What’s the difference between compostable bags and biodegradable plastic bags, and which option is better for the environment?

With the spotlight continually being shone on the impact of plastics on the environment worldwide and with Australia’s Eastern States finally implementing a Plastic Bag Ban, let’s take a look at one of the alternatives…. compostable plastic bags.

Today I’m joined by Darren McAllister, from BioBag Australia to chat about compostable bags, how they differ from biodegradable bags and how Biobag is championing this area.

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1. How did Biobag come about? Who thought that it would be a good idea to make a plastic bag replacement from corn?

It’s an amazing invention, and it’s really actually hard to find out how it actually came about because BioBag’s a privately-owned company, and it’s still run by the guys that came up with the initiative back in 2003 when they switched totally to a cornstarch-based material.

Before that, they were just basically a polyethylene-plastic company (founded around 1959) and then, in 1993 they pioneered bioproduction in Norway. In 2003, they switched to be 100% bio-packaging.

They expanded in strength after that; in  2005, a new plant in Belgium; 2007, in the USA; and later this year we’ll have a plant here in Australia as well. So, they’re just expanding around the world with this amazing material and packaging.

2. What’s the difference between a compostable bag and a biodegradable plastic bag?

There’s conception around the place that a biodegradable bag is a good thing. But a biodegradable bag is just a plastic bag that has been made so that it breaks down into tiny pieces over its time, and that happens through sunlight and oxygen and that sort of thing. So, a strong biodegradable plastic bag that you’d buy today, in five, ten years would just be flakes, essential microplastics.

Microplastics are really dangerous for our environment, and scientists are finding microplastics now in mussels and fish, in water, all around the planet. So, it’s really getting very dangerous for the environment. Any anything that you see with biodegradable or degradable on it, and it might have a pretty picture of the Earth on the bag as well, it’s still a plastic bag.

On the other hand, Biobag bags are compostable which means they break down into nothing. They’re made of cornstarch, and that just goes into the soil or into the compost or into the worm farm or into the landfill, and over time just disappears. Compostabel bags are much better for the environment than biodegradable bags.

Cornstarch is a strong product. There’s a bit of perception around the place that it might be a slightly weaker product. It’s probably never going to be as strong as the thick plastic bags that you see around on the shelves, but it’s still a very strong product.

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3. How long does it take for a BioBag compostable bag to compost?

At the end of the day, once you’ve used a bag as a bin liner or a food-seal bag or dog poo bag or whatever application, once you put it in the ground … in a commercial composting scenario, it takes about four to five weeks. A commercial compost is kept at the right temperatures over time. It’s stirred. It’s looked after. It’s nurtured. So, that’s why there’s quite a quick breakdown period for our material.

In a home compost, you’re talking maybe 10 or 12 weeks depending on how good your compost bin is, and then in landfill or other areas, obviously, it’ll take longer depending on what’s lying around the material.

4. Do you find most households compost their bags and food scraps in their own composing bins or is more common to use a Council facility?

The councils certainly are big users of our bags, and through that then the consumers provide the food scraps from the kitchen caddy or whatever back through their green bin, and then they send it off to be composted. So, that is probably where BioBag has been traditionally fairly strong over the last few years in Australia, but we’re seeing more and more domestic sales where people are using them across the board to replace plastic for applications like lining rubbish bins.

It’s a growing market for us, and different businesses online, eco-stores like Sustainahome, are really helping grow that market. We’re still a fairly young company in Australian terms, and we’re really only just scratching the surface as a market. We’re only just now getting into some retail stores around Australia, so people can buy them off the shelf. We’ve got a few distributors around the place promoting us as well, so that helps. There are two separate markets with the councils and retail, and it’s a growth phase for us.

5. Take us through some of BioBags compostable products and how they work.

Our biggest seller at the moment is our 8L caddy bag. The way this bag works is that you have a kitchen caddy which is like a large lunchbox, if you like, that sits on your kitchen counter, and you line that with our 8L bag. As you’re chopping up your veggies and your peels and lots of stuff, those scraps go into there. You can also add tissues or anything that can be a compostable, anything paper-like, and then that usually then goes into the green bin for your council, or people put them in their composting bin or their worm farm.

Most people use these in the kitchen, but we also have a butcher who uses these 8L bags to package his meat products instead of plastic. I was also just talking to a florist yesterday who is looking to use our bags as a base for her flowers instead of using plastic. So people are coming up with different ideas on how to use these small bags.

Another popular product of ours is the resealable food bag. That’s sort of a replacement for the traditional Zip-lock bag.

This is a fantastic product. Again, 100% compostable, even the zip across the top, and it’s being promoted mainly through the schools with some research back from KESAB (Keep South Australia Beautiful), KESAB. They do audits through the schools, and the largest item that they find in the rubbish bins in schools is Zip-lock plastic bags.

Biobag Compostable Resealable Food Bag

Biobag Compostable Resealable (Zip-lock) Bag



The other most popular product we have is the dog poo collection bags.


Are these are the ones that are purchased by councils, or do people just buy their own doggy bags? I know a lot of people that just steal… is that the word?




Take from the Council supply?


Yeah, something like that!

