This is a transcript of the Gastropod episode Canned Tomatoes and the Myth of the San Marzano, first released on January 13, 2026. It is provided as a courtesy and may contain errors.

JUAN RIOS: We’re going to pull a plant right now, so I can show you guys what we do every day. So if you can see here, you can see some tomatoes on top, right? It looks nice, but… [PLANTS RUSTLING] where the real magic is… under here. That’s where you really see everything.

NICOLA TWILLEY: It’s so nuts how many tomatoes there are.

CYNTHIA GRABER: I’m really shocked.

[RUSTLING]

RIOS: You guys want to hold it?

TWILLEY: Sure! [NICKY LAUGHING]

GRABER: Oh my god! [CYNTHIA LAUGHING]

RIOS: Oh yeah. It’s a good workout for sure.

GRABER: There’s a lot of tomatoes.

TWILLEY: Wow. That weighs a ton.

GRABER: It’s like buried treasure.

GRABER: Nicky and I had each hefted a massive tomato plant into the air and we were loaded up to our elbows in bright red fruit. It was truly amazing.

TWILLEY: And what made it even more amazing was this was just two plants in a field full of them, all covered in perfect red plum-shaped tomatoes. But you could hardly see any of them until you lifted the plants up into the air. From the surface, it was just a carpet of green.

GRABER: We were visiting this tomato field because we promised you a full episode all about canned tomatoes! We of course are Gastropod, the podcast that looks at food through the lens of science and history, I’m Cynthia Graber.

TWILLEY: And I’m Nicola Twilley. And after having so much fun getting into the story of fresh tomatoes and how they lost their flavor last summer, we are back with a winter-themed take on our favorite fruit that is really more of a vegetable.

GRABER: What do the Civil War and Galapagos turtles have to do with the development of this pantry staple? And are San Marzanos all they’re cracked up to be?

TWILLEY: This episode is supported in part by the Alfred P. Sloan Foundation for the Public Understanding of Science, Technology, and Economics. Gastropod is part of the Vox Media Podcast Network, in partnership with Eater.

[MUSIC]

RIOS: We are in Linden, California. At a beautiful tomato field, ready to get picked.

GRABER: Last September, Nicky and I met Juan Rios, he’s the agronomist for Stanislaus Food Products—we joined him in a field near Modesto, in California’s Central Valley.

TWILLEY: And this particular field had a bumper crop. It was, like we keep saying, amazing.

GRABER: It’s an amazing amount of tomatoes buried under all this green. It’s really, really surprising. Like a thick mat of like, a foot of tomatoes. Two feet of tomatoes!

TWILLEY: And when he said carpet, it is. It is exactly. It’s just a lasagna layer of tomatoes, topped with green.

[WALKING FOOTSTEPS]

TWILLEY: I just stood on a tomato and I feel terrible.

GRABER: We both felt a little weird because it was impossible to walk through the field without walking on tomatoes. And why would we want to trample beautiful, perfect-looking tomatoes? But for Juan, that’s a part of the job he kind of enjoys.

RIOS: You want to know, actually, a funny part about standing on the tomatoes? Doing this enough. You have to walk on some of the plants itself when you’re cutting across the field. So I can actually start telling how heavy a crop’s going to be by walking on top of it. ‘Cause you’re not going to feel the ground. You just start floating on tomatoes.

TWILLEY: We really were just floating on gorgeous jewel like tomatoes—I mean truly, this was kind of like tomato heaven. Which, I’d like to point out, is very very different from what you see when you’re looking at a field of eating tomatoes in Florida.

GRABER: As you might remember from our tomato episode last summer, Florida tomatoes, the ones that are destined for the fresh section of supermarket shelves around the country, they are all picked green and hard as a baseball. They are deliberately not ripe. Whereas these canning tomatoes were fully ripe.

TWILLEY: Which is why they were being crushed under our feet, much to our devastation. Fortunately, Juan wasn’t bothered at all. There were just so many tomatoes, all ready at once. That’s kind of what tomatoes do.

BILL ALEXANDER: You know, if you’ve grown tomatoes, you know that their habit is: they come in slowly, and then all of a sudden you get a couple of hot days and they come in like gangbusters.

GRABER: Bill Alexander is the author of Ten Tomatoes that changed the world. And he says this tendency of tomatoes, to gift us this incredible abundance all at once—this was a problem in the mid-1800s, when tomatoes first became super popular in the US.

ALEXANDER: There would be a glut. And the price of tomatoes would drop so much that they would just sometimes plow them into the fields.

TWILLEY: I know, it’s horrifying. But then, and this is a story we’ve told on the show before, in the 1800s, the tin can came along.

ALEXANDER: Now canning started when Napoleon sponsored a a, a contest around 1800 to for someone who could come up with a way for his troops to carry foods into battle that would not spoil.

VOICEOVER: Of course, all growing things are contained within a protective covering, but it occurred to man that if he could provide a permanent protective covering for the bounty of nature, he could then readily extend the harvest season until every day in the year became a day of plenty. A simple idea, but one of great promise. Today, its perfection is a manmade miracle. We refer to it, and rightly so, as the miracle of the can.

GRABER: But It took a while for this miraculous technology to catch on. There were various developments along the way, and a particularly important one was the invention of the can opener in the 1850s. Which was perfect timing.

ALEXANDER: All of this was in place now for just prior to the Civil War, when tomatoes were being grown like crazy. They were already, at this point, the most popular vegetable in the United States.

