Espresso Technology

James Harper

So, a few months back, I took a sip of a really, really good espresso.

It was very rich, creamy, there was a layer of crema, like that golden foam floating on top, it sparkled with a bit of acidity and chocolate notes, just sumptuous.

And I began to wonder, who woke up one day and thought, you know what we should do?

Let's make a really short, intense coffee by grinding the coffee super fine and pushing the water through with a lot of pressure.

That is how you make a good espresso.

But who came up with that idea?

And here's the thing, we do know some of the origins of espresso.

We know who, and why, and how, but what we don't have is the colour, you know, the good story.

So let me give you a blend of what I imagine might be the origin story of espresso.

So, one fine summer day, back in the 1880s, a man with a wonderfully coiffed white moustache and beard, strides into a hotel cafe, the Gran Cafe Ligure.

Now let me be clear, he's not here to enjoy a coffee, he owns the place.

Professor Jonathan Morris

Moriondo is the owner of various hotels and establishments in Turin.

James Harper

This is Professor Jonathan Morris, a coffee historian and the co-host of our series, A History of Coffee, link in the show notes.

Now I would imagine that Moriondo is very proud of his grand hotel cafe.

Possibly in the corner is a phonograph playing Avent the Opera.

It's like a really early version of NLP player.

This is cutting edge technology.

And he also feels very proud because his cafe is in the same city where the King of Italy is from, the grand northern city of Turin, sandwiched between the Alps and the Mediterranean.

Moriondo walks into the middle of the tables, stops and looks around, and he spots a problem.

One of his guests is complaining to the manager.

Look, I have a busy day and I wanted a quick coffee, you know, to get me going.

It's been 10 minutes and nothing's arrived.

I'm going to be late for my first appointment now.

The manager is very apologetic.

He then strides into the kitchen and shouts at one of his staff.

Where's the coffee the gentleman ordered?

And his staff reply meekly.

Sorry, sir, I just need a couple more minutes because I'm just halfway through pouring the water.

Now, back in the 1880s, espresso machines hadn't been invented yet.

So when one of Moriondo's patrons orders a coffee, they would have been probably given a filter over a cup.

And as you know, making a filter coffee can take time.

Professor Jonathan Morris

And Moriondo, he thinks to himself, I don't want to wait four minutes to make a coffee for my clients.

I want to be able to serve them quicker.

James Harper

And what he does next leads a number of espresso machine engineers to name him the Father of Espresso.

The Father of Espresso.

It's a grand title.

James Harper

OK, so here we have Angelo Moriondo.

James Harper

But how good was this machine, really?

And he's created this contraption.

And a few months back, I visited the Museo delle Macchine per Caffè, MUMAC, part of the Cimbali Group, to look at a replica of Moriondo's machine.

There's a link to this machine and all the machines we're going to talk about in the show notes.

It looks like a boiler, knit with bits on the side.

It looks like a hot water boiler.

You might find at a wedding.

But it's got all these gnarly metal bits and pieces hanging off from the side.

And let me be frank, as an espresso machine, this thing is terrible.

And I'll explain in a second why it's a terrible espresso machine.

But as far as our white mustachioed Moriondo is concerned, it fixed his speed problem.

Anna Cento, the curator at the MUMAC Museum, explained to me how this machine makes coffee faster.

Anna Cento

So the boiler makes the steam.

The steam goes to the water and the water goes to the coffee.

James Harper

Moriondo invented what is basically a hot water boiler.

But the steam it creates would push hot water through half a kilo of ground coffee.

And then it would just sit in an urn hanging off this machine.

And when someone orders a coffee, you just decant it into a cup.

So that's the plus side.

Get an order for a coffee.

Coffee.

Turn the lever.

Out pour some of that pre-made coffee.

Put the cup in front of the customer.

But in almost every other way, this was a terrible espresso machine.

You know, no shade to Moriondo.

What he created with the technology at the time, it's ingenious.

But I would not use this machine to make espresso.

Not in a million years.

Anna Cento

So it was like actually not yet an espresso coffee machine.

James Harper

For one, the coffee it made.

It wasn't even espresso.

It made something that might have tasted closer to a filter coffee.

No crema.

No luscious mouthfeel.

