TED Talks Daily - Sunday Pick: How a special seaweed is lowering methane emissions—one cow burp at a time | from Speed & Scale

Episode Date: April 19, 2026

Did you know that cows emit methane when they burp? Livestock account for over 12% of the world’s greenhouse gas emissions, but farmers and scientists have discovered a superfood that might be the key to lower emissions—and raise healthier cows. In this episode, Ryan and Anjali investigate the mystery of Asparagopsis, a seaweed variety that removes methane from the guts of the animals who eat it. The catch? There are only nine licensed growers in the world. Ryan and Anjali are joined by three experts to talk about the science behind this amazing plant, the benefits we’re already seeing from the animals who eat it, and the next steps for scaling up its use by farmers around the world. Learn more about our flagship conference happening this April at attend.ted.com/podcast Hosted on Acast. See acast.com/privacy for more information.

Happy Sunday, TED Talks Daily listeners. It's Elise Hugh. As we often do on Sundays, today we're sharing a recent episode of another podcast from the TED Audio Collective, handpicked by us for you. This time from our podcast, Speed and Scale. Did you know that cows emit methane even when they burp? Livestock account for more than 12% of the world's greenhouse gas emissions, but farmers and scientists have discovered a superfood that might be the key to lowering emissions and raising healthier cows. In this episode, hosts Ryan Panchatsaram and Anjali Grover investigate the mystery of asparagus, a seaweed variety that removes methane from the guts of the animals who eat it. The catch? There are only nine licensed growers in the world. Ryan and Anjali are joined by three experts to talk about the science behind this amazing plant the benefits we're already seeing from animals who eat it, and the next steps for scaling up its use around the world.

To hear more inspiring stories about the people accelerating solutions to the world's greatest climate challenges, listen to speed and scale wherever you get your podcasts. Learn more about TED's podcasts at audiocollective.ted.com. Now on to the episode right after a quick break. Okay, Ange, our story starts with a dairy farmer. His name is Joe Dorgan. His farm is a mix of green pastures and rocky red coasts. About two decades ago, Joe noticed.

something strange going on with his cows. The ones who were eating seaweed by the beach were doing better than the ones who weren't, the ones farther away. Interesting. How so? They were making more milk. They were better behaved. And in Joe's words, they had rip-roaring heats, which means it's easy for them to get pregnant. And in the dairy business, that's important because to keep making milk, they have to have babies. So there's something in the seaweed that's special, like a superfood for cows. Exactly. That's how Joe saw it too. The seaweed could be interest to other dairy farmers, and he decided to capitalize on it. But Joe couldn't sell it by himself. Canada has this little thing called the Canadian Food Inspection Agency, and they regulate

whether or not you can sell things into the livestock feed market. So in order for him to satisfy them, he needed someone like myself. This is Rob Kinley. He's the agricultural research scientist that Joe reached out to. He agreed to test the seaweed and its effects on cow's stomachs, but also for people drinking the cow's milk. So he started testing, but he also took it one step further to investigate if there were any changes with methane. Oh, how did you think to test for the methane? Well, in his past work life, he studied methane. He was concerned about how methane was a super greenhouse gas, way worse than CO2, and he knew cows produced a ton of it by burping it up. So he decided to see how much Joe's cows, the ones on the seaweed diet, were emitting.

We were in a laboratory and I was fermenting grass using microbiology from cattle, and that was creating that gas. And I couldn't let it go just into the room. It had to be exhausted. So instead of letting it go into the exhaust system, I could capture the gas into the balloon, which is like one of those birthday balloons you would buy. Crazy, that's how you measure methane with a balloon.

Yeah, so Rob measured the methane gas and the results took them by. surprise. Lo and behold, I saw almost 20% reduction in methane emissions. Now, back in 2005, 2006, 20%'s a big deal. Back then, it was the starting point. So my light bulb moment, somewhere in the world, there's going to be a seaweed that can do better than 20%. Rob started looking for that special seaweed.