TWILLEY: The first tomatoes were being put into cans in the US in the 1840s. A gentleman called Harrison Crosby of New Jersey filled metal pails with whole tomatoes, sealed them with a tin disk, and boiled them. He sent samples to Queen Victoria and President James Polk, as well as to hotels and restaurants in New York

GRABER: They caught on. By the 1860s, there were factories in the north—in New Jersey and Pennsylvania—these factories were producing cans, and so Union soldiers could take those cans into battle as part of their rations.

ALEXANDER: Which were always a prize bounty for the Confederate troops who had to rely on raiding the towns and and getting all of their food from the local population. And it was also the first time that many Americans, either in the north or the South, had tasted canned tomatoes. And so when they came out of the war, they actually wanted to keep eating them. And that’s when canning really takes off, after the war.

GRABER: The war ended in 1865, and by 1870, 100 canneries were producing 30 million cans of tomatoes a year. It’s nowhere near what’s produced today, but tomato canning had grown exponentially in just a few years. Soon, there were more tomatoes being canned than any other fruit or vegetable.

TWILLEY: And this is the moment the canned tomato becomes an icon.

ALEXANDER: Shortly after the Civil War, Joseph Campbell joins this canning company in southern Jersey. Buys out his partner after a couple of years. And his conceit was that he wanted to make canned goods that were special, you could buy nowhere else.

TWILLEY: Joseph Campbell is in fact *the* Campbell of, yes, Campbell’s tomato soup. He had been working at a fruit and veg company, and then he joined a canning company as partner.

ALEXANDER: And one of the things that he did was, he had a single beefsteak tomato—a term by the way, that he owned the copyright to. A single, giant beefsteak tomato in a can, which he marketed as Campbell’s celebrated beefsteak tomato. Example, perhaps, of one of the first like real branded foods.

GRABER: You can kind of picture what this canned tomato would have been like. Beefsteak tomatoes are known to be large and round, and the company just skinned and cooked those and stuck each one in its own can. These weren’t their only products, they also had canned vegetables called Strictly Fancy Small Peas, and Fancy Asparagus.

TWILLEY: In the 1890s, Campbell stepped down, a guy called Arthur Dorrance took over as president, and his nephew John who was a chemist with a degree from MIT joined the company.

ALEXANDER: And he comes up to the idea of doing tomato soup. But condensed tomato soup, to which you would add a can of water to, and it would reconstitute back to full soup.

GRABER: And that was it! Canned tomatoes created one of the very first packaged convenience foods.

ALEXANDER: It’s very easy for the housewife. All she has to do is open it. And that same can, fill it with water. And you have a lunch.

SINGER: Campbell’s takes the chill out of children; the way you know a wholesome hot soup should!

VOICEOVER: Hot tomato soup gives them such good nourishment and flavor. They always eat better when you remember the soup! Reach for the Campbell’s, it’s right on your shelf.

ALEXANDER: And many of us are still doing the same thing today.

TWILLEY: The red and white Campbell’s soup can is still an icon, thanks in part to Andy Warhol who famously painted one canvas for every flavor in the 1960s. But the label wasn’t originally red and white. The early Campbell’s soup labels were a quite handsome dark blue and orange.

GRABER: But then in the late 1890s, a guy named Herberton Williams—he was a Campbell’s employee and apparently a football fan—he went to a Penn vs Cornell Thanksgiving Day football game, and he was inspired by the Cornell team’s red and white uniforms. He suggested that for the cans’ new colors, and those labels have remained red and white ever since.

TWILLEY: The late 1890s was a busy time in the life of the canned tomato, because the other thing that was happening was that lots of Italians were leaving Italy and emigrating in search of a better life. Lots of them ended up in the US—millions and millions.

ARTHUR ALLEN: But when all of these immigrants left at the end of the 19th century, early 20th century, they had more money than they had in Italy, which was, you know, very poor. They started like, having this nostalgia for all their products, including canned tomatoes.

GRABER: Arthur Allen is the author of Ripe: The Search for the Perfect Tomato. These Italian immigrants were living all around the world, in the US, in Argentina, in Australia, and they wanted the tomato products they’d eaten back home.

TWILLEY: Last time we talked tomato, we told you the Italians made something called conserva nera with their harvest: this super, super dense thick black solid tomato paste. By the late 1800s, though, they’d switched to bottled, thinner paste, much more like what tomato paste is today.

GRABER: But then they started canning whole tomatoes for the British market. Brits at this point loved tomatoes—they even ate them for breakfast.

TWILLEY: Cynthia, everyone knows that a grilled tomato is a key part of the full English fry-up. Which really got standardized at this exact time, in the Edwardian era. In some ways, tomatoes were really the first vegetable that British people appreciated, outside of the potato of course.

GRABER: No comment. But Brits couldn’t get tomatoes in the winter, which was a bummer. Until the Italians ratcheted up their canning prowess to meet the demand. And so, within only a few years, the industry had basically switched from canning paste to canning whole tomatoes, and the canning industry in Italy as a whole grew, too.

TWILLEY: And although the Brits really kickstarted the Italian tomato canning industry, Italian-Americans hopped aboard soon after. Like Arthur said, they were merrily importing tomatoes from the homeland alongside all the cheeses and cured meats and olive oil they missed so much.

GRABER: But those tomatoes became harder to get ahold of in the 30s. First there were tariffs—we all know how great those are. And then the US was boycotting Italian products because of the fascist Italian government and their invasion of Ethiopia. And then Mussolini scaled down tomato production in the country in order to grow more grain so Italy could be self-sufficient.