And that actually might be the reason Moriondo referred to the coffee his machines made as caffè instantaneo.

Instantly made coffee.

Rather than espresso coffee.

Oh, and it might also have tasted pretty stale.

Because up to 50 coffees could be made at once.

And then they'd just sit around in an urn waiting to be decanted.

The coffees might have tasted oxidized, thin, papery.

James Harper

I guess we can't see where we can actually put the coffee into the system.

James Harper

So this machine made a very disappointing, quote-unquote, espresso.

But it also was pretty poor on usability.

Anna Cento

The coffee was inside there.

James Harper

It's quite hard to get out.

You have to undo the screws, open a lever, and then take the whole thing off.

James Harper

To make a new batch of coffee, you had to open levers, undo screws, touch hot metal components.

Just a nightmare.

And when I saw Moriondo's machine, I, for the first time, realized, oh my goodness, we have come a long, long way when it comes to making that delicious, creamy, mouthwatering espresso.

And that is the journey I want to take you on today.

It is the story of how espresso machine technology developed these last 150 years.

Things are going to get a bit...

Things are going to get a bit bloody.

Hylan Joseph

My hands looked like I was out of a serial killer horror movie.

James Harper

And there are moments in this story where I'm just flabbergasted at the ingenuity of engineers.

Especially when I visit the manufacturers of a fully automatic espresso machine.

Eversys, the sponsor of this episode.

That, at the push of a button, make an espresso as tasty as a good barista.

And it's a story of how a technological solution creates its own problems that require their own solutions.

And the cycle keeps continuing.

And they develop in ways that Moriondo himself could not possibly have imagined.

And it really gets you wondering, what is the perfect espresso machine?

How much further can we go?

And this is The Science of Coffee.

A spin-off series from my documentary podcast Filter Stories.

And a journey into coffee's hidden microscopic secrets.

So, it's the early 20th century, 1905.

The Wright brothers emitted an airplane that took off and landed.

Electricity is now surging its way into cities.

And the streets are full of horses.

Professor Jonathan Morris

And this, James, my friend, is the first commercial espresso machine.

James Harper

And in the MUMAK Espresso Museum, Jonathan and I stand in front of the first commercial espresso machine.

What Moriondo made was never made commercially.

But these sorts of espresso machines, made back in the early 20th century, made their way into hotels and bars across Italy.

And, to my mind, they look like fire hydrants.

These fire hydrant-looking espresso machines, they are gorgeous.

Shiny, ornate embellishments like leaves and ribbons.

And on top of many of these machines stood a proud metal eagle, wings outstretched.

But let's cut to the chase.

How good are they as espresso machines?

James Harper

So, what was wrong with Moriondo's machine that this thing fixed?

James Harper

So, one of the big problems with Moriondo's machine was the fact that the coffee probably tasted quite stale.

These machines fixed that.

Professor Jonathan Morris

Well, have a look at it.

This thing's got portafilters on it.

That's the huge jump.

James Harper

This machine had a portafilter.

And you know what a portafilter is.

It's the handle that holds the ground coffee that you slot into an espresso machine.

And now, coffees could be made fresh to order.

When you get an order for coffee, you put coffee powder into the portafilter, lock it into the group head, the machine, and out comes freshly brewed coffee that you immediately serve to the customer.

But as quote-unquote espresso machines, how good are they, really?

And as far as I'm concerned, they are not good at all.

And the first very serious problem is that these machines could be extremely dangerous.

James Harper

Espresso, pepe or de?

James Harper

Let me give you a day in the life of the person making the coffee.

And not just any day in their life.

Perhaps the worst day in their life.

Imagine a very chaotic day.

One of your customers at the bar is complaining about the public transportation.

And five minutes ago, the owner was having a go at you because your tie wasn't straight.

Oh, and then a delivery person walks through the door and they need a signature.

And just as you're about to put your pen to paper...

Anna Cento

About the explosion of a coffee machine.

James Harper

Oh, wow, this is amazing.

Anna Cento

This was a real Italian old magazine.

And this was a real news that happened in this period.

And in fact...

James Harper

Annacento shows me an image from a 1940s Italian newspaper at the Mumac Espresso Museum.

James Harper

This is extraordinary.

So this image, I mean, you have a bar and all the patrons around it, you know, wearing, you know, suits and ties.