And in just a few short years, he ended up working with experts in Australia who knew lot about seaweed chemistry. Turns out, Australia was also funding ways to reduce methane from cows and sheep. We all came together to be able to start to screen tropical seaweeds off, you know, the same coast with the Great Barrier Reefies. In just six months, he found his golden seaweed. It was called asperagopsis. It's actually quite beautiful in the water. It can be pink or light brown, and it looks like a fluffy fern. When Rob Tessesson, tested it in the lab, he couldn't believe his results. I couldn't find any methane.

Wait, no methane at all? Yeah, and Rob didn't believe it either. I was like, my God, this can't be true. The instrumentation's broken. It's just not working. Our measurements aren't right. Our feeding values are wrong, where somebody's messing up the mixing of the feed. I was looking, turning over every stone. He conducted the experiment three more times before his skepticism started to be

placed with belief. And then even after that, when I was convinced I could do it in the laboratory, I still didn't think I'd be able to pull that off in animals. Rob and his colleagues started with the sheep. They gave them a very small amount of seaweed, like 3% of their diet and mixed it in with their regular food. The sheep didn't eat the seaweed, and we were still seeing 80% reduction in methane. That was our first indication. That was when I knew we had something remarkable going on here. The fact that those sheep only had a little bit of seaweed in their diet told Rob that you didn't need to feed them that much of it. So he reduced the amount.

And he found out that he only needed less than 1% of seaweed to reduce methane emissions. Only 1%? Yeah, I know. Rob's sheep trial led to another trial, this time in cows, which led to even more trials. All of them confirmed that seaweed was reducing methane emissions from cows and that you didn't need much of it. So should we feed seaweed to all the cows on the planet? Can we create methane-free beef? That's what we're going to find out.

Hi, everyone. I'm Ryan Pinchotseram. And I'm Anjali Grover. Welcome to Speed and Scale, a podcast from TED. This is the show where we focus on the best strategies to tackle climate change. Today, we're digging into a solution to stop an underappreciated villain in the climate crisis, methane. So eating beef and drinking milk, that's a big culprit of methane emissions. which is why we have to replace a lot of beef and dairy with lower emissions alternatives. There's no question we've got to do that, but I think we all know it's hard to give up something you love.

In this case, burgers or steaks, or cheese. Or pizza. So it's also useful to have something that'll make it possible for us to keep eating what we want to eat. And that's where seaweed comes in. Okay, is a plan to feed seaweed to every cow on the planet? Is that actually doable? Yeah, it's a lot of seaweed, and there are a lot of cows. One and a half billion of them, in fact. And there's some caveats, like the seaweed doesn't grow in abundance all over the world.

It needs to be farmed. We need about 100 million tons of it. But as of 2024, just 35 million tons of seaweed was farmed globally. And only a tiny fraction of that is asparagus. I needed to figure out how fast we can actually scale up this solution. And I also had so many questions. I probably stayed up for a few days reading through all of the studies and said, no way, this can't be happening.

And then I'd read the next study, and they'd saw the same sort of reductions with this red seaweed. That's Brianna Roke. She's an animal scientist. And at the time that I spoke to her, she was working with Rob at Future Feed. She's obsessed with the seaweed and knows everything about it. Brianna, how effective is the seaweed in reducing methane in cows? So beef and dairy are, you know, they're both cattle, but they're very different. What we've seen so far is we can get a.

as high as 80% reductions in dairy and over 98, 99% reductions in beef feedlot animals. So dairy cattle eat probably twice as much as a normal beef animal would. So naturally, they're going to produce about double the methane content of a beef animal. And does this change during the lifespan of a cow? Like, does this intervention, does it only work at one part of their life or throughout their lifespan? It should work throughout their lifespan. We've seen studies well over 200 days and there's no loss of the effectiveness of asparagopsis

to reduce methane emissions. But different life periods of animals pose different complications, if you will, to actually apply the asparagus. So young beef animals aren't in a feedlot. They're grazing. And grazing animals is really hard to get them an additional feed additive or ingredient because they're just out grazing. So it's still an infant in terms of feed additive progression.