JEFF LUNDQUIST: And the Italians had been shipping tomatoes to the United States and suddenly those imports were not coming in. And so there was this opportunity. And who better to fill that opportunity than those who knew about Italian tomatoes? The Italians.

TWILLEY: This is Jeff Lundquist, he’s a regional sales manager for Stanislaus. And seeing this demand, Italian Americans had started growing tomatoes to can them in Jersey and Pennsylvania, but also increasingly in California.

GRABER: Among those Italian-Americans was the family that started Stanislaus. But Stanislaus doesn’t sound Italian, and it’s not actually their name. Ralph and Edna Quartaroli started the company in 1942. At that point there was one more strike against Italy—it was part of the axis we were fighting in World War II.

LUNDQUIST: And having an Italian name in the United States was not the greatest thing at that time. So they saw that opportunity. They jumped into it, but they were nervous about having their names on the businesses. You know, everything was rationed during that time. And they were concerned that they would be last on the list to be able to buy equipment.

TWILLEY: So the Quartarolis named their new company after the county it was based in instead. Stanislaus County, California.

GRABER: At the time, their canned tomatoes were produced in a super hands-on manner, like all the canned tomatoes back then. It was mostly women and children working in the factory. They were doing things like coring the tomatoes and slipping skins off newly boiled tomatoes with their bare hands.

TWILLEY: Meanwhile, in the fields, a combination of midwestern Dust Bowl refugees and Mexican immigrants picked every single fruit by hand. During World War II, California growers complained about labor shortages, to the point that the US government launched something called the Bracero Program to bring in Mexican laborers on a temporary basis, to help get the harvests in.

RIOS: Before this was all picked by hand. Into wooden crates. Those wooden crates would be put into trailers, taken to the cannery, like, unloaded by hand and then dumped. So, I mean, that process just took a whole lot of time and it’s very labor intensive.

TWILLEY: This kind of work was called stoop labor, because it was so backbreaking. And the bracero program was sort of legendary for how exploitative it was. But most California tomato growers loved it because the braceros were a cheap, easily controlled, non-union labor force.

GRABER: But some people looked at how much labor it took to get the tomatoes from the field and then into the can, and they thought there had to be a better way. Mechanization would transform the tomato itself, and it had ripples throughout the entire United States. That’s coming up, after the break.

[BREAK]

TWILLEY: At this point in history, in the 1940s, the tomato was in kind of a pickle. Not a literal one, however delicious that might be, but more of an existential one.

GRABER: The tomato was weak, genetically speaking. They were domesticated in Mesoamerica from only a small number of tomato plants out there in the wild. And then only some of those plants were taken to Europe and bred further, which created even more of a genetic bottleneck. And then only some of those tomatoes made it to America.

ALEXANDER: That’s the kind of genomic pool that we’ve been working with here. Probably represents less than five percent of the total tomato genome.

TWILLEY: Fortunately one man—a kind of tomato Indiana Jones—was determined to turn things around. Meet Charley Rick.

ALEXANDER: Charley Rick was head of the wonderfully named Truck Crop Division at UC Davis. And he would go to South America every year, drag his family down there in his beat-up van. And he would look for specimens of tomatoes, or even relatives of tomato, that we didn’t have here.

GRABER: Charley brought back tomatoes from his adventures in South America, he grew them out at the university, and he looked for useful traits that he’d then breed into tomatoes here.

ALEXANDER: In fact, almost all of tomatoes you, you buy today have some genes that were brought back to America by Charley Rick.

TWILLEY: On one of Charley’s tomato collecting adventures he went to the Galapagos Islands, and he picked up seeds from a wild tomato there.

ALLEN: And he couldn’t get the seeds to germinate. He tried planting them in different kinds of soils.

ALEXANDER: He tried putting ’em through some finches, the ones that Darwin had written about, he still could not get them to germinate.

GRABER: Some seeds need to pass through an animal’s digestive tract for them to germinate. So it made sense that Charley thought that the Galapagos finches that Darwin made famous, maybe they’d get the tomato seeds going. But no.

ALEXANDER: Then he remembered that he had seen some Galapagos turtles wandering around the area where tomatoes were.

ALLEN: And he had a friend at the University of California in San Francisco who had some Galapagos turtles, a couple of them. And so the friend would feed the seeds to the turtles.

ALEXANDER: After about a month, because tortoises are, of course, notoriously slow in everything that they do. About a month later, he would send back the scat from the tortoise.

GRABER: Charley searched through the turtle poop to look for tomato seeds, but he couldn’t find them, and he wasn’t even sure which batch of poop had the seeds. So he got the idea that he’d ask the friend to feed the turtle dyed lettuce leaves at the same time as the tomato seeds. It worked: when that dye showed up in the poop, there were definitely seeds there too.

TWILLEY: And lo and behold, once these seeds had passed through the digestive system of a Galapagos turtle, they could finally be germinated.

ALLEN: And you know, this would just be an amusing—I mean, it is an amusing story. But also, these, these tomatoes that grew out of it contained this, this trait, which is called jointless pedicel. And what it is, is it’s something that allows the stem of the tomato to fall right off of the fruit. And this is key to making processing tomatoes.

GRABER: Almost every other tomato at the time had a joint in the stem not far from the fruit. It meant that when you picked the fruit, a little bit of stem would come off with it, and that was another thing that had to be removed in the canning process.

TWILLEY: It was also a poky thing that would stick into other tomatoes in the harvest bucket, and those holes would lead to rot. Basically: all bad.

GRABER: But the Galapagos tomato didn’t have that joint in the stem, and so the tomato would just come off cleanly right at the fruit.