And then this espresso machine, which is basically like a fire hydrant, it rips from the middle.

And you have steam and pressure and shrapnel flying in all directions.

You have people covering their eyes.

You have people falling over, you know.

And the barista, the poor barista gets it right in the neck.

He is like...

Because behind him are all the glass bottles, which are also exploding.

And it also says in his article, the barista was pretty badly hurt.

Professor Jonathan Morris

And the bottles and the glass go into him.

Yeah.

And they're all over the place.

Wow.

Yeah.

James Harper

Now, I was curious.

What was inside these espresso machines that could explode?

Can we, um, can we open the lid?

And I got my answer a few days later when I was at another espresso machine museum, the Ranciglio Officina 1926, a museum run by Ranciglio, the espresso machine manufacturers.

What year did this machine come out?

1927.

Wowza.

And they had their own Ranciglio version of this fire hydrant looking machine.

And I asked Giorgio Ranciglio, the former president of the company, whether I could take a look inside to see for myself what was exploding.

Professor Jonathan Morris

We try gently lifting the lid, but it doesn't budge.

You are such a destructive person.

You're not normally allowed to do this.

Jonathan Morris was not amused.

We are.

James Harper

But it works.

It works.

James Harper

Giorgio Ranciglio gets a paper knife, gently undoes the screws on the side.

James Harper

Here we go.

Oh my god.

Up.

James Harper

And lifts off the lid.

Giorgio Rancilio

OK.

Wow.

It is a kind of circuit that heats the water.

OK.

James Harper

So explain to me what the hell is going on.

Winston Churchill

Yeah, it's different.

Just a little bit difficult to understand.

James Harper

Let me show you how this machine works.

By pretending we are a droplet of Milan tap water.

And why you could almost kill a barista.

OK, so the water comes in from the side, from the bottom, right?

It goes up into...

So you're pushed from the mains, the water pipes, through an inlet tube.

It starts swirling around in a brass cylinder in the middle of this espresso machine.

Basically a kettle.

This is like a kettle, right?

James Harper

A mini kettle.

James Harper

It's like a mini kettle.

So you're a droplet of water.

You're swirling around in this brass container.

However, there's a heating element that's giving you energy.

And you're moving around faster and faster.

And then eventually you break free from all your neighboring water molecules and turn into a gas.

And as you're flying around in the air, you keep smashing into and bouncing off the metal container.

You hit in the side of this metal container.

That is what we measure as pressure.

And the pressure builds and builds.

How much pressure is in the chamber?

Approximately 1.5 bar.

And as you probably know, one bar of pressure is what we experience when we're at sea level.

So this boiler has 50% more pressure than what we feel going about our day.

But the reason these machines are so explosive is because you as the barista have to keep an eye on the pressure in the boiler.

Now, you release some of the pressure every time you make a coffee.

Because by turning a valve, the steam condenses into water and is pushed through the bed of coffee to make your espresso.

But if you don't make coffees for a long time, the pressure just builds and builds and builds.

And if you don't want this whole thing exploding on you, you have to release a valve occasionally on the side of the machine.

And that's why the barista actually wasn't called a barista.

Silvia Bartoloni

That was not even called barista, it was called machinist.

James Harper

A machinist.

Silvia Bartoloni

Yeah, because it was with the same idea, it could drive a train or could handle an espresso machine.

James Harper

It was a technician, not a barista.

James Harper

And this, by the way, is Silvia Bartoloni, guest relations manager at the third espresso machine museum I visited, l'Accademia del Caffè Espresso, half an hour outside of Florence, run by La Marzocco.

So these early boilers were dangerous.

And that's not the only reason.

These are frankly terrible espresso machines.

Professor Jonathan Morris

Because purely from the point of view of the espresso, quite a lot of people weren't happy with the quality of coffee by the thirties that was being produced by machines.

These were bad espressos.

James Harper

And that's because these espressos were brewed using super hot steam.

This is not water, this is steam.

Exactly.

When you make coffee with super hot water, and steam is by definition above the boiling point of water, the water is extracting a lot from the coffee.

And if you go back to episode two of this series on coffee extraction, you know that a highly extracted coffee can be very strong, very bitter.