And we're working through these complications to provide a better asparagus's product as time goes on. And so that's a perfect segue to scale. And let's talk about scale. How scaled up is this idea at this point? Like how much seaweed is growing right now and maybe how many cows are eating it? There are nine licensed growers so far. all over the world that are scaling up asparagus's production to be able to fit into livestock systems. And those licensed growers, they've made significant progress on scaling

up their systems over the past four or five years to where they're ready. And some of them, particularly in Australia, are in the market already. And when you mean ready, does it mean it's being actively used in feed lots. In Australia, asparagus is approved to be fed in production systems. That is different globally, right? There's different regulatory bodies that all want to check to make sure that it's safe and effective, of course, within their own systems. But in Australia, the licensed growers are able to sell into the production systems of

their choosing. So some have specifically targeted beef feedlot systems. And so there's even a burger chain in Australia that sells what they call a game changer burger. That's awesome. Yeah, it's really exciting. And the meat they're selling for this game changer burger is coming from animals that were fed asparagus. Oh, that's incredible. Okay.

So there are growers that are growing it well. There are feedlots that are adopting the practice. And then there are burger chains that are using it. Can you tell me more about this burger chain? Have you had one yet, Brianna? I have, yes. Of course. It's only in certain areas, but one of the restaurants was in Brisbane, which is where the Future Feed headquarters are. So I go there often, and I definitely made sure to stop by and get my game changer burger. How did that feel? How did it taste? It was wonderful. Actually, so I had my mom and my best friend visiting me from California,

and so we all went and we all had a game changer burger, and it felt really nice. you know, like a lot of the science gets stuck in the lab. And then here we are sitting, eating game changer burgers contributing to environmental sustainability for livestock systems. Oh, that's incredible. I mean, so you're seeing it in your neighborhood. And I mean, I want one. I think that your friend coming from California, I'm jealous. And so how fast, how fast is this solution scaling up? And where in the world could it scale up the fastest, be grown the fastest. I see Australia as being the quickest, almost kind of demo area where the asparagus can be grown up to scale pretty quickly here. And I say that because first, asparagus is native.

And so the waters that are used to grow the seaweed are conducive to what it needs. And the second reason I say that is because it's approved to be put into a feedlot system or, any sort of livestock production system here. And that's not the same case for all around the world, right? So I think the biggest limitation that we have currently is the regulatory system globally. So as soon as we can get through all of the regulatory hurdles that are regionally specific, then scaling up is actually going to be quite easy. Well, that's fantastic. You know, today, Australia seems to be the home kind of base for this. all the innovation. I'm kind of curious how you see the solution scaling up across the world in the

near future. And I just want to get that approval. What do you have to do? It depends on the area. And so for the United States, for instance, it's considered a drug. And so that approval is lengthy. And so we're working with the FDA to see what we need to do in order to satisfy their conditions. looks like we need to do quite a few studies in the United States working with animals that are there. But other areas such as the EU have classified as baragopsis as a feed material, which means that producers within the EU can feed it on farm today. But they can't make methane claims.

If they want to submit into the carbon crediting system, they need to be able to make those claims. And so we're also working with the food safety authority within the EU to show that it is effective, how effective it is within the different production systems they have, and that it's safe. And who's pursuing these regulatory hurdles in the biggest, you know, beef consuming, dairy consuming countries? It's really kind of an all hands-on deck type of thing. Where can we do these studies? How can we get the funding to do these studies? and how do we work with regulatory bodies to show them that this is a safe and effective product? We do a lot of collaboration. I think that's really the only way forward.

And so we work a lot with the licensed growers to look at what products that they're actually making and what is the quality of those products and how they fit into a production system. And then also we collaborate with research centers within the area that we're seeking approval. Got it. So you not only have to prove and show that it's safe, but you also have to go through the measurement and reporting and verification piece too. When you think about companies that sell beef at scale, of course, burgers come to mind, the McDonald's of the world. And, you know, what collaboration are you seeing from these companies? Are they investing in these technologies to help meet their sustainability goals? What are the big, call it the big giants doing?

