responsibility to communicate the correct message to the society. So that's we are trying to do at the moment.

Micah Schweizer:

And so what's next? Where are you trying to take your research next?

Dr. Lahiru Jayakody:

Yes. As you said, this has a good traction and we need support. So I'm trying to build up that support because everything is based on how much support I'm getting from the community, from the funding agency to the commercial partners. Right now we have infancy technology, I would say like that, proof of concept. So we have several steps to go. So many things die in the lab. These technologies, I really wanted to get into the society, translate it. So I see the traction, that's why you reach to us, you see some good positive advantages of this technology. So next few years, we are very open for collaborating with other researchers, industry, funding agency, foundations. If we have correct support and we could able to develop this technology to get into the society, which we are planning to do.

Micah Schweizer:

And Sandhya, for your research, for the PhD work that you're doing, where are you taking this next?

Sandhya Jayasekara:

So currently, we are at the level of conducting some studies to confirm that this product is safe to eat. So currently, we are focusing on conducting several experiments, including studying the allergic effects of this cookie and the digestibility of this cookie. Likewise, there are several experimental aspects that we are currently working on to confirm that the cookie is safe to eat. So currently, we are at that level.

Dr. Lahiru Jayakody:

Yeah. At the end of the day, she need to write a thesis to get the PhD. That's a classic way of student thinking, come to a lab, get your PhD, the letters. So I'm asking my student not to do that. Do a work that have a real impact. So this is one of the examples. So you could able to part of a very impactful research. And it's not only earning you a thesis, but it gave you some important motivation why you need to be a scientist in the future.

Micah Schweizer:

Well, I wish you all success with it and look forward to hearing how it tastes when you're finally at that point. Thank you so much.

Dr. Lahiru Jayakody:

Do you want to eat it?

Micah Schweizer:

I'd love to try it too.

Dr. Lahiru Jayakody:

Yeah.

Micah Schweizer:

Yes, I would try it.

Dr. Lahiru Jayakody:

Great.

Micah Schweizer:

Yeah, of course.

Dr. Lahiru Jayakody:

Wonderful. Thanks for having us.

Sandhya Jayasekara:

Thank you.

Micah Schweizer:

Thank you so much. It was a pleasure.

Chai Nussbaumer:

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Micah Schweizer:

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Chai Nussbaumer:

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