The other thing is that the espresso doesn't resemble what an espresso looks like today at all.

It's like more similar to the mocha.

Giorgio Arantillio says it tastes more like, you know, the Italian stovetop coffee that Italians make in their kitchens.

It's nowhere near as deep and luscious as an espresso.

And there's no crema.

Winston Churchill

The German war is at an end.

Today is victory in Europe's day.

James Harper

So fast forwarding a couple of decades.

We're now in the late forties, rolling into the fifties.

The Second World War has come and gone.

The iconic Italian scooters, the Vespa, are hitting the streets.

American rock and roll is sweeping across Europe.

Professor Jonathan Morris

So listen, we've walked into the next room.

And espresso machines take a giant step forward.

Totally revolutionary comes out and you're standing next to it.

And that is the Gaggia Originale, the Gaggia Classico.

James Harper

Now, finally, we're getting somewhere with these espresso machines.

For the first time, we have a machine that makes what I today would consider an espresso.

Rich and creamy, sumptuous.

And most importantly, for the first time, we have crema on the coffee.

Professor Jonathan Morris

This machine produced that dark, velvety foam that floats on top of an espresso.

Crema.

So when this started, they actually called it crema cafe, cream coffee, to distinguish it from what was being made before as espresso.

So there's this whole new naming of the drink.

James Harper

What had changed to now create crema, was that the coffee was now being brewed in a completely different way.

Let me show you how.

So at the Moomak Espresso Museum, they had one of these vintage espresso machines produced by Gaggia that now made crema.

And it doesn't look a million miles away from a modern espresso machine, except for two key differences.

Its styling, and the rods sticking out on top of it.

Professor Jonathan Morris

So regarding its styling, Anna Cento, Jonathan and I actually had a debate as to whether it was more cinema curtain, or American jukebox.

James Harper

I've put a link in the show notes so you can decide for yourself.

But the most important difference is what is protruding out the top of these machines.

Half meter long handles are sticking out the top.

So let me explain how these levers produced a delicious coffee with cadena.

You're a barista.

Get an order for a coffee.

Get the portafilter.

Fill it with brown coffee.

Lock it in the group head.

And then you pull down the lever.

By pulling this lever down, you compress the spring that's sitting above the coffee.

Water rushes in.

Then you let go of the lever, and the spring tries to uncoil, but there's water in the way.

So it pushes this water slowly through the bed of coffee, and out comes thick, rich espresso.

The addition of a lever has given us a lot of pressure.

Professor Jonathan Morris

Basically what it does is rack up the pressure massively to over the course of a delivery between 3 to 12 bars.

James Harper

Much more than the 1.5 bars we had in the fire hydrants of earlier.

But there's more to it.

The water that's being used is at 93 degrees.

Professor Jonathan Morris

We've got rid of the steam.

And that means we're not doing all the bad things that the steam does.

Burn the coffee, etc.

But also a major, major difference.

James Harper

Because these levers create so much more pressure, we can grind our coffee powder much, much finer.

This helps to create those rich flavors of espresso we love so much.

And it also is responsible for the crema.

Now, the science of the formation of crema is quite fascinating, and I'll probably cover it in depth in a future episode.

For now, what you need to know is that when you grind coffee fine enough, and you have enough pressure, crema is formed.

And fun fact, the crema is actually a foam.

And a good foam needs surfactants.

And in the next episode on latte foam, I explain more in depth what surfactants are and how they work.

And so, by the late 40s, we finally have machines which create good espresso.

However, they are far from perfect.

Very far, indeed.

For one, it was difficult to get a consistent brewing temperature.

So, you know, your shots could be occasionally a bit sour.

But to me, that's a minor problem compared to this machine's biggest liability.

Hylan Joseph

It's 200 pounds of pressure.

It's like getting a punch.

It's like getting punched.

I mean, prepare yourself for a horror story experienced for real by this man.

I am Hyland Joseph.

I am West Coast Operations Manager for Espresso Partners.

I've been in coffee since 1982.

James Harper

Hyland is also one of the founders of the Coffee Technicians Guild.

But the reason I spoke with him is because he was a barista for a long time.

I'd love to know.

So, you're a barista in the early 80s.

James Harper

What kind of espresso machines were you using?