At the moment, it’s our largest seller online. There’s not a lot that we sell through the councils. They buy these black plastic bags on a role, they’re made in China, and they make trillions of them at a time, and the price is like a third of our price for our product just because there’s millions and millions of them sold around Australia. We’re talking to councils about switching over to a compostable product, and on the environmental level, they are so keen. They really would like to do that, but it’s the financial cost because people do “borrow” them quite often.

So, from that point of view, it really has to be a legislation thing, I think, for the councils going down the track because they’re not really going to go back to the counsellors and say, “We need to triple our investment in dog bags to look after the environment.” It’s not really going to sway, and that’s what they’ve told me, so it’s about putting pressure on local councils by us as people that live in the councils, and demanding that they invest in a different product, whether that’s ours or someone else’s. It’s got to be a consumer-driven change from that point of view because it just financially doesn’t stack up for them right now.


I think we’ll get there. I know there’s a lot of talk in government, and I only saw a Sydney Morning Herald article yesterday pushing for an Australian-wide ban on single-use plastic, so if some of these areas start to get legislated, obviously, we’re going to see a lot of change happening. Of course, legislation changes take a long time.


I was at a seminar yesterday in Adelaide City with our minister for environment and water, and he did a presentation on where South Australia is that in the scheme of things of waste management, and we divert about 85% of our waste through to recycling or compost, and we’re well ahead of the rest of the country, which is really encouraging and exciting. But one of the things he touched on was about the changing collection patterns and times for rubbish to encourage people to put less in their red bin and more in their green bin. So, go green bin once a week, and red bin fortnightly instead of the way it is, so reversing it. Then through that, teaching people that a red bin’s bad, and the green stuff’s one we want more of sort of thing. So at government level, thinking about how to do things slightly different as well, so it was really encouraging as well.

Laura:    Well, they got the colours right because red’s a danger colour. In nature you have creatures like the red-bellied black snake and red-backed spider, so when you see them you think “Stop. Red,” whereas green is go.


Yeah, that’s good. I actually hadn’t thought of that. It’s sort of interesting.

The final product I wanted to highlight, which is really an unusual one, is a toilet bag.

We have this little toilet seat, a freestanding toilet seat that you can buy, and then there’s one of our bags that lines it. So, if you’re out camping or something like that out in the bush, you can do your business and discreetly tie the bag off and bury it somewhere.


We should just say for our listeners outside Australia, bush is basically our outdoors. Like, we go out into the forest or the desert or up into the mountains, that’s just what we call the bush, so it’s not like we’re just going into a hedge on the side of the road!

And often when you are out in the bush, toilets can be several hundred kilometres away. I mean, Australia’s a massive country, and, yeah, there might just be roadhouses that are a few hundred kilometres spaced apart if you go inland, where like the area I’ve lived the last 13 years. So I imagine if you’re living in London they may not be practical, but when you’re living in a remote area or you’re camping you’re going to need them. I just wanted to clear that up as well.


Yeah, it’s an interesting little product that we just sell bits and pieces of from time to time, so it just bubbles along. It’s another unique BioBag product.

6. In some cases, greener waste options still have an environmental impact. Can you share what the biggest impact of making or distributing the compostable bags is and how BioBag Australia is addressing this?

This is a tough question, but it’s an interesting question because it’s something that comes up often with our customers and supporters who say, “What is the environment impact of manufacturing and distributing your product?”

So, from the manufacturing point of view, we do use resources like power and water and those sorts of things, and I guess there’s no way around that at this point in time because in a perfect world we wouldn’t need that, but we need these resources to melt it the raw material down, extrude it, and then convert it to bags.

At our plant here in Adelaide, our roof is completely covered with solar and has been for six or eight months, and that’s had a big impact across the manufacturing that goes on in our plant. From the point of view of transportation, that’s where BioBag Australia is looking at manufacturing the product here, to reduce that footprint.

At the moment, we source our bags from Belgium and Norway, and obviously with that, they’ve got to travel via ship, so there’s obviously the impact on the environment through that. So, we will be making them locally from September. We’ll still need to source the raw material from Europe, but down the track there may be an opportunity to source it locally, but at this point in time there’s only one manufacturer in the world that we’re aware of that can make the product that we need.

We’re certainly conscious as a business of the environment impact that we have, we think about things that we touch from a business: paper, toilet paper, power, cardboard, and we recycle as much as possible.

7. Where to next for BioBag?

Apart from setting up production locally in Adelaide we’re looking to expand more into the retail market in Australia and New Zealand. We’re approaching lots of businesses, making them aware that we’re here. The conversations are coming through these larger companies from the consumers, which is real exciting.

For example, Foodland’s customers in Adelaide asked them for compostables, so when we went and talked to them, the conversation was quite an easy one as opposed to being a hard-sell, and we’re finding that across most businesses.

Some of the big guys have been a little bit more challenging, and then other companies that I’ve reached out to, it’s just not on their radar at this point in time, so I guess that’s where we encourage consumers to let their pet shop or their shopping centre or where they buy their goods from to let them know they want to pitch these products through there. So, that’s sort of the future for us, and then of course when we start making the product here, it’ll just continue to grow.


Well, I wish you all the very best in your endeavours with BioBag and taking the company ahead in leaps and bounds in Australia and beyond. Thank you very, very much for coming on Eco-Chat today.


Thanks, Laura. Thanks for having me. It’s been fun. Loved it.

To Learn More About Biobag Australia click HERE to visit their website.

A selection of Biobag products are also available online at Sustainahome.

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