Best of: How the humble refrigerator changed the world
31:23 Share

When you're with Amex Business Platinum, you have the card that works just as hard as you do. You give 150% to your business and so does your card. With 1.5 times membership rewards points on select purchases, you earn rewards that can take your business further. And with complimentary access to more than 1,400 lounges globally, including the Centurion Lounge, you can stay up to speed no matter where your business takes you. That's the powerful backing of American Express.

Terms and points cap apply. Learn more at americanexpress.com slash amxbusiness. Hi, it's Akshat. While some of us enjoy downtime this week, we're bringing you a cool wintry episode that should pair well with any leftovers from your holiday cooking. It's about refrigeration and the nearly invisible cold chain that makes it possible for us to eat the 21st century diets we enjoy.

And it's something that Nicola Twilley, who I spoke with earlier this year, thinks we don't pay enough attention to. So take a listen and enjoy. We'll be back in the new year with a fresh episode with the writer Kim Stanley Robinson about his climate visions for 2025. Welcome to Xero. I am Akshat Rati. This week, the cold rush. There's plenty of mistakes that happen in all that. Produce is...

full of little small decisions. If you bat like 90%, you're doing great. So I'd say 90% of what comes over here is perfectly good and then there's always the second wave of our inspections. That's a guy inside a fridge. A really big fridge. His name is Matthew Dorigo and he's giving a tour of a cold storage facility in the Bronx. Matthew's family has been in this business for generations. We're dealing with a perishable product.

It's grown under interesting conditions that are all different. A century ago, they were responsible for the first transcontinental shipment of broccoli from California to New York on a refrigerated train. Those were the earliest days of the cold chain. Now, those of us in developed countries take it for granted. Today, three quarters of everything on the average American plate is processed, packaged, shipped, stored or sold cold.

You know cold storage facilities exist, but I bet you don't know just how big these spaces have become. The US alone boasts around 5.5 billion cubic feet of refrigerated space. That's like 150 Empire State Buildings worth of freezers. And developing countries are starting to catch up. Between 2018 and 2022, the whole world's chilled and frozen warehouse space increased by 20%.

At a time when ice caps are melting faster than ever, the number of walk-in refrigerators is also expanding. This cold rush has huge implications for the planet. It's something journalist Nicola Twilley has thought a lot about.

She's explored quite a few giant freezers like the one Matthew works in. That's because she's the author of a new book about how refrigeration has shaped our food, ourselves and our planet. It's called Frostbite and it's a really fun read full of crazy trivia like the fact that the Irish independence movement might have refrigerated beef from the US to thank for its success.

Now, refrigeration is considered a climate solution. More than 30% of all food produced on farms in poor nations never makes it to a store. And a cold chain can help reduce that food waste. But on the flip side, it turns out that having access to refrigeration can also lead to food waste. Americans waste more than 30% of their food in their homes because they hoard so much in the fridge. That's why I was excited to talk to Nicola.

Because the humble fridge is going to play a big part in our planet's future. Nicola, welcome to the show. Thank you for having me. Now, let's start at the beginning with the invention of refrigeration. It's one of those modern miracles that few people think about and most people take for granted. But the road to inventing the fridge was quite long. Can you take us back in time and talk us through how it happened?

Yeah, if you think about it, humans have had control of fire since before we were modern humans. And yet we haven't been able to produce cold at will until...

maybe 150 years ago, max. So it's sort of an incredibly recent invention. And it's not that early humans had no idea that cold would preserve food because they noticed that right away. It's just that there wasn't a sense of how to control it or even what cold was. It was actually...

All of the great minds of scientific history, Galileo, you know, Francis Bacon, Robert Boyle, Leonardo da Vinci, they all kind of wrestled with what is cold? And there was theories that, oh, it's maybe, you know, these frigorific atoms, or maybe it's sort of a force that gets distributed from the North Pole, or rises up from the ground, down from the air. No one had any idea.

It was actually immensely frustrating for people. Francis Bacon died while he was trying to figure it out from a chill caused by trying to stuff a chicken with ice. So it really took a long time to work it out. And actually, even when the first person to sort of create Cold Artificially was

a Scottish doctor named William Cullen, he sort of did it as a party trick because it wasn't something you could do at scale. It wasn't seen as something that would work to refrigerate our whole food system, let alone, you know, the way we use air conditioning now, you know, our factories, houses, data centers.