TWILLEY: This jointless pedicel gene wasn’t something Charley was specifically looking for. But it was very handy, because one of his colleagues at UC Davis, this guy called Jack Hanna—he had decided he wanted to optimize the tomato harvest, and this was one of the issues he needed to fix.

ALLEN: He was Texas born, you know, farm kid who was just totally unsentimental about farming. And, you know, was all about efficiency. But he had this idea to create a harvestable, you know, mechanically harvestable tomato.

GRABER: At the time, nobody really took Jack seriously. Tomatoes were notoriously mushy things. You know, if you didn’t like a politician, you might throw a tomato at him, and it would splat. A hard tomato that could be picked up by a machine? That sounded totally ludicrous.

TWILLEY: But Jack was not a man to be deterred by other people’s lack of faith. He decided the problem needed to be tackled from two angles: somebody needed to invent a machine, but also, he needed to reinvent the tomato.

ALLEN: The tomato had to have a lot of very specific qualities.

GRABER: One of them was that it had to have that jointless gene, so only the fruit would come off the stem. Ideally, it also wouldn’t have a white core, because that was something canners had to cut out. And fortunately Charley Rick had found a tomato that was kind of oval-shaped that had no white core.

TWILLEY: The list goes on. An optimized tomato plant should have fruit that all ripened at the same time.

ALLEN: That’s ideal for processing because when you go through the field, you’re harvesting the whole plant. So you want as many of those tomatoes to be ripe as possible.

TWILLEY: Amazingly, the gene that made the tomatoes on a plant all ripen at the same time also had another extraordinarily useful effect. It made the tomato plant what is called determinate. Which means that rather than just growing and fruiting, and growing some more and fruiting some more, all season long—which means that you have to support the plant on a trellis. Instead these determinate plants just grow into a little bush, stop, and fruit.

ALLEN: And what the idea is, is that each shoot that goes off, flowers, produces a tomato, and then it stops growing. So you, they all grow out from the center stalk to more or less the same length.

GRABER: And finally, Jack needed a machine harvestable tomato to be hard enough that the mechanical harvester wouldn’t smush it. So he’d breed tomatoes he thought might be harder than usual, and he’d drop them.

ALLEN: Like he’d take them out in the field and drop them. And he, he, he would say, well, a good one would, you could drop twice before it broke. A really good one, you could drop three times.

TWILLEY: Meanwhile, to tackle the machine part of the mechanical harvesting problem, he worked with an engineer at Davis called Coby Lorenzen. Coby started out with a modified potato digger, which managed to harvest a very respectable 80 percent of the tomatoes in a field, but left them a single soggy muddy mass.

GRABER: Over the next decade, Coby and Jack and their colleagues developed all sorts of improvements. They went through 30 to 40 different versions of the harvester. Finally in 1959 a farmer agreed they could try out the latest version in his fields.

ALLEN: And they said, don’t invite anybody because this is just a prototype. And when they got there, the whole field was just full of all these academics and farmers and industry people. And they were all joking. And of course it made a huge mess. It made one big pile of like, tomato goop with mud in it, and the machine would break down, and the whole thing was just—you know, a mess.

TWILLEY: But Jack and Coby were determined to succeed, and they kept tweaking the machine, and they eventually got it to a point where only about a quarter of the tomatoes turned into goop during the harvest. Which was closer to being considered an acceptable loss. At least by some tomato growers.

GRABER: Including someone named Tillie Lewis. She was a pioneering businesswoman in the early to mid 1900s. She started off in the tomato business because she married a guy who was a wholesale grocery distributor, and he did a lot of work with imported food from Italy, like canned tomatoes.

TWILLEY: She thought the San Marzano tomatoes that the Italians were growing and canning tasted way better than what American farmers were growing. And then, when those tariffs we talked about came along in the 1930s, she saw an opportunity. Why not grow the good Italian tomatoes in California?

ALLEN: And her husband was like, nah.

GRABER: Experts at the Brooklyn Botanical Garden also told her this wouldn’t work, but she didn’t care. Tillie headed off to Italy, she met her husband’s connections in the canning business—she actually worked in a cannery for a while—and then she divorced the guy, and moved to Stockton in the Central Valley.

ALLEN: And then she partnered up with an Italian-American guy and they started growing San Marzano tomatoes, in California.

TWILLEY: His name was Florindo del Gaizo. His family ran one of the biggest tomato canneries in Naples, and he was apparently tall, dark, and handsome. There were rumors, but all we can say for sure is that Tillie and Florindo never married. Their names were combined only on a tomato can—their new company was called Flo-Till, from Florindo and Tillie.

GRABER: In any case, Florindo soon died and Tillie was left in charge of the company—and one of the reasons that her tomato canning company could more easily adopt the new harvesters was that she was already growing longer, thinner tomatoes and these were better suited to the machines. Most everyone else was growing big round tomatoes. And they couldn’t be bothered switching not only to a machine but to new tomatoes too.

ALLEN: And she invested and, and, you know, bought some of these machines. So she was very important for getting this off the ground.

GRABER: Tillie lived a fascinating life—she even invented some of the earliest diet foods, but for the rest of her story, you should go listen to our episode called “Sweet and Low Calorie,” about artificial sweeteners! She was a force of nature.

TWILLEY: Gradually, other tomato canners followed Tillie’s pioneering lead and got on board, especially once labor became a real issue after the end of the Bracero Program in 1964. That year, only a quarter of California’s tomatoes were harvested by a machine. But just two years later, it was 80 percent. By 1968, the hand harvest was over: canned tomatoes were basically all harvested by machine.