Hylan Joseph

My very first espresso machine that I worked on was a Gazia piston machine.

Pulled down piston type machine.

James Harper

No way!

Hyland began his barista career using these sorts of lever machines.

Hylan Joseph

800 bucks a day on coffee on the piston machine.

James Harper

Now, here's why these machines are a liability.

When a barista pulls down that lever, it has to go all the way down and click at the bottom.

And then you can release the handle.

If it doesn't click, it shoots right back up.

And Hyland once had a very near miss.

Hylan Joseph

My ear was next to the handle and it popped up and scratched my ear.

My God.

James Harper

Hyland was centimetres away from being whacked in the face.

He got very, very lucky.

Hylan Joseph

But one time...

So, one day I'm working at the Blue Pair and I'm talking to this lovely Italian girl.

James Harper

When a girl was across the counter...

Hylan Joseph

I'm just smiling at her and I'm wearing a white t-shirt, mind you.

And a white apron.

James Harper

His luck ran out.

Hylan Joseph

And I've pulled down the shot and I'm not paying attention to it.

And my chin is right over the handle and it pops.

Oh no.

And it pops into my chin.

And you heard a cracking noise.

It cut the skin of my chin.

She freaked out.

She freaked out and ran away.

And I looked down and I was like, my hands looked like I was out of a serial killer horror movie.

Yeah.

Oh my God.

Were you seriously hurt?

Damn it, I cracked my jaw.

It was fractured.

So when they x-rayed it, it was really swollen.

I look like I've been punched in the face really hard.

James Harper

But I'm happy to report that in this little horror movie, Hylan did get another chance with the Italian girl.

Did she ever come back?

Yeah, she did.

Hylan Joseph

We went on a date.

Really?

Yeah, it was embarrassing.

But Hylan had never tried to learn the language of love.

My Italian kind of sucks, which means I don't know Italian.

James Harper

His Italian was terrible and her English not good enough either.

Hylan Joseph

Well, she spoke Italian, so it didn't really go very far.

James Harper

And so this little love horror story came to an end.

Winston Churchill

We choose to go to the moon.

James Harper

It's the early 60s.

It's now about 15 years since that first lever machine came to market.

President Kennedy tells Americans.

Winston Churchill

We choose to go to the moon.

James Harper

They're putting a man on the moon by the end of the decade.

Winston Churchill

Not because they are easy, but because they are hard.

James Harper

Italy's streets are flooded with the iconic Fiat 500.

My Italian grandmother gives birth to my mum in a hospital in Rome.

Professor Jonathan Morris

OK, turn around.

James Harper

And the espresso machine, as we know and love today, is born.

Professor Jonathan Morris

This is the machine that changes everything.

This is what I call the coffee machine that changes the world.

This is the Fiamma E61.

James Harper

The Fiamma E61.

It looks like a retro 60s toaster.

Beautiful Italian typography.

A red racing stripe going through the middle of it.

And this espresso machine has two major advances over that lever machine.

A pump and a heat exchanger.

Let's look at the pumps.

Listen, this is old technology.

They've been around for hundreds of years.

But for the first time, they're now affordable.

Giorgio Rancilio

And the way this pump works is very simple.

In the pump is basically two parts.

There's a motor that's been connected to paddles.

James Harper

It's just a motor spinning paddles that push water.

And that creates pressure.

Nine bars to be precise.

So we don't need a lever to create the pressure anymore.

We already have it with the pump.

And so espresso machines ditch that dangerous lever.

And the second big innovation is the heat exchanger.

And this solves the consistency problem I mentioned earlier with the lever machines.

With a lever machine, you can't make that many coffees one after another because you use up the hot water in the boiler.

Then you've got to bring in cold water and you've got to wait for it to heat up.

But this is all solved with a heat exchanger.

Essentially, a little water pipe shaped like a corkscrew nestled inside the water boiler itself.

Giorgio Rancilio

The water in the heating exchanger is heated by the water of the boiler.

James Harper

So the water that actually hits the coffee grounds that, you know, make your espresso, that water isn't coming from the boiler.

It's coming directly from the mains in a little tube.

And this mains water gets hotter and hotter as the metal tube it's in spins around and around surrounded by boiling hot water.

And it lands on your coffee at 93 degrees.

And the result of all this?