He just managed to evaporate some ether under pressure and freeze a flask of water. And no one looked at that and saw the potential for another 75 years.

And the first refrigerating machines were just enormous and blew up all the time and were incredibly dangerous. All of the early pioneers just constantly losing eyebrows and, you know, fingers and all the rest of it. So it took it took a very long time. You know, the first commercial machine was the 1850s. It doesn't become domesticated, something that we can actually have in our homes until the 1920s.

So that's 100 years ago. It's really recent. And it was shocking to know that you just went and built a refrigerator for yourself for this book. Is it really that simple? Well, so I have an embarrassingly long way through the writing of this book when I realized I too really didn't understand how to make cold. Yeah.

I was like Galileo. I had no idea. You know, I was looking at how cold had reshaped what we eat and where it's grown and how it tastes and how good it is for us and the planet. But I didn't understand how we made it. So a friend of a friend runs an HVAC startup and he said, well, come to my garage. We can build a fridge here.

And I was like, you can't just build a fridge, but it turns out you can. Now, to be fair, this was a bit more like when you make dinner from, you know, jarred pasta sauce and a rotisserie chicken and some pre-washed, you know, spinach leaves or something. I wasn't actually building all the elements from scratch. So we had purchased a compressor. We had purchased an evaporator. We had purchased this.

the various, there are sort of four main components. And what we did was join them up in such a way and then charge it with refrigerant, which is the chemical that evaporates under pressure to create the cooling effect. Because if any of your listeners are like me and have no idea what cold is still, it's just the absence of heat. And so cooling is that sense of loss as you remove heat

And so what you want to do, if you remember from high school physics, which I completely did not, is when a liquid evaporates into a gas that takes energy and you suck that energy in from the atmosphere around you as heat energy, thus creating the sort of sense of loss as all that heat energy is pulled away, the cooling.

And so it's a really simple system. The trick is, of course, to create, you know, you do that once. That's what William Cullen did in 1755. The trick is to keep doing it and create a circuit where it just goes round and round and round and keeps evaporating. But even that is surprisingly simple once you've built it. It's just something that I think is so invisible to the majority of us that we never think about it. Yeah, and a major turning point came recently

when this invention was put to work at scale. And you write, before that, most meat eaten in cities walked itself to market, often over enormous distances. And of course, when cattle is marching miles to an urban slaughterhouse, it's getting skinnier along the way. But once the problem of moving large quantities of frozen meat was solved, all that changed.

And soon beef was being shipped across oceans from America to England. How did this transform the way we eat?

It's an astonishing transformation on so many levels. As you say, I mean, the problem of getting meat and also dairy into cities was really a huge one. Not least of which was that you then had to slaughter them in the city. And so the area around Smithfield Market in London or the slaughterhouses in New York was just...

I mean, can you imagine slaughtering enough beef for a city in the middle of that city in summer, say? I mean, it was nauseating. There was blood, guts, foam, froth. It was absolutely...

horrific. And bringing meat from places like Argentina, New Zealand, Australia, where there was vast amount of land, not a lot of people, it lowered the price of meat immediately. I mean, by a quarter at least. And so suddenly poor people who had not been able to have meat except on very special occasions could dine on meat frequently. You know, red meat consumption went through the roof.

And today we think of one of the climate solutions is to try and eat less red meat because it produces so much greenhouse gases, mostly from cows belching methane. However, this increase in meat consumption happened partly because of the ability to move cheap meat around, but also because science at the time, for some reason, at least in the West, was telling people that

The only way to survive is to have more protein and the protein comes from meat.

Right. This is sort of a sad mistake in the history of science. Chemistry was a relatively recent field of research in the 1800s. You know, previously there had been alchemists and they were trying to turn things into gold and find elixirs of eternal life. So it was a relatively new field. And one of the things that chemists were doing were trying to sort out what it is in food that we need. And

And in the early 1800s, some mistaken experiments led them to the conclusion that actually it was only protein. Carbohydrate and fat were just sort of nice to have, not necessary. And no one knew about vitamins. Vitamins didn't come along until the 1930s. So, yeah.