VOICEOVER: Modern industry in the field. The machine picker is a triumph of recent agricultural engineering.

GRABER: The machines work by digging into the dirt and scooping up the tomato plant. This is great if the fields are dry, and most of the tomato fields in California were irrigated, not rainfed, so that irrigation could be turned off.

ALLEN: But the disadvantages in the east are that, you know. It rains all the time.

TWILLEY: Before the mechanical harvester, there were plenty of tomato canning factories in Indiana, and Maryland, and New Jersey. After, nine out of every ten tomatoes grown for canning were grown in California.

GRABER: But that wasn’t the only impact. The machines were so expensive that only large farms could afford them. Within five years of the machines’ large-scale adoption, thousands of tomato growers went out of business. Only a few hundred remained, and tens of thousands of jobs were lost.

TWILLEY: Stanislaus is one of just a few big canning businesses in the Central Valley today, and they do the harvesting for their growers. We went out into the field to see the latest and greatest version of the mechanical harvester.

RIOS: As you can see here, this is a tomato harvester. We have about seven or eight that Stanislaus owns.

GRABER: We stood next to it, it is really really big, like as big as a school bus. It has all sorts of different kinds of machinery sticking out on either side and what looks like a massive conveyor belt slash escalator going up the entire front, next to the driver who’s sitting in a covered cab.

RIOS: I’ve tried driving one of these things once. Very terrifying. It is all… it’s a big machine.

TWILLEY: You’re not going to let us drive it?

RIOS: You could get on it. I don’t know if—[LAUGHING] I don’t know if I’m going to let you drive it.

TWILLEY: Juan is a wise man. But he did let us climb aboard and admire the machine from there. At the bottom of that massive conveyor belt there’s kind of a combo digger-slicer.

RIOS: And really what it’s doing is skimming about like, the first inch or two of, of the top soil. And it’s pinching that plant off. And when that plant gets pinched off, it goes onto this belt right here, hugged by this belt on top. And it’s basically, to me, it always looks like a carpet of tomato plant going up.

GRABER: The whole plants roll up the conveyor belt, and a lot of the dirt falls off them. As the plants are being jostled and shaken around, this helps dislodge the tomatoes from the vine, and they roll onto a different belt.

RIOS: And that’s where you get like the first introduction of technology that’s changed quite a bit. And this is like laser eye sorters. And these can be set up to see certain color. And certain color actually activates the fingers that are down here.

[CLACKING, POPCORN-LIKE SOUND]

RIOS: You can hear that sound.

[MORE CLACKING]

RIOS: When you hear that. Really what it is, is it’s seeing red. And it’s set up to see red. So as soon as it does, it’s able to ignite those fingers with little air pressure and it’ll kick the red tomatoes back in.

TWILLEY: Anything that’s not red, like all the green parts of the plant and dirt and green tomatoes—that gets shaken down into a shredder. And then a vacuum hose sucks up any loose debris.

RIOS: And it’ll shoot that into the shredder as well, and then out the back. Never want to stand behind a tomato machine while it’s moving.

GRABER: Juan has learned this the hard way.

RIOS: Oh, it’s a game for some of these guys, sometimes. Whenever I’m driving by them or something like that, they’re just like, oh, lemme turn it on. And you get painted green.

TWILLEY: The tomatoes pass along the length of this machine, and along the way there a couple more sorters, all kicking out anything that isn’t a perfect red tomato. All these lasers and scanners, they weren’t on Jack Hanna and Coby Lorenzen’s original machine.

RIOS: Before, there would be about 14 people on the machine. And what they were doing is they would be going even slower, but they were hand sorting everything. So that way you’re still getting only red into the tub. But it was all manual labor.

TWILLEY: Still less labor than harvesting by hand, but a lot more than today!

GRABER: Juan explained how this all works while the harvester was idle because once it gets going it’s really loud. We were standing next to the sorter when he told the driver to start up the engine and get digging.

[HORN BEEP]

TWILLEY: And just like that, the machine rumbled off, sucking up all the plants in its path, and all the ripe red tomatoes came rolling down the belts beside us. We have video on our socials, it’s quite astonishing honestly.

RIOS: Even watching it with the naked eye, you barely see it going on. But when you watch it in slow motion, and you see the little lasers kicking everything off. And anything that’s not a red ripe tomato is booted out right in the field.

TWILLEY: I could have honestly stood there all day. Watching this huge machine lumber up and down the rows of tomatoes, sucking up entire plants, pooping out dirt and leaves, and raining down beautiful perfect ruby red tomatoes into huge bins on a truck that follows along. It was mesmerizing.

GRABER: The machine itself is, as Nicky, said astonishing. And then I was also shocked to learn that during the season, which is only a little more than two months—these machines are running all the time.

RIOS: The machine runs 24 hours, seven days a week, just like the cannery does. It’s intense. The only break these machines really get is kind of cleaning up before shift change.

TWILLEY: All of this sounds extremely industrial and as though efficiency has triumphed yet again over taste. That’s the story of fresh tomatoes, for sure. But it’s not the story of canned ones! Why canned tomatoes are actually the greatest and tastiest pantry staple, and how to make sure you’re getting the most delicious ones, after the break.

[BREAK]

GRABER: We told you that Jack Hanna and other people at the time and since then who’ve been breeding the perfect tomatoes for canning had some very specific tomato features in mind, and none of them were about flavor. But that’s not the whole picture. Tom Cortopassi—he’s the president of Stanislaus—he told us what his breeders focus on.