You'll notice that some industries such as Chipotle, even Mitsubishi, has invested in some of these licensed growers to kind of help scale up and get this to market. You know, we need these industries in order for this to be successful. Do you know why they're getting involved? Like, what's in it for them? A lot of companies have sustainability goals, particularly for companies that let's use McDonald's for an example. they do a lot of animal products. And for a feed additive that's relatively easy to add into a production system, that's probably the easiest and also the fastest way to reduce emissions within their system.

Got it. Can you maybe talk more about the safety of seaweed? Because I know so far studies have shown that it's safe for feeding it to cows and for humans to eat the meat. But, you know, we've read a bit about some of the concerns about the ozone and research on needing to make sure the dairy's safe. But are there any limitations of these safety studies that we've got to be on the lookout for? Seaweeds are very high in minerals, which is great, but you don't want to over-consume minerals, right? So there's a limit on how much you should be consuming. And so we do track and measure particularly iodine and bromine within the asparagus, fed to the animal,

and what do the products look like on the back end. So this is why the licensing of asparagus, growing is so important is because it creates a global standard for what the quality of asparagus should be. And I do think it's important to note, particularly within the beef systems, that these bioactives are never found in the meat, fat, any of the organs. So it's really contributing to the overall safety piece of the asparagus's story. This is great. What about the cost of the seaweed? Can the farmers, the cattle farmers, can they afford it? I'm very aware that livestock farmers spend between 60 and 80% of their total costs on feed.

And so what they don't need is an additional cost of feed to put into their system. That's where large industry can come into play. With that said, the other thing that we see that's really promising with the spericopsis is not only is it reducing methane emissions, is also increasing productivity within the animal. When you say increasing productivity, what does that mean? When we look at productivity, it's usually on a basis of how much weight gain can we achieve with one unit of feed. And so what we see with asparagus is actually that we can put on more weight with the animal with less feed.

Oh, wow. We just published a study in 2024 that showed up to a specific. 7.4% improvement in productivity, which was associated with reduced feed costs. Oh, that's so cool. And do we know why, or why that works, Priyana, from the science side? We have some theories. So our hypothesis is that we do know that there is energy within the animal being lost to methane production. When you reduce methane emissions so much, So over 80%. That energy can be redirected into the animal for things such as weight gain.

Wow. How much money will this save farmers? So in a study that we had published within the United States, we had estimated that for a farmer that's got a thousand head of cattle, whether that's beef cattle, potential savings for them could be between $47,000 and $87,000 for that thousand head of cattle, depending on what their asparagus inclusion levels look like. Well, that's incredible.

I mean, I really do hope that this not only saves farmers' money, but then there's a reason to pay more as well, too, for cattle raised this way. In speed and scale, we believe that there's so many ways to accelerate things. And, of course, businesses buying and consuming and using as one. But what about policy, the politics and policy side? Are there policy incentives that could speed this up? Yeah, policy. is tricky. So in Australia, what I've seen the government do is they've invested a significant

amount of money and resources into products that could be viable for the market. And so they have this program. It's called methane emission reduction in livestock or maryl. And if you have a product, such as as asparagus, or, you know, there's quite a few different products, you can apply for these grants and show on farm that it's safe and effective in a commercial setting. And so then the government takes all of those studies and they look at it in terms of how do we analyze this data, how do we estimate methane reduction for the rest of the farmers? And then how do we put together a policy that says, okay, if you're using asparagus, you can claim 65 or 70% reductions or whatever you have based on your inclusion level so that you're not actually measuring those emissions on

farm. In other areas, let's pick on California, for instance, they have a Senate bill that mandates every industry in California to reduce their emissions by 40%. And so it's almost a scramble for farmers to figure out how to do that in a cost-effective way or, you know, a way that doesn't require a lot of investment. And so one way that would be really great is if they had a feed additive that they can apply to the system that reduces methane emissions by, let's say, 80%. Then they're doubling what the policy is requiring them to do. So governments can either use a carrot or stick, right? Incentivize companies to make products reduce methane or require farmers to reduce their emissions.

Any big takeaways I'm working on this solution? Seeing this all take shape? Oh, look, it's really exciting to see asparagus go from this little tiny vial in the lab to being fed on farm to thousands of animals. That feels really good. Oh, I can't wait to try that burger. I feel like it's the holy grail, Brianna. It's the holy grail. Come to Australia and we'll get you a game changer burger.