So protein was the be all and end all. And that discovery coincided with the expansion of cities to the first time that London was sort of going from a million people to 2 million people to 3 million people, the largest cities the world had ever seen. And as we talked about, getting meat into cities is really hard. So you have this

sudden sort of scientific realization that if we are to have, you know, strong men to work in factories and make the nation great, they must be fed with protein. And the fact that we can't get protein to them. So it was an utter panic. Of course, you know, they could have had lentils. But the scientists at the time weren't looking at lentils for their protein content, they were looking at beef. So

So, I mean, we could have had a very different world if those scientists had been like, we all need to eat lentils. It's all a sort of misunderstanding, but it shaped our modern food system. We recently did a whole series on the show about the power grid. And in a way, you can call it the world's biggest machine because everything works in sync.

And when I was reading the book, it made me think that the cold chain is kind of similar. It's a giant system. Yes, it's not in one place and it's not connected all the time, but it is connected. So was it one of your hopes that when people read the book, they realize this standalone home appliance that you have is actually part of a huge system?

Exactly. Yes. And that's why in the chapter where I look at the domestic refrigerator, I call it the tip of the iceberg. I mean, within the industry, our food, our perishable food supply system is called a cold chain with the idea chain that it is connected from your farm to your fridge.

The domestic fridge is really the weak link because once you pick it up at the supermarket, then it sits in your car or in your bike rack or, you know, shopping bag and isn't refrigerated on its way home. But up until that point...

say a green bean, within an hour or two of harvest can have been brought down to a certain temperature and kept there all the way to supermarket shelves. So I ended up seeing it as a sort of distributed winter and it's entirely connected by this network of refrigerated shipping containers and ships and trucks and trains.

But it isn't visible as one gigantic winter. It's a series of sort of pockets of cold. And this artificial winter that our food spends time in, moves around in, it's actually enormous. But because you never see it as a connected whole, you don't realize. Now, this artificial winter does sound very energy intensive, right?

Were you able to put a number on the amount of emissions that are attached to refrigeration? Yes, it's a difficult one to get an exact number on. And of course...

you're not taking into account sort of the expanded emissions that come from, say, being able to eat more red meat because you can cool it. So leaving aside those sort of knock-on effects, cold storage companies are currently the third highest industrial consumers of energy. So the power to run cooling equipment is more than 8% of global electricity usage right now. There's energy use, but of course there's another warming impact too.

to consider in refrigeration. And that's to do with the refrigerant, the gas that moves around, is compressed, is evaporated. In the early days, that gas was a poisonous gas, typically ammonia or sulfur dioxide, and it caused a bunch of accidents and the industry was forced to find an alternative, which it did, and was pretty effective, except it was

chlorofluorocarbons, which turned out to not be poisonous but created a hole in the ozone layer. So one of the most successful environmental treaty comes out of that desire to change the refrigerant one more time from CFCs to what became HFCs, which did not create a hole in the ozone layer but are super warming gases. They're thousands of times more warming ton for ton for CO2.

Now we are at that point where we need to eliminate HFCs as well. So what are the choice of refrigerants that we have today and what does innovation look like?

So, yeah, that's a great question. There are lower global warming potential, as they call it, GWP refrigerants coming on the market. Many refrigerated warehouses and such like are moving to ammonia systems, for example. We're going back to the poisonous gas. It's very dangerous. Except we can handle it better this time, I'm assuming.

Well, I mean, if it leaks, I had a graphic description from a guy who runs a refrigerated warehouse who said, you know, when you see that white cloud, you're seeing death. It wants your crevices. Apparently it goes for your eyeballs. It's just really scary.

a nasty chemical. And so one of the problems actually is that the cold chain is expanding everywhere. It's expanding even in countries that seem as though they already have plenty of refrigerated space, such as the United States, but it is expanding fastest in parts of the world that don't have a cold chain currently. So sub-Saharan Africa, large parts of Southeast Asia, and

Those places are building a cold chain from scratch right now. And they are also not typically equipped with a lot of trained engineers who can work with these dangerous gases. And a lot of the replacement refrigerants are much harder to use, flammable, toxic, just inorganic.

difficult and require more sophisticated machinery. So it's really a hard thing to replace these HCFCs and HFCs with these new refrigerants in places that already don't have enough engineers to make the simple non-toxic refrigerants work.