TOM CORTOPASSI: Well, first off, you know, it has to be able to handle that harvester. Right? So it has to have enough firmness. They also, you notice they kind of all ripen at once.

TWILLEY: So far, so similar to Jack Hanna. But that’s not all canned tomato breeders are looking for.

CORTOPASSI: From a tomato standpoint, you know, the varieties that we choose have a lot of flavor. A nice balance of sugar and acid. That’s what gives you that, you know, when you bite in a tomato, you get both. It’s like any good food. It’s balanced.

TWILLEY: Of course, Tom would say his company’s tomatoes are flavorful. But there’s only one way to verify that.

RIOS: You guys want to take a bite?

TWILLEY: Yeah.

GRABER: Yes, of course.

RIOS: Have that here. Lemme clean one up for you.

TWILLEY: Okay the first thing to point out here is that all canning tomatoes are harvested ripe so they’re at their full flavor potential. That helps

GRABER: And Juan had brought a little salt for us, that also helps…

GRABER: I love that you brought salt for us.

TWILLEY: Perfect.

RIOS: Here’s a little piece.

TWILLEY: Thank you.

TWILLEY: Mmmmm.

GRABER: Mmm. Mmm. That’s really good. Yum.

TWILLEY: It still had that heat from the field. It was ripe, it was juicy, it was a good tomato. It was a little firmer than the ones I grow or pick up at the farmers market.

GRABER: That’s because, as we said, they’re bred to be able to make it through mechanical harvesting without getting smushed. So I wouldn’t necessarily choose it for my salads.

TWILLEY: But it still tasted like a tomato. Much more tomatoey than the fresh eating tomatoes you buy at the store out of season.

GRABER: In a way, canned tomatoes got lucky. We mentioned in the fresh tomato episode this summer that flavor accidentally got bred out of Florida tomatoes, as they were being bred to be hard and shippable and something that could be picked green and ripened later.

TWILLEY: That never happened to the varieties of tomatoes that are grown for canning. They were intensively bred to be machine harvestable, but the flavor genes came along for the ride. And honestly, we are all grateful for that stroke of luck.

GRABER: Stanislaus is a canning company that only sells to other companies, you can’t buy their products at the grocery store, and Jeff told us the main way they try to distinguish themselves is taste.

LUNDQUIST: Our customers are restaurateurs. We’re trying to help the mom and pop, onesie-twosie, restaurant owner to have superior flavor over chain operations that can have price advantage. So we want to give them flavor advantage. And that’s why flavor is so important to us.

TWILLEY: Lots of things go into flavor, including the tomato variety and how it’s grown, but Stanislaus’ big edge is to do with how they process the tomatoes. You, like me, have probably eaten canned tomatoes and tomato sauces your whole life without ever realizing there’s a big divide in the world of canned tomato products—and it’s to do with how they’re processed.

CORTOPASSI: Three out of every four tomatoes that get harvested in California make it to industrial paste, you know, which is, you know, kind of tomato sludge. And they take that paste and they make other—sauces, barbecue sauce, soups, things like that.

RIOS: We, we do, no pa—no paste. Zero. So it’s all just fresh pack tomatoes here.

TWILLEY: There’s industrial paste, and there’s fresh pack, and from the way Tom and Juan talked about it, it’s pretty much a case of never the twain shall meet.

GRABER: So assuming you are like us and these terms are new to you, let’s start with paste processing. Jeff told us the first part is the same, the harvest—

LUNDQUIST: And then you’re going to bring the product into the plant and you’re going to cut it up and juice it. And you’re going to take that juice and you’re going to evaporate it until you just have a very, very thick, thick paste. Thicker than you would buy in in the store. And they’re going to put that paste in a big tote, and they’re going to set it aside.

TWILLEY: In the 1970s, a scientist at Purdue whose family worked in the tomato canning business invented this aseptic storage system. He figured out that if you coated steel tanks with epoxy resin, and sterilized all your equipment, and filled any air gaps with nitrogen gas, you could store tomato paste at room temperature for months and months. He won the World Food Prize for this breakthrough—and ended up revolutionizing the juice industry as well as the canned tomato business.

GRABER: Jeff told us that today, companies will put their tomato paste in 300 gallon aseptic bags that are stored in plastic bulk storage boxes.

LUNDQUIST: Then what they will do is when the season is over, they will bring that product back into the plant. And they will heat it again, and then they will add water to it, and they will make a sauce.

GRABER: Like pizza sauce, pasta sauce, or ketchup, soup, barbecue sauce—whatever tomato product a company wants to make.

VOICEOVER: Heinz use tomatoes for tomato soup, tomato ketchup, the famous source for baked beans and also for spaghetti.

LUNDQUIST: Like I said, 75% of, of the tomatoes are done that way.

VOICEOVER: The main bulk of the tomatoes is converted into tomato puree. Lovely stuff.

TWILLEY: This is the split in the canning industry. The other side, the side Stanislaus is on, they do something called fresh pack. They don’t make paste and store it and reconstitute it later in the year. They just put the tomatoes in the can after harvest.

GRABER: A fresh pack plant has to be big enough to process all the tomatoes they want to package in that short window of time those tomatoes are ripe. And then that whole huge factory sits idle the entire rest of the year. That’s why these kinds of tomatoes are more expensive.

TWILLEY: But this process also has an impact on flavor.

LUNDQUIST: And so it has one cook. Versus most industry is doing two cooks.

