Red To Green Talks: Biodegradable, Compostable or Recyclable Packaging? Differences and Misconceptions

In this very special series, we are sharing excerpts from Season 2 of the excellent Red to Green Podcast created by host and future food enthusiast Marina Schmidt. The show features in-depth conversations about the intersection of the food tech industry and sustainability. Season 2, titled ‘Plastic Alternatives’, is dedicated to the world of food packaging with a focus on exploring alternatives to fossil fuel plastics and solutions.

The confusion of solutions

The below conversation is an excerpt from Red To Green Season 2, Episode 2: Bio-degradable, Compostable, or Recyclable? The Differences and Misconceptions. In this episode, Marina Schmidt, founder of Red to Green Solutions talks to Julia Goldstein the author of the book, Material Value which was a finalist in the 2019 San Francisco writers contest.

Audio transcript by Descript, with edits by Anya Roschke.

Julia: Yes. It’s interesting because for example, companies that say, okay, we have zero waste to landfill. There’s a number of ways of achieving that. And part of it can be some burning waste for energy. And I think that should probably be more of a last resort. The first way should just be to use less, to begin with, reduce your incoming resources and make your processes less wasteful, but there can still be value in converting it to energy. If it’s done safely versus just putting it into a landfill.

Marina: Yeah. There are so many ways of putting things, concepts in a way that sounds good in that field, but actually, if you look deeper into it, it turns out that it’s far from a good solution. Let’s start going through all of these confusing words and definitions used within that context. So, does plastic actually biodegrade? Because there’s the difference between something just degrading and biodegrading.

What is the difference between degrading and biodegrading?

Marina: What is that kind of difference?

Julia: It depends on the type of plastic, but most of the conventional plastics that everybody is familiar with do not biodegrade. For something to be biodegradable, it needs to degrade into simple compounds and elements, for example, water and carbon dioxide. If it breaks down to that level, then it’s biodegradable.

But if it just breaks into tiny pieces, which is what happens. When you have plastic bags and just set them out into the sun, they’re going to start breaking into little pieces.

“Most of the conventional plastics that everybody is familiar with do not biodegrade.”

Julia Goldstein

And what are oxo degradable plastics?

Marina: Yeah. And interestingly there are these Oxo degradable plastics, or sometimes they’re also called Oxo-biodegradable, which actually degrade by being exposed to air. Right?

Julia: Yeah. And there was a while back a movement toward creating plastics that would do that more rapidly with the idea that, okay, that was going to be helpful because they could break down more quickly.

But the problem there was if you mixed those with other types of plastics, then you’ve got a mess for the recycling situation where you’re contaminating a batch with a different type of plastic, and you’re really causing more problems than you’re solving. So I know Europe a number of years back, not that long ago said, okay, we really don’t want these Oxo degradable plastics. This is not the right way to go.

Marina: Yeah, it’s just speeding up the process in which it degrades. And with Oxo degradable plastics, you would still have the issue with the Marine and environment, with birds, and so on consuming the plastics.

Marine safe plastics

Julia: Absolutely. At some point, I talked about an ideal plastic that would be not only recyclable but would also degrade and would be Marine safe, right? It would be marine degradable. It would degrade in a marine environment down to safe, simple compounds, not tiny bits of plastic that all the marine animals are going to ingest.

For example, plastics made from shrimp or lobster shells, and there’s a protein, the chitin protein that can be made into plastics. It’s not really quite done on a large scale, industrial level right now, but those, if they got into the ocean, could biodegrade safely.

Marina: Oh fascinating.

“To be industrially compostable, a material has to break down to fragments of a certain size within a certain time period, generally six months.”

Julia Goldstein

What is the difference between industrial compostability and home compostability?

Marina: So what about compostable? There is industrial compostability and then there’s home compostability.

Julia: Yes. And it is an important distinction. To be industrially compostable, a material has to break down to fragments of a certain size within a certain time period, generally six months. Although there are some composting facilities that’ll create compost in about eight weeks, it’s also got to be nontoxic.