Hey, Presto, you never had to stop.

You can now make espresso after espresso after espresso without having to stop to refill the boiler and wait for it to get up to the right temperature.

And, you know, from here on in, it's fair to say that espresso machine technology doesn't really evolve that much.

Giorgio Rancilio

Since the late 60s, basically the technology hasn't changed.

James Harper

You get incremental improvements that make the espresso experience just marginally better.

Instruments to deliver specific amounts of water.

Digital displays.

Changing how much pressure you can apply.

Francilio even made a machine where you can change the water temperature as you brew your espresso.

With this modern style of espresso machine, you know, it still has it.

It still has problems.

Two major problems.

The first is a problem that also afflicts our embattled barista Hyland.

RSI, your repetitive strain injury.

Hylan Joseph

Yeah, I have it in my right hand.

James Harper

How'd you get it?

Hylan Joseph

10 years of putting portafilters on.

James Harper

I have met many baristas with repetitive strain injury from just the motion of putting in the portafilter into the group head.

Hylan Joseph

Think about it, putting the portafilter on, you're putting it on and it requires about 30 pounds of force every time you push it in.

James Harper

30 pounds?

Hylan Joseph

So it's a lot of force.

That's coming from your shoulder and from your wrist.

James Harper

When does it flare up?

Hylan Joseph

It actually became a problem when I took a desk job because I couldn't actually close my hands.

I had to have carpal tunnel surgery on both my hands because of it.

And to be honest with you, I actually have a tremor in my right hand from the shoulder because I was primarily right-handed.

James Harper

So that's the first problem.

Very busy baristas can develop medical problems.

And the second big issue, the operator has to be very well trained to produce a good espresso.

I mean, this has always been the case, but we've solved so many problems that this is now the biggest problem.

Training baristas to make good espresso consistently, not easy.

It's so easy to produce inconsistent espressos between different baristas.

You know, it depends on how hard they tap.

It depends on how much coffee they put in.

It depends on how good they are at assessing the grind size.

And recently, more tools have been coming to market that standardize many of these things.

But still, training good baristas is one of the biggest headaches for a cafe owner.

And espresso engineers know this.

And immediately after the E61 was released in the early 60s, they had been trying to develop machines that replaced the barista entirely.

Hylan Joseph

But the next obvious step is, well, why don't I just go to a super automatic?

James Harper

Technically, they're called super automatics.

And in fact, Starbucks was a major early adopter of these machines in the late 90s.

Hylan Joseph

I mean, Starbucks did it.

They did it with the thermoplane machine.

James Harper

Maybe you haven't even noticed it, but next time you visit a Starbucks, look at the barista and how they make espresso.

They just push a button and out comes the coffee.

But especially coffee cafes would not use the same machines that Starbucks has.

And the perception is it just comes down to quality.

The argument goes, yes, the machines Starbucks uses, they're very impressive internally, but they cannot get close to the flavor experience when you have a highly trained barista working with.

James Harper

Lighter roasted coffee on a traditional espresso machine. But these last 10 years, things have been shifting. If you visit certain specialty coffee shops in New York, London, Taipei, you will find an Eversys.

They are the manufacturers of these super automatics and also the sponsor for this episode. And the reason they're slowly being adopted is because our goal is to be able to control as good as a barista first.

Jonathan Besse

And this, by the way, is Jonathan Bess. I'm R&D director at Eversys.

James Harper

Their goal was to make coffee as good as a good barista. Now, even by their own admission, an Eversys can't make a coffee as good as, you know, a world barista champion. But outside of that group of super baristas working at the best coffee shops in town, from my experience, an Eversys creates a coffee as good as, you know, a well-trained barista in a solid specialty coffee cafe on a busy day.

I've tasted coffees from an Eversys at trade shows over the years. I could drink this coffee every morning. I would.

Also at their factory. It's delicious.

Hylan Joseph

It's great. Great coffee.

James Harper

And even Hyland himself praises the flavor.

Hylan Joseph

I mean, with technology these days, like the Eversys machine makes pretty close to a near-perfect espresso. So why?

James Harper

So what's their secret? What's actually going on inside these machines? And back in the spring, I hopped off the train in the peaceful Swiss village of Sierre.