So that's one of the huge issues. And actually now there's a huge black market in HCFCs and HFCs because they're cheaper, easier to use, the old equipment runs on them. And so even though they're being phased out or even in some cases banned, they're still widely traded and widely used because they work and people know how to use them. So that's a huge problem. But to me, I thought the most interesting thing was not...

to think about the future of refrigeration beyond just, okay, how do we make a better refrigerant? But can we make a better way of cooling? And even beyond that, can we make a better way of food preservation? Food preservation is the goal here after all. Cooling is just how we do it. And you also traveled to China as part of your reporting. Yes.

Now, I went to China last in 2018, so it's been a while. But having traveled to the U.S. and the U.K. before I traveled to China, I was kind of shocked by how developed the country was. Infrastructure was fantastic. The fast trades were really fast. The system to pay was easier. You could use apps, etc.,

But you found that the cold chain wasn't developed enough. And that was a little bit surprising to me. Why is that the case?

Well, that's changing really, really fast. So China made building a cold chain, a modern cold chain, part of its 12th five-year plan. And, you know, when China sets out to do something, they really do it. And so it took a while and it was uneven. You know, the major cities had much better refrigerated facilities. The rural areas had nothing.

And there were gaps and, you know, people would say to me, oh, we would import, you know, chicken and it would come in beautiful and at the port it would be kept cold. And then we would find it, you know, five days later in a rural distribution warehouse with just a wet towel over it to keep it quote unquote fresh. So it was a work in progress when I went, but it's accelerating fast. And I would say,

China, it's a huge country. It has a huge food system. Its cold chain is still only one sixth the size of the U.S. one. So there's still, you could argue that the U.S. one is bigger than we need, but there's definitely still room for growth in China. But you can start seeing that it's really getting there. So for example, Washington State cherries used to be air freighted to China because they

They were popular as gifts and you couldn't get decent cherries imported from the countryside in China because the coal chain didn't exist to get them to the cities. So it's easier to import them, air freight them from Washington state. Wow.

than bring them in from the countryside in China just because the cold chain wasn't there. That's changing. So now it's making less economic sense to air freight them. And as the cold chain is built up in China, more economic sense to bring them in from the countryside. And you can see that change in sort of real time. Washington state farmers are adjusting to that because the cold chain in China is picking up.

After the break, how refrigeration can reduce food waste. Or, if you're not careful, increase it. If you've been enjoying this episode, please take a moment to rate and review the show on Apple Podcasts and Spotify. It helps other listeners find the show.

When you're with Amex Business Platinum, you have the card that works as hard as you do with a flexible spending limit that adapts with your business. That's the powerful backing of American Express. Not all purchases will be approved. Terms apply. Learn more at americanexpress.com slash Amex Business.

Having seen enough refrigerators in America over the years of traveling to America, oh my god, American fridges are huge and they really don't need to be. But on food waste itself, there are two stories to be told when it comes to refrigeration. On the one hand,

In developing countries, where you still get a lot of agriculture being part of the economy, not having a cold chain can lead to a lot of food waste as the food travels from the farm to the consumer because it rots in the process. On the other hand, having access to refrigeration in developed countries means people just buy a ton of food and think it's going to be all okay in the fridge and

It isn't the case and a lot of food is wasted in refrigerators. So how do we actually try and figure out how to reduce food waste and use refrigeration as a benefit not a loss?

Yeah, it's a really interesting problem. You know, food waste is often touted as the reason to build a cold chain in countries like I visited Rwanda with a with a UN sponsored sort of effort to bring the cold chain. I mean, people are losing 30 to 40 percent of the harvest before it ever gets to market. Now, that's a horrific waste in a country as poor and poor.

you can't afford to be losing that much food. So you can see why there's a desire for a cold chain. The problem, as you say, is that in the developed world, we are throwing away 30 to 40% of our food at the retail and consumer end. The abundance that refrigeration has given us is translated into a sort of lack of care, a willingness to waste. The food is so plentiful and so cheap that people would rather go and buy something else instead.

I mean, honestly, rather than sniff their milk, because obviously sniffing off milk will kill you. Everyone knows that. They would rather pour it out and buy, you know, just trust the sell by label and buy another pint. And that's that is an impact of refrigeration, too. So some of the things I looked at here are, first of all, sell by dates. Ridiculous.