You can’t have heavy metals in there. There are very strict requirements. You don’t want lead, cadmium, those kinds of toxic things in the compost. But industrial composting facilities grind everything up so they can take fairly large pieces. For example in mine, where I live, our curbside yard waste takes all kinds of stuff, food waste, compostable packaging, and branches, and leaves. And branches just need to be less than four inches in diameter.

I mean, that’s fairly large, but they can grind them all up. They heat them at a high temperature, they control the water content. They control the temperature and humidity very precisely. And they receive such a large mass of stuff that they can get the mix they need. 

But, if you compost at home, you don’t have that scale. You probably don’t have a grinding machine that is going to grind up everything into small pieces. So, it’s going to take a lot longer to break down. Now it will break down, but if it’s not going to break down fast enough, you’re not really going to be able to have the compost. And then there’s also the issue of the right amount of green matter and Brown matter, right?

Green [matter] is more like the Apple cores recently fallen: leaves, grass, trimmings. And the Brown is like the Brown leaves. You can even use shredded paper, that kind of thing. And so you’ve got to have the right balance and you have to have the right amount of water in it. So people do home composting, but you can’t just toss in anything and assume you’re going to get good compost.

“San Francisco incentivizes citizens to do industrial composting because they have to pay more for putting things into black bins.”

Marina Schmidt

Marina: Yeah, and it takes a certain dedication to do compost, to actually also have the space to be able to do it. I’m not sure if you would want to have that inside the house. Actually, if you even find the space to have it inside of an apartment.

I saw a documentary today where it was mentioned San Francisco incentivizes citizens to do industrial composting because they have to pay more for putting things into black bins. Whereas they pay less if they put things into the composting and the blue recycling bin so that I found quite interesting and they seem to have quite a bit of success with actually picking up the trash and creating good compost, which is used on local farms, et cetera. 

How often do you already put plastic, like compostable materials in there?

Plastic and composting

“It’s everybody’s responsibility to put the right stuff in the right place.”

Julia Goldstein

Julia: I don’t tend to have those except for the bags of course. So, my little three-gallon container, I line with a compostable bag and those are actually made from agricultural materials like corn stalks and things like that. So those are the main source of it. I don’t tend to have a lot of those compostable plastics but I can tell you that a lot of people put stuff that doesn’t belong.

I went to Cedar Grove, which is the name of the company that does our industrial composting. They have a facility where you can go and you can pick up a whole truckload of compost or mulch to use in your garden. I did this and I looked at it. At one point, there was a piece of those stickers that we have on fruit and a little piece of a plastic straw and something that looked like it was one styrofoam and these were all in my compost. So they try to screen out contaminants like that, but obviously, they don’t do it a hundred per cent.

Part of the message is that it’s everybody’s responsibility to put the right stuff in the right place.

“But taking a compostable plastic fork and putting it in there. Yes. If they chop it all up, it will degrade and it’ll degrade into pretty much carbon dioxide.”

Julia Goldstein

Is the availability of composting different in different countries?

Marina: In Germany, as far as I’ve been living in Berlin, I have never had a composting bin here, in terms of it being provided by the landlords. This is shocking because Germany prides itself to be so big on recycling. It would be really interesting to me to look into the future. What if we would replace the recycling facilities with industrial composting facilities and replace all of them let’s say non-compostable plastic with compostable options? How would these two different scenarios measure up?

Julia: Well, I do believe that expanding composting is really a good thing in the United States. I read that only 2% of communities in this country have access to this kind of curbside composting of food waste that we have here in Seattle. Most people don’t have it, but it could certainly be added, but yes, you need to build more composting facilities.

I wouldn’t say to just get rid of the recycling facilities, because it’s not going to be easy to just get rid of conventional plastics. And there are also issues in large-scale switching over to bioplastic alternatives because those are made from plants. And the question is, do you have acres and acres of crops that now you’re growing to make plastics?

Marina: Hmm.

Julia: Ideally those would say, come from agricultural waste, which to some degree they do, especially if you think about the fiberboard boxes that replace styrofoam, like if you get a takeout meal and it looks kind of like cardboard, but it’s not, it’s a fibre that’s made from say the wheat stocks.