Cycled down the river that cut in between the Alps to my left and right. Cool. Shall we do a factory tour?

And Jonathan Bess gave me a tour of the Eversys factory. Wow. Okay.

Here we go into the production floor. This is enormous. Oh my God.

This is a huge space. It's 5,000 square meter. And the first thing that strikes me is that I cannot see anything here.

That resembles an espresso machine. It's like the Terminator. It's like I'm walking through the Terminator right now, you know.

Imagine Optimus Prime or, you know, some kind of robot. And you open them up and you take out their insides. Honestly, you get this to anybody and you say, what does this machine do?

No one's going to understand what this thing does. I agree. And all these weird looking boxes with wires and pipes coming out of them, they each perform a very specific task.

Jonathan Besse

All these connections, the plate here that you see with O-rings, an electrical connection here to plug the milk module on top of it.

James Harper

And so this weird looking box over here, that thing froths milk. And this other weird looking box, that thing grinds the coffee. So what it looks like to me is like every single one of those actions by a barista has been replaced instead with a module.

What Eversys has done is they have deconstructed every movement that a barista makes and all the movement inside a traditional espresso machine into modules. And all these modules connect to each other in a very tight box. If you look, if you look, stare into this thing, I mean, there's barely an inch of space really to work with.

So everything has to fit into a very tight container. And now what I want to do is show you the ingenuity of just one of these modules, the brewing module, the process that actually makes espresso. And I'll show you how it has replicated everything that a barista on a traditional espresso machine would do.

So if you're a barista and you get an order for an espresso, first thing you do, fill the portafilter with a precise amount of ground coffee, level out the bed of coffee. Maybe you knock it, you shake it a bit, use a distribution tool. Then you tap it and then lock it into the group head in the espresso machine.

You press a button and keep a careful eye on how much espresso is dripping into your cup. Now, a typical espresso recipe might be 20 grams of ground coffee in, 40 grams of wet espresso out, and for the espresso to brew for about 25 seconds. So when you got your 40 grams of liquid out, you press the button, stop the water, pull the portafilter out from the group head, knock out the wet coffee, wipe the filter basket clean with a rag.

And then you repeat the process all over again. So how does Eversys replicate all of that in a box the size of a football?

Jonathan Besse

Here you see it initializing and moving, the top piston going down.

James Harper

And what I found just mind-blowing... Hold the phone, hold the phone. Okay, okay.

...is that they do replicate it all using just three components. A metal cylinder and two plugs.

Jonathan Besse

The bottom piston will move and it will take the brew chamber under the grinder.

James Harper

So a barista gets an order for an espresso, they press the espresso button. A plug comes in and slots itself underneath into the metal cylinder. The metal cylinder is now plugged up from the bottom.

It moves itself under a chute and in drops the freshly ground coffee.

Jonathan Besse

We can start to grind and fill up the chamber.

James Harper

The ground coffee falls in and the cylinder levels out the coffee with a little shake.

Jonathan Besse

In between is shake to have the ground coffee flat.

James Harper

And now that second plug springs into action. It comes in from above and plugs itself in the cylinder and compresses the coffee.

Jonathan Besse

So we will stem the coffee at 20, 40 or 60 kilos.

James Harper

And then comes a bit that actually blew my mind. Water rises up from that bottom plug, is pushed through the compressed bed of coffee.

Jonathan Besse

The water will go up through the cake.

James Harper

The brewed espresso now goes up through tiny little holes in the top plug into a little tube and lands down in our espresso cups. We now have delicious creamy espresso with a nice layer of crema.

Jonathan Besse

And then how do you remove the coffee? I haven't even thought about that.

James Harper

And then Jonathan blew my mind a second time when he showed me how they clean this metal cylinder. Basically it unplugs from the bottom. With the bottom open and with the top piston you push it out.

It's literally the same way you clean an AeroPress. The bottom plug unplugs itself and the top plug goes all the way through the metal cylinder and then pops out the wet coffee grind.

Jonathan Besse

Down it goes. Yeah, you push it out.

James Harper

So now with machines like the Ephesus, you might think to yourself the barista, we totally replaced their roles. And this is actually a place of huge debate right now in the coffee community. I'm going to argue that we haven't got rid of the barista.