There is no sort of logic to them. I mean, in the U.S., it's a particular mess you have because it can be state by state. So in Montana, milk will expire a week earlier than it will in the rest of the country. There's nothing particularly, you know, poisonous to milk about Montana. It's just the system. So that's ridiculous. You know, people have tried to come up with all kind of smart fridges and technological solutions here. To my mind, the things that work most effectively are

are actually ways to save food from the refrigerator and make it visible. So there's a few different things. I mean, one, there's a quote from an architect I love that says small fridges make good cities, but we know this with motorways. When you build a bigger motorway, you get more traffic is what actually happens. People think it's going to be great and, you know, traffic. No, it's the theory of induced demand. Well, it applies to fridges too. As your fridge expands, you just stock it.

And then more goes to waste. And so small fridges, shopping on a more frequent basis. So you have to go to the store and you're actually thinking about what you're going to eat for dinner that evening rather than shopping for some distant sort of two week horizon. When obviously things are going to change and you're not going to feel like, I don't know, spaghetti bolognese when it turns out to be a sunny weekend, you know, and so...

So a lot of those sorts of things are important.

In people's minds, a fridge nowadays is actually like a bank vault. Like you put things in it and they stay safe. That's not actually the case. The, you know, the produce is still dying. The meat, the bacteria on the meat are still reproducing. It's just happening more slowly. But it is not a safety vault that will keep your food good forever. And so I think I find keeping food out of the fridge, not milk and meat, obviously, but fruit and vegetables, absolutely.

actually reminds you that it's there. It tastes better when you eat it. Tomatoes, peaches, things like that should never be in the fridge anyway. That knocks out their flavor-producing mechanisms. They will taste worse. Bread should never be in the fridge. Potatoes, onions, these things should never be in the fridge. So yes, saving food from the fridge, shopping, buying less, those kinds of things. One of the refrigeration experts I spoke to

found that she's working on a project that was using urban agriculture not to try and feed the city because you can't do it at that scale but as a way to remind people oh right this this is living produce it is fresh when it is harvested and it isn't fresh a week later and once you are aware of the work that goes in the seasonality things like that people were wasting less food that was what she found so growing food actually had the benefit of people wasting less food

Writing this book, did it change the way you eat? Yeah, it did. I mean, I was already, you know, I make a podcast about food science and history. I write about food. So I was already...

relatively conscious of sort of thinking about where my food came from and things like that. But, and, you know, knowing what's in season when and such like, but absolutely it made me much more aware of the fact that say you buy a bag of spinach, you put it in your fridge, you eat it a week later, you're patting yourself on the back thinking you did yourself, you know, a favor there. You had a healthy bag of spinach, but you didn't waste it. You got all those vitamins and,

No, after a week in your fridge, that spinach has half the vitamins and minerals it did when you first bought it. So having that realization, I think seeing those statistics, it reinforced the fact that it's not getting any better in the fridge. Now, some things get better in the fridge, a curry left overnight, that gets better. But

You know, as bolognese sauce, yes, because, you know, the fat and the collagen has time to sort of solidify and then redisperse and it becomes silkier. But fruit and vegetables, no, don't stockpile them. You know, buy it and eat it. So it really has changed everything.

sort of how I shop and eat. And it has definitely made me focus on seasonality too. Like I just don't eat apples outside of the autumn. And you know what, that's great because there's other fruits you can have in the summer and other fruits. I have citrus in the spring and I have berries in the summer. And it's annoying and obnoxious and I try not to be preachy about it.

but also it all tastes better. Like you really don't need to have a tomato in December. It's going to taste like nothing anyway. Just don't do it. I learned a lot from the book. Thank you, Nicola. Thank you so much. This was fun. Thank you for listening to Zero. And now for the sound of the week. That's the hum of a refrigerator. John Cale of the band Velvet Underground calls it the drone of Western civilization.

It's so constant, he says, that the band would use its steady 60-cycle hum to tune their instruments. That's another great piece of trivia from Nicola's book. And also, check out Gastropod, her podcast about how we eat. If you liked this episode, please take a moment to rate and review the show on Apple Podcasts and Spotify. Share this episode with a friend or with Joe Biden and other lovers of ice cream. You can get in touch at zeropod at bloomberg.net. Zero's producer is Maithili Rao.

Bloomberg's head of podcasts is Sage Bowman and head of talk is Brendan Newnham. Our theme music is composed by Wonderly. Special thanks to Kira Bindram, Aaron Rutkoff and Matthew Griffin. I am Akshat Rati, back soon.