There are trade-offs, right? If you just, suddenly, on a large scale, make a shift, it’s not necessarily going to go as smoothly. And just thinking that as long as you’ve got compostable plastics, all is well. They don’t contribute to the nutrient value of the compost. If you put in food scraps and leaves and branches, those have value. Those have nutrients that help make the compost healthy for growing plants and vegetables. But taking a compostable plastic fork and putting it in there. Yes. If they chop it all up, it will degrade and it’ll degrade into pretty much carbon dioxide.

That’s not really helping the compost. And so some cities here don’t take those, like in Portland, Oregon, they don’t accept those kinds of plastics into the compost.

“I think providing all the food in compostable containers and with compostable serving ware is a great solution.”

Julia Goldstein

So, what is the way forward?

Marina: But, I mean, that’s also a question of priorities and that scenario, getting good compost and getting good soil seems to be the priority. But then if an industrial facility has the priority of replacing plastics as good as possible and therefore composting the alternative products, even though the soil may not be as good, that could still be a good option.

Julia: Yes. And I think, especially in places where you’ve got food service too, a lot of people and well, someday we’ll have large outdoor events, again, like, music festivals or sporting events. And there, if all the food comes in compostable packaging, then it can all be dumped into one bin at the end and taken for composting because of the idea that, oh, then people have to separate out.

And if it’s recyclable, then it is contaminated with food, which is a mess for the recycling system for those kinds of things. I think providing all the food in compostable containers and with compostable serving ware is a great solution.

Marina: Yeah, but it seems to me like plastics is definitely not the way forward. and therefore there needs to be some good alternative solution. And as you described in your book, plastics are not such a novel technology they’ve been created in the forties, fifties, and so on mostly. So, there could be such an opportunity to have new innovations, which are actually now cutting edge, replacing something that we’ve been using for many, many decades.

So what is the path that you see forward towards a more sustainable food packaging solution?

Julia: I think there’s a mix of things. Sometimes the best packaging is no packaging at all. For example, if you buy a bunch of bananas in the store, do you need to put them in a plastic bag? They’re already in their own packaging, the banana peel, but plastics do have a benefit in keeping things fresh. For example, carrots, if you just put them by themselves in the fridge, they quickly become all limp, they don’t even last a week, but if you put them in a plastic bag, they will last.

I think there are probably many opportunities for businesses throughout that supply chain to minimize the amount of packaging and some of it is necessary to protect the food. Right? You’ve got this trade-off: if you don’t package things at all, you’re going to have a food waste problem because the food is going to arrive in a condition that it’s damaged or spoiled.

But there are opportunities like these plastics that are based on proteins from shrimp shells. One example is also milk-based proteins. Those can be made into a stretchable film. And I think using that for say wrapping cheese would be fantastic. A film based on milk protein that then just will dissolve in water almost. That could be really good, but you have to explain to people how to use it.

Marina: Hmm, what would happen with that? Milk-based protein film once you’re done with it, would that go into the compost.

Julia: Absolutely.

“Sometimes the best packaging is no packaging at all.”

Julia Goldstein

Are different solutions needed in different places?

Marina: But wouldn’t that be filtered out in, I don’t know where it was, San Diego? No. Where do the plastics or plastic looking materials get filtered out?

Julia: In Portland, Oregon, they don’t want to accept those. But what they’re talking about is stuff made from PLA. Polylactic acid, which is a type of bio-based plastic, meaning it’s made from plants often corn wheat, sugar cane, but it looks like a conventional plastic and it will technically biodegrade. But not easily. That is the specific type of bioplastic or compostable plastic that Portland says we don’t want. But something like this film, based on a milk protein, should be absolutely compostable. And I would think it should be accepted everywhere but it’s not in common use yet. 

Marina: That’s very interesting. Good that we clarified this because PLA, at least in my head, is just one way of having a compostable plastic alternative. But then you have all of the other variations that are being developed right now. Various companies working on waste-based solutions, but also we may have, I have some other companies that use other feedstocks. So it’s really good to know Portland has not said, well, anything that looks like plastic or anything that is called industrially composted we are not allowing, but they’re just not allowing PLA specifically.

