Tristram Stuart: Can Feeding Scraps To Livestock Help Tackle The Food Waste Crisis?

Dec 7, 2018
Originally published on December 7, 2018 10:49 am

Part 2 of the TED Radio Hour episode Circular.

About Tristram Stuart's TED Talk

Our industrial food system is doing serious damage to our planet and food waste is a rampant problem. Tristram Stuart offers one strategy to combat food waste: cook scraps and feed them to livestock.

About Tristram Stuart

Tristram Stuart is an environmental activist working to combat food waste. He is the founder of Feedback, a charity that works to improve the environmental impact of food around the world. Also, in 2016, he founded Toast Ale, a company that brews beer from leftover bread.

Stuart is the author of The Bloodless Revolution, and Waste: Uncovering The Global Food Scandal. He is an Ashoka Fellow, a WEF Young Global Leader, and the recipient of the international environmental award, the Sophie Prize.

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It's the TED Radio Hour from NPR. I'm Guy Raz. And on the show today, ideas about living in a circular world.

TRISTRAM STUART: Food, at the moment, is the single biggest damage that humans do to nature.

RAZ: This is Tristram Stuart. He's an environmental activist. And Tristram, he wants us to rethink our entire approach to food.

STUART: It is the single biggest source of carbon dioxide emissions. It is, by far, the biggest user of freshwater. It is, by far, the biggest cause of species extinction and habitat loss. The soy and the maize that is being grown has, firstly, a huge, negative environmental impact. We are chopping down the Amazon rainforest right now to grow soy to feed to our livestock. That is a monumental and irrevocable disaster for planet Earth.

RAZ: Every year, we throw out roughly 1.3 billion tons of food around the world. That's about a third of what we grow. And Tristram, he wants to change that. Here's more from Tristram on the TED stage.


STUART: Yesterday, I went to one of the local supermarkets that I often visit to inspect, if you like, what they're throwing away. I found quite a few packets of biscuits amongst all the fruit and vegetables and everything else that was in there. And I thought, well, this could serve as a symbol for today.

So I want you to imagine that these nine biscuits that I found in the bin represent the global food supply. OK, we start out with nine. That's what's in fields around the world every single year. The first biscuit we're going to lose before we even leave the farm. That's a problem primarily associated with developing world agriculture, whether it's a lack of infrastructure - refrigeration, pasteurization, grain stores, even basic fruit crates, which means that food goes to waste before it even leaves the fields.

The next three biscuits are the foods that we decide to feed to livestock - the maize, the wheat and the soy. Unfortunately, our beasts are inefficient animals. And they turn two-thirds of that into feces and heat. So we've lost those two, and we've only kept this one in meat and dairy products. Two more we're going to throw away directly into bins.

This is what most of us think of when we think of food waste - what ends up in the garbage, what ends up in supermarket bins, what ends up in restaurant bins. We've lost another two. And we've left ourselves with just four biscuits to feed on. That is not a superlatively efficient use of global resources, especially when you think of the billion hungry people that exist already in the world.


RAZ: I mean, this is - it sounds like there's a - there's several pieces of the puzzle to - that need to be fixed - right? - to resolve this. But it sounds like a big piece of this puzzle is that if we could just use food waste more efficiently, we wouldn't have to grow so much more food.

STUART: That's right. We don't have to grow way more food, particularly not in rich countries. At the moment, we put our food scraps into the garbage.

RAZ: Yeah.

STUART: And a garbage collector comes and takes it, along with all the other trash, and drives it to a landfill site, where it is buried. It decomposes anaerobically - in the absence of oxygen because it's underground - and produces methane, which contributes even more to global warming.

RAZ: Yeah.

STUART: Instead of treating it as a massive economic burden with no value whatsoever - it's just a cost to the economy. That food scraps - just like if you were producing food on a farm or in a restaurant, those food scraps are a resource. They're a valuable resource. And if we collected that food waste, took it to a plant and cooked it and then sent out to farms, that's a business. That is an economically hugely valuable business.

RAZ: So just to clarify, you're talking about recycling our food waste and turning it into animal feed.

STUART: That's absolutely right. The function of pigs and chickens could be to upcycle the byproducts and the waste from the human food supply chain. They're perfectly kind of designed to eat our leftovers and upcycle that waste back into food for us - eggs, meat and also manure, which can go back on the land and feed the crops and the vegetables. And if you think about what happened during the Second World War and, indeed, in the first, where there was a real pinch on food supplies for the Allies, it became illegal to grow crops and feed them to livestock. You could only feed them scraps.

And the systems put in place at that time for collecting every shred of food on every street corner that went to the pigs that then fed the population and fed the armies, now, that was a resource efficiency drive at the time of war. Right? It was an existential threat. Guess what? We have a new existential threat. It is called environmental catastrophe.

RAZ: Yeah. I mean, could it be possible? I mean, could you actually create a system where pigs and chickens are fed food that humans don't eat? I mean, could you do that in an efficient way that wouldn't require, you know, all these soy and corn crops to be grown just to feed these animals?

STUART: The short answer is yes, absolutely. And not only can you, but those systems already exist. If you go to parts of the world like Japan, South Korea, where governments have caught on to the fact that there is a massive resource crisis. And they have their own local issues of having to import, of course, food from other parts of the world.

There are government incentives and government guidelines on maximizing the amount of food scraps from the food system that go into industrial processing plants that cook the food scraps so they're completely safe, totally sterile, and get them out to pig farms and turn back into what is branded as eco pork and ends up on the same shop shelves as the food waste...

RAZ: Wow.

STUART: ...That fed them came from. So those systems exist. They're industrial. They're scaled. They're - you know, that's normal, in fact, historically and geographically. And that is, you know, practiced all over the USA in small bits and bobs. But, you know, there's no reason at all why it shouldn't be centralized.


STUART: Some food waste, as I said at the beginning, will inevitably arise. So the question is, what is the best thing to do with it? In fact, humans answered that question 6,000 years ago. We domesticated pigs to turn food waste back into food. If you cook food for pigs, just as if you cook food for humans, it is rendered safe. If we did that and fed it to pigs, we would save that amount of carbon.

If we feed our food waste, which is the current sort of government favorite way of getting rid of food waste, to anaerobic digestion, which turns food waste into gas to produce electricity, you save a paltry 448 kilograms of carbon dioxide per ton of food waste. It's much better to feed it to pigs.

RAZ: I mean, it sounds like to solve this problem would require an enormous systemic series of policy changes. Like, governments have to harness their power to make this happen. But that also makes me feel helpless, you know, to wait for politicians to solve this problem. And I wonder whether it also requires just behavioral changes among ordinary people to just decide that they are going to try and make a contribution. Is that even possible?

STUART: It's not just possible, we're already doing that. We haven't got anything like as far as we need to. And we need to speed this up way, way, way faster than is currently the case. But if you look at food waste reduction in the U.K., we achieved a 21 percent reduction in food waste in households.

RAZ: Yeah.

STUART: And I believe there is a way of tipping, socially, into a system that completely changes the dominant paradigm in our society and shifts away from pure financial maximization to something much more wholesome. That is not impossible. Financial maximization is a recent construct. It didn't used to be the heart of our society. And it sure as hell can't be in the future.


RAZ: That's Tristram Stuart. He's an environmental activist and founder of the nonprofit craft beer maker Toast Ale. You can see Tristram's full talk at Transcript provided by NPR, Copyright NPR.