Okay. So what did Brianna tell you? Brianna was great. She helped me check off all the boxes to figure out if this seaweed solution is scalable. Does it reduce methane from cows? Yes. Is it safe for them to eat? Yes.

Can the solution scale? Can you actually get the seaweed? Yes and yes. Wow. Where can you get it now? Are cows eating it? Yes. It's available in Australia.

Brianna has actually eaten a burger called the Game Changer from a place called Grilled. I actually found the guy who grew the seaweed for that burger. His name is Sam Elsem. The founder of Grilled was really interested in understanding what is the consumer sentiment around this. And so they offered the burger at a dollar premium, and they wanted to understand what was the uptake. What they found, which was fantastic, is that one in three customers were willing to pay that extra dollar. And so that gave them strong enough confidence to drop the dollar and make a part of business as usual. Sam told me he's working with the restaurant chain that serves these burgers to bring more of them to their restaurants.

Wow, that's awesome that there's already a market for this and that people are actually spending more on a climate burger. It's really cool to see these solutions happening in real life. How is Sam getting farmers to buy his seaweed, though? Farmers are notoriously sensitive to new practices and higher costs. You know, I asked Sam about that, and he said that's his biggest challenge. But he said recent studies show the seaweed can help farmers save money. And that's going to tip the scales and get farmers to adopt this. He's not just relying on the cost savings, though.

We know that farmers can't afford additional costs. We know that there's value to the farmer and to the supply chain. So we've been contracting a number of farmers in Australia. We've had most of Australia's major producers come and visit us down in Tasmania, learn about our product and the work that we do. We've been working with a number of chefs who have restaurants around the place, so they're starting to tell that story through their menus. I think that through enough consumers making those choices,

it also shows that there is demand. And demand is also what's going to change behavior at a farmer level as well. So basically, Sam is educating farmers and chefs. And he also highlighted the importance of support from companies at the end of the supply chain. For example, in February, the global food giant, Mars, announced that it would give $27 million over a five-year period to help dairy farmers reduce their emissions. Okay, so adoption is a major hurdle on the demand side. But let's talk about supply. Where are we at now?

How much seaweed has been grown today and how much does it need to scale? So in Sam's case, when he started growing seaweed back in 2018, there was no industry. But now fast forward six years and his business is on the cusp of taking off. He told me that his seaweed production is going to triple this coming year. We have aggressive scale up plants. We have operations now in the UK. We're working towards Brazil as well. We have an effort going in North America as well and have partners like supply chain partners that

we're working with over there. To put his efforts into perspective for you, he grew 1,500 tons of asperagopsis last year, and that feeds 82,000 cows for a year. You've got nine other growers around the world growing the same seaweed. I don't have their numbers, Ange, but if they were growing the same amount of asperagopsis, that's about 15,000 tons, or enough for about a million cows. Wow, okay, so we're still a very, very long way from the 100 million tons of seaweed you said we'd need. Yes, we are. But keep in mind that these key findings for the solution have just come out. And you've got trials still happening around the world.

They've been cleared to sell in Australia and Europe, but they're still working with the FDA and the U.S. Once those hurdles are cleared, things will accelerate. This is awesome. Here's my question. If we get to a world, Ryan, where we can feed every cow this seaweed, can we have our steak and eat it too? Not quite, because raising cows is one of the main causes of deforestation. So we're going to have to consume less. But this does take us one exciting step closer to lower emissions dairy and lower emissions beef.

For those times, we just can't do without that cheeseburger. Speed and Scale is a podcast from TED. It's hosted by me, Ryan Pinchotsdam and Anjali Grover. This episode is produced by Sarah Craig from Pushkin Industries. Production support from Pali Emlin. The show is edited by Ban Ban Cheng, and her fact checkers are Julia Dickerson, Kate Williams, and Jen Nam. The show was sound designed and mixed by Hans Del Shee,

our executive producers are Daniela Balereseo and Constanza Gallardo. Special thanks to Jonathan Mallow and Roxanne Highlash.