“Part of the problem is labelling because I don’t want to have to take out my reading glasses to figure out whether my cup is made of PLA or something else.”

Julia Goldstein 

A debate on PLA

Marina: What is your opinion on PLA?

Julia: I think it’s useful. In some cases, like I was talking about, especially for take out food and you can just take the whole thing when you’re done with it, whatever scraps are left and then put it in the compost, but for an everyday solution, I don’t know. I see it being a problem. And part of the problem is labelling because I don’t want to have to take out my reading glasses to figure out whether my cup is made of PLA or something else.

And is it compostable? Is it recyclable? I think labelling is going to be an important part, you need to make it very clear to people and there’s a natural food market in my neighbourhood. They have some new compostable packaging that is very clearly labelled it’s PLA and it says, compostable packaging do not recycle. It’s large and obvious enough that someone would see that and know, but a lot of people think they can just put it in the recycling. It’s a plastic cup, but it will contaminate the recycling. 

Marina: Yeah. I mean, it’s always tricky to do things based on behaviour change. At the top of my head, I think what could be an option is finding a way to have PLA based plastics marked in a certain way so that optical scanners are able to identify them and sort them out automatically. Do you think that is an option?

Julia: That does happen. And yes, some of the labelling happens. In fact, some of the PLA based forks and spoons have a hole in the handle. It looks kind of like the shape of a leaf, which is kind of pretty or what have you, but it serves an important function in that the sorting machines will recognize this is a compostable fork.

This does not belong in the trash. This does not belong in recycling. It belongs with the compost. The labelling, it’s often done in green ink, but you could have an optical system that will recognize that and put it in the appropriate place.

What is needed to move forward?

Marina: Hmm. Yeah. And that’s again, a topic of regulation and being able to push that forward so that all of the compostable products share a common denominator, a way that makes it relatively easy for the recycling plants to sort that out and for composting facilities to realize that this actually belongs in the compost.

I sometimes have the feeling that these opportunities are being swept aside as this is not working at the moment. But there is a lot of money flowing into recycling because clearly it’s not properly working. This is a system that would have the possibility to work well, but it will need time, energy, resources to get to the state in which it is actually a good solution.

But I could imagine once it is at that stage, it could be such a helpful contribution to moving towards a somewhat circular system.

Julia: I think so.  A lot of the problem is funding the compost facilities are having a hard time making ends meet as it is, and they don’t necessarily have the money to invest in extensive sorting systems.

“There are some naturally occurring bioplastics like natural rubber from a rubber tree, but generally we’re thinking about things that are specifically manufactured to be plastics.”

Julia Goldstein

What are bioplastics, exactly?

Marina: Well, we have already talked a bit about bioplastics. To make it official, what are bioplastics? As far as I understood, it’s both bio-based and biodegradable plastics, which are referred to as bioplastics.

Julia: Yes. Bio-based means it’s made from biomass, which are recently living organisms, not the fossil fuels that have been underground for thousands or millions of years, but plant matter and this type of thing. There are some naturally occurring bioplastics like natural rubber from a rubber tree, but generally, we’re thinking about things that are specifically manufactured to be plastics.

And then we mentioned before biodegradable, meaning it degrades into simple compounds or elements

Marina: Are there authentic samples of bio-based plastics that we haven’t touched upon yet.

Julia: I think just the fact that you can make conventional plastics like polyethene is a bio-based plastic, for example, ripening fruit releases ethylene gas, and that can be condensed and made into polyethene, which is like plastic bags. If it’s made from agriculture, then it is bio-based.

But when it’s done being processed, it’s exactly the same as a plastic bag. It’s not going to biodegrade. It’s just a matter of the source and where it comes from.

Marina: And would it be able to be recycled in the same way?

Julia: Oh, yes just like any other, no matter where the original source, whether it was natural gas, deep, underground, or a pile of rotting fruit, once it’s processed into polyethene it’s the same exact material, it’s chemically identical, regardless of the source, it can be recycled. It can’t be composted, all that, but there are also new plastics that are being created from bio-based materials.

New materials being developped

Julia: And some of the stuff is still being developed. Like you can take cellulose, which is a naturally occurring polymer from trees and make that into usable plastics.