GRABER: That one cook—that’s because all canned tomatoes have to be cooked for a certain amount of time to kill off any pathogens and sterilize them, that way they’ll stay safe in the can for a really long time. Paste makers cook their tomatoes twice, as Jeff said, and they cook them for a LONG time. That really changes the flavor of the tomatoes. But the folks at Stanislaus do it differently.

LUNDQUIST: A very important formula for us is that time and temperature are the enemy of fresh tomato flavor. So we’re always trying to manage that to reduce the time, reduce the temperature.

TWILLEY: What that means is that the tomatoes go from that monster machine in the field to the plant in no more than a couple of hours, and then they try to get them out of the plant, in a can, in the next four hours. So six hours total, from growing in the field to sitting in a can. We followed them over to the plant to see what happened next.

LUNDQUIST: So we’re entering the plant.

GRABER: Oh, it smells amazing. Now I’m getting hungry.

TWILLEY: You can smell the tomato!

GRABER: There were conveyor belts of tomatoes all around us.

LUNDQUIST: So it’s just two rivers of red going down to this escalator at the end, where they’re climbing up into our plant.

TWILLEY: I absolutely love the rollercoaster. They’re going up, they’re going down, they’re going across, they’re going round.

GRABER: Luckily, not quite as fast as most roller coasters are.

TWILLEY: The tomatoes get thoroughly washed, of course, and there are various scanners and humans doing quality control at all points. But the first stop for most of the tomatoes is this incredibly clever machine that uses steam and rubber fingers to get the skin off.

GRABER: We can see the tiny like little bits of tomato skin coming off there.

TWILLEY: It smells like cooked tomato now. And it’s so clever. They’re like just gently being rubbed by this, like—these rubbery fingers.

GRABER: And then we watched the tomatoes come out the other end after all the skin had been removed.

[MACHINE SOUNDS]

GRABER: Oh my gosh!

TWILLEY: There they are, the naked skinless tomatoes! They look like naked skinless tomatoes.

GRABER: But like beautifully perfect naked, skinless tomatoes. Like surprisingly perfect.

GRABER: Stanislaus makes a bunch of different canned tomato products. They package those beautiful tomatoes whole, in a bunch of tomato juice and sauce made from less than perfect looking tomatoes. They sell cans of crushed tomatoes. They even make their own sauces—but definitely not reconstituted from paste.

TWILLEY: At this point in our tomato journey, it felt like time to eat again. We’d tried the tomato in the field, it was delicious. But how about once it was in the can? Could we really taste that fresh pack difference?

GRABER: Stanislaus has a company kitchen on site and a chef who works there, and the chef had prepared a number of different dishes for us. One of them was a plate that had just one perfect canned tomato with some mozzarella, basil, and olive oil. I’d never seen a mini caprese salad made of canned tomatoes before.

TWILLEY: I had not either, and frankly, I admired the chutzpah—I mean, this is a dish supposed to showcase the most perfect summer tomatoes.

TWILLEY: All right, I’m going to, I mean, I’m going to start with the tomato ’cause that’s the main event here. It’s got a little bit of olive oil and a little bit of basil. …Mmm. That is unnaturally delicious. It is so, so pure tomato.

GRABER: I’m also really impressed with the texture of it. Just even cutting into it. It has a little give, but you can cut it really easily. It’s like a really lovely textured tomato.

TWILLEY: And it doesn’t have any of that solid core that you can get. It’s a—just all tomato, all the way through. Pure red. The color is intense.

GRABER: It’s very beautiful. Here we go. [CHEWING] Mmm. That is a delicious tomato.

TWILLEY: This was actually kind of mind-blowing: a canned tomato, served where you would normally have a fresh one, and it was just as if not more delicious.

GRABER: They served us their sauces in a few different dishes, too, and those were also super delicious. Now here’s where we have to disappoint you listeners, though, because—we did tell you, but here’s a reminder—Stanislaus only sells to restaurants and food companies. Their cans are a full gallon each can, more than 6 pounds of tomatoes in there. Whereas a large can in the store is about just under 2 pounds. Sorry!

TWILLEY: I am considering doing some kind of deal with my neighborhood pizza restaurant. That said, honestly, the canned tomatoes in the store are all pretty good.

GRABER: But for people who are looking to get the very most delicious canned tomatoes, the advice you always hear is buy San Marzano tomatoes, they’re the best.

CORTOPASSI: The San Marzano is kind of a… It is pretty mythical.

GRABER: The story behind the San Marzano goes like this. As we discussed in our tomato episode this summer, tomatoes in general took a while to catch on in Italy, but when they did, they were huge hits.

TWILLEY: But as Italians started canning whole tomatoes to supply the British market, they started planting a new variety. It was a cross between two traditional varieties that had been developed up north, near Parma. This new variety was the legendary San Marzano of tradition—which means it’s really only a century old.

GRABER: A tomato canner who lived up north brought the seeds of this hybrid to southern Italy for a few reasons—the volcanic soils near Vesuvius were incredibly rich, it’s sunny, it’s a great spot for tomatoes. They do really well there. And some farmers were willing to give these new tomatoes a try.

TWILLEY: Within a couple of years, the San Marzano was *the* tomato, everyone in the region was growing it, it was being exported and people like Tillie Lewis were falling in love with it. It was the bedrock of Italy’s tomato canning industry, they saw it as red gold.

GRABER: For a few decades, things were going swimmingly. And then disaster struck. Arthur told us the story.

ALLEN: What happened in Italy was that in the sixties and seventies, the San Marzano just became subject to all of these molds and wilts and, and critters. And it was going to go extinct.

TWILLEY: Time for a new tomato to come to the rescue: the authentically Italian sounding Roma.