And in fact, what we've done is changed their roles. I was logging into the screen and then I selected... Jonathan took me through all the parameters you can adjust on an Ephesus.

Jonathan Besse

I select the water quantity. I select the coffee quantity. Then the compression force we discuss.

And we have pre-infusion parameter. And it was really quite overwhelming. And we have what we call the second tamping.

James Harper

So what we now need are people who really understand how changing different parameters on this machine change the flavours. In some ways, we're going back in time.

Jonathan Besse

That was not even called barista, it was called machinist.

James Harper

We need people who really understand the intricacies of this machine and are experts at coffee extraction. And now here's something you probably weren't expecting me to say. This machine is not perfect.

What if we do away with the skilled operator entirely? What if he just poured a bag of beans in the top and the machine instantly understood what the beans are and how to make the most sublime espresso for your unique tastes. And if and when we ever figure that out, even that's not perfect.

Because you know what's even more perfect than that? Making it cheap enough to put into my kitchen. And this is what I really enjoyed as I explored this story about espresso machine technology.

The goalposts keep shifting and engineers rise to the challenge and find the most surprising, ingenious solutions. Cannot wait to see where we head next. So thank you for listening to this episode on espresso technology.

And surprisingly, it was actually one of the more challenging episodes to make in this science series. I mean, the first draft was like over an hour long and was stuffed full of so much information. But finding that balance between the nerdy coffee science stuff, the social insights, the beauty of the machines, the hard thing was not finding material.

The hard thing was deciding what to cut. Anyway, I hope you enjoyed it. And while you're listening, maybe you imagined your biggest espresso nerd friend.

And you know what would mean so much to me? Tell them about this episode. Share this episode right now on WhatsApp to your biggest espresso nerd friend.

But seriously, I really rely on peeps like you spreading awareness about this series and filter stories. So thank you for sharing it. Now, this episode was a product of the time and insights of many fantastic people, Professor Jonathan Morris.

And by the way, we created a podcast series, A History of Coffee, which is probably my most popular podcast to date. And it's been heard over 100,000 times. So if you want more of the historical stuff, check it out, link in the show notes.

I want to give a huge thanks to Anna Cento and the team at Cimbali and Mumac. From Rancilio, Giorgio himself, Giorgio Rancilio, Carlos Gonzalez and the team, Silvio Bartoloni and everybody at L'Academia del Caffè for offering me such a wonderful time when I went to visit them in Florence. And who can forget Hylan Joseph telling me all about his war stories.

And also very importantly, the team at Eversys, Jonathan Besse, Alexander Rossier, Aurore Studer and Kamal Bengougam. Without them, this episode couldn't come to fruition. And if you want to learn more about how Eversys makes their machines, I've got a link in the show notes.

Now, there are two more episodes left in the science of coffee. In the next episode, I show you the magical world of creating good latte foam. And I bust a coffee myth.

You know, attached to many espresso machines, there is a steam wand. And we often say, you know, we steam milk or in the case of the next episode, we steam Oatly. But here's the thing, we're not actually steaming Oatly.

We're entraining air into Oatly. So that's the next episode of foam. The final episode is on sonic seasoning and the R&D landscape in coffee.

And one thing you will have noticed is that a lot of the development in espresso machine technology, a lot of it has been focused on user functionality, which is the same approach that the grinder manufacturer Fioranzato take when they do R&D. And if you rewind right to the beginning, the first episode explores what is good water for coffee. And when it comes to espresso machines, having your water filtered like you can with a BWT water filtration system is very important.

Because I show you what happens when you have too many and also not enough minerals in your water and how it can ruin your espresso machine boiling. And then in the second episode, we explore how to get good flavors from your coffee, coffee extraction. And I tell you the development journey behind Marco Beverage Systems SP9 brewer.

And fun fact, just like Eversys, they are made by hand and not by robots. And the episode before this one explores coffee genetics. And I take you with me as I visit coffee farmers who are working with Triboca, a green bean supplier in Kenya to show you how they are trying to overcome the effects of climate change.

Now, The Science of Coffee was produced by me, James Halper. I also write and play the piano music. I want to give a huge thanks to Peter Giuliano and Britta Fulmer for their editorial guidance.

And again, thank you very much for listening. Take care, enjoy your espressos, and I'll speak to you later.