Marina: Yeah. And cellulose is an example of a material that a lot of people aren’t aware of where it comes from. Is cellulose as you know, a good example of, um, sustainable alternative.

Julia: It could be. I think again, it’s a matter of where it’s coming from and what it takes to process it. Right? You don’t want to be, again, cutting down acres of trees to produce cellulose space plastics. Now maybe if you could make them from fast-growing plants like bamboo, I don’t know if anybody’s doing that, but you know, if you’re cutting down Oak trees to make plastic that does not to me sound like the best way to make use of resources.

Marina: So how much of an issue is the use of agricultural land? When it comes to plastics do you know how much we would actually need to make a complete switch to bioplastics?

Julia: I don’t have numbers on the top of my head, but I’d like to see a system where the default is to use agricultural waste because that already exists.

“A lot of the health issues are not the plastic itself, it’s the additives that are put into these plastics to improve their properties.”

Julia Goldstein

Plastic’s Toxicity

Marina: Let’s touch a bit on toxicity. I was very shocked to read in your book, how hard it is actually for manufacturers to evaluate the toxicity of different, let’s say ingredients and that attempts to actually create these, red lists of toxic materials have failed.

Could you elaborate a little bit about how toxic the plastic products are that we may use in contact with our food?

Julia: That can be a really difficult thing to determine. And you mentioned these different lists. I interviewed someone who said yes, he looked at a bunch of different lists and there are some things that are obviously toxic like lead cadmium. Everybody agrees, but there’s a lot of things where there are contaminants that will be listed on one list, but not another. How do you really know? And the other question is how much is allowed. There will be government regulations that say you can have a certain amount of a contaminant and then it’s safe, but is it really safe? I think a lot of the trouble is in doing the testing. I mean, it’s definitely possible in a lab to measure what different chemical compounds are in plastic, but quantifying what are the real human health risks? Because in doing studies, there are so many different variables. People are exposed to so many different things in their day to day life.

How do you know that their cancer was caused by some specific thing? That came up with these perfluorochemicals perfluorocarbons. They’re jointly known as PFS chemicals and they’re used in making stuff like Teflon. They were being released into water streams all over and there were huge, many, many years-long legal challenges. To say, can we prove that these illnesses that people had were a result of exposure to these chemicals, even though you could tell, these chemicals were present in at least 10 times larger concentrations than are supposedly safe, but can you prove that their condition was because of that and not something else?

That’s one of the difficult pieces because a lot of the health issues are not the plastic itself, it’s the additives that are put into these plastics to improve their properties. They make them flow better so they can be more easily manufactured into products. They make them fire-resistant, other types of things that are helpful but are actually dangerous to human health.

Is it possible to avoid exposure to these toxic ingredients?

Marina: Yeah. What would be some tips for individuals who want to avoid the risk of being exposed to toxic ingredients, things like not heating your plastics or not putting hot food into plastic containers.

Julia: Definitely the issue of heating is one part of it. If you think about a Teflon pan, the Teflon coating itself is inert. The big problem with the contamination was in the process used to make it, but if it’s heated to a very high temperature, it starts releasing some of those compounds.

So that’s definitely part of it, don’t heat it extensively, but sometimes you can just choose not to use that. For example, instead of a Teflon non-stick pan, you can go back to the original nonstick cast iron. Now it’s heavy, cast iron pans are dang heavy, so there are drawbacks that way and you don’t want to just let them soak in water because they’ll rust.

So there are other things you gotta take care of. And some of it may just be choosing not to use plastic to store your food in glass instead of plastic containers. 

Marina: What about aluminium or steel?

Julia: I would say stainless steel is great for things like reusable water bottles or I think a lot of us, we’re not used to metal drinking cups. I mean, that’s what people used to have long, long ago, they would drink from metal or glass containers.

I think maybe it’s just a matter of getting used to it. 

The Red to Green Podcast is available on iTunesSpotify, and all popular podcast apps by typing in “Red to Green” in the search bar. Listen to this episode of Red to Green here.

Want more? Check out the whole Red To Green Talks series here.

Lead image courtesy of Nareeta Martin (Unsplash).

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