ALLEN: The Roma was, I mean, it was actually developed in the US. And so, yeah, I mean, it sounds like it—what could be more Italian?

GRABER: Seriously. But no, it was developed at a USDA facility in Maryland. The Roma does have some San Marzano among its many tomato parents, but other tomatoes were involved too, and it was bred to be resistant to all those molds and wilts.

TWILLEY: So Italian growers mostly switched to that. Today, Stanislaus and most other canners have moved on to even newer hybrids, though even those have both Romas and San Marzanos in their ancestry.

GRABER: In the 1990s, the Slow Food movement, it was founded in Italy just a few years before, they wanted to bring the original San Marzanos back. But when they went looking for San Marzanos being grown near Naples, they found twenty different kinds of tomatoes all being called San Marzano.

TWILLEY: What had happened, since the days of Brits enjoying San Marzanos with their fried breakfasts and Tillie importing them to the US—what had happened is that Italian tomato growers had let their tomato plants have lots of indiscriminate sex.

GRABER: Nobody was monitoring the purity of the San Marzano line. Some San Marzanos survived the bugs and wilts and likely either accidentally or on purpose were crossbred with other local tomatoes, and so people were growing those and calling them all San Marzanos. Which was a problem for the Slow Food people.

TWILLEY: Slow Food ended up just choosing two of the many so-called San Marzanos being grown, and calling those the official San Marzano tomato. And the growers in the region also got something called a protected designation of origin—a PDO, or DOP depending on which language you’re speaking. That means that all canned tomatoes labeled San Marzano DOP have to be one of those two varietals, grown in this one specific region near Naples.

GRABER: But even if you buy a can of tomatoes labeled San Marzano DOP, they might not actually be one of those two varieties or grown in that region. For one, there’s only a tiny tiny amount of land dedicated to San Marzanos, and so there’s way more demand than supply. That creates an incentive for fraud.

CORTOPASSI: There’s not that many. There are some, that come from that region in Italy. We don’t think many come to this country. Because why would they? They’re going to keep ’em in Italy.

TWILLEY: The other issue is that if you’re buying San Marzano DOP tomatoes in the US, well, it’s not actually fraud to label them DOP even if they’re not grown in the region, because the US does not honor European DOP regulations.

GRABER: So it’s certainly possible that those San Marzanos you buy at the store might not be San Marzanos according to the letter of the DOP. It’s really impossible to know, but they still might be delicious!

TWILLEY: So if looking for the label San Marzano isn’t going to guarantee peak deliciousness, what should you look for? What’s a winter tomato lover to do?

GRABER: First off, you want to buy whole canned tomatoes if possible. That way your tomatoes definitely won’t be reconstituted from paste.

CORTOPASSI: If you see a can and it’s—you open it up and they’re whole? Yeah, that’s a, it’s, there’s no other way of doing it. You can’t preserve the tomato and then repack it whole. So that’s the one item when it’s—you know, when it’s the actual whole tomato, you know.

GRABER: But crushed and diced can be even more convenient to use than whole ones in a can, how about those?

LUNDQUIST: As you cut up those tomatoes and you create different products, you’re getting further and further away from the garden. Diced tomatoes is obviously going to be a tomato that doesn’t need to have the visual aspect that a whole peeled tomato—’cause it can, you can just cut it up and you don’t know that, you know, it didn’t look great. You’re also going to use a fair amount of calcium chloride to firm that tomato up. Because, the tomato when it’s cut in those little squares is not going to retain that shape on its own.

TWILLEY: Calcium chloride is a kind of salt, it’s a common food additive. You’ll often find it in cans of beans too.

LUNDQUIST: So they put that calcium chloride chloride in there and that’ll firm it up and give it that identity. Some people can taste that. And it’s, it’s kind of a chalky taste, if you can pick it up. That would not have the same quality and sweetness that you would get with a whole peeled tomato.

GRABER: Crushed and ground tomatoes don’t have calcium chloride added, they don’t need it.

TWILLEY: But they could be reconstituted from paste—some are.

GRABER: For sauces, you have to look at the ingredient list.

CORTOPASSI: If you go to the grocery store and you look at a sauce and it says like, tomato puree, and then parentheses, paste and water. Then that means it was remanufactured. Most of everything on the grocery store shelf is that way. Not everything.

GRABER: I didn’t know to look for this before we reported this episode, but I was happy to see that my favorite sauce, basically the only one we buy, it’s clear that it’s not reconstituted. That might be why I like it so much.

TWILLEY: But honestly, even the cheapest, most basic, reconstituted-from-paste canned tomato product is still a good thing. And that’s because, like we said, canning tomatoes never had the flavor bred out of them and they’re allowed to ripen before they’re harvested. And that is why we love them!

ALLEN: I think a can of tomatoes is one of the most underrated, cheap products you can buy.

TWILLEY: Amen to that.

GRABER: Honestly, if there’s one tip we could give you for winter cooking, it’s to always keep canned tomatoes around! We are not being paid by Big Tomato, we do genuinely believe that they’re the greatest.

[MUSIC]

TWILLEY: Thanks this episode to the folks at Stanislaus Food Products: Juan Rios, Tom Cortopassi, Jeff Lundquist, and Peaches Brady, you can find their product at all the best pizza restaurants. And thanks to Alec Wasson for connecting us to them.

GRABER: Thanks also to Arthur Allen and Bill Alexander, we have links to their books on our website, gastropod.com. Thanks also to our fantastic producer, Claudia Geib. We’ll be back in a couple of weeks, till then!