

Filter Stories - Coffee Documentaries
James Harper
Coffee stories with an extra shot of history and science. Filter Stories is a podcast revealing coffee’s hidden microscopic secrets, its powerful past, and how your choice of beans impacts tens of millions of people.
See the behind-the-scenes stories on Instagram @filterstoriespodcast.
If you haven’t already, please subscribe to the show and review us on Apple Podcasts and Spotify!
See the behind-the-scenes stories on Instagram @filterstoriespodcast.
If you haven’t already, please subscribe to the show and review us on Apple Podcasts and Spotify!
Episodes
Mentioned books

Jan 5, 2026 • 50min
We Built This City…On Coffee: Hamburg and the making of Europe's coffee trade
On a long walk through Hamburg, somewhere between the fish markets and giant cranes, you might stumble a giant bronze coffee bean looks like its crash landed from space.
But this giant coffee bean represents a staggering fact: one in every three cups of coffee drunk in Europe has passed through Hamburg.
In the first half of this episode, we explore the many profound ways coffee shaped one of Europe’s most important cities.
But then the story flips because, once coffee changed Hamburg, Hamburg began to change coffee.
Series 3 of A History of Coffee is a collaboration between documentary maker James Harper of the Filter Stories coffee podcast and Jonathan Morris, Professor of History and author of ‘Coffee: A Global History’.
Please spread the word about A History of Coffee!
Follow us on Instagram - James (@filterstoriespodcast) and Jonathan (@coffeehistoryjm) - and tag us in an Instagram story.
Write a review on Apple Podcasts
Leave a 5 star rating on Spotify
This free educational content for the coffee community was made possible by Mahlkönig, manufacturers of world-leading coffee grinders for 100 years for your home and cafe.
Read Jonathan’s book, ‘Coffee: A Global History’ (https://amzn.to/3dihAfU)
Support James’ work directly by buying him a coffee at Ko-fi.com/FilterStories
Pick up a copy of Margrit Schulte Beerbühl’s book, Kaffee Ist Fertig!
Read James’ article on Frederick the Great’s attempt to ban coffee in Standart
Go on your own Hamburg coffee tour!
Giant bean
Speicherstadt Museum
Burg Coffee Museum in the Speicherstadt
Becking, 100 year old coffee roasters
1950s Rebuilt Coffee Exchange - and an Instagram post coming on @filterstoriespodcast
Go deeper into the story of Mahlkönig’s grinders
Early EKs - post coming on @filterstoriespodcast
DK (aka Donkey Kong Dreiphasen Kaffeemühle)
Grind-by-Sync espresso grinders
EK Omnia
Guatemala
Matt Perger WBC routine demonstrating the EK
Filter Stories episode on grinding curves
How does Perfect Moose detect what kind of milk is in the pitcher? Click here to find out.
Join me at World of Coffee Dubai, 18-20 January. Grab your tickets here.
What does the Marco MilkPal look like to you? WALL-E? Something Steve Jobs would be proud of? Check it out here.

Dec 29, 2025 • 3min
Introducing: Series Three of A History of Coffee
We’re back with more stories about the tiny psychoactive seed that changed the world and continues to shape our lives today.
Is it possible to follow the story not just to Ethiopia, not just to a single town, but all the way back to one tree?
We’ll uncover the uncomfortable history of Guatemala — a story about who inherited the rich volcanic soil, and who was forced to work it.
We explore what happens when our worst nightmare comes true: coffee disappears from the shelves. What did people brew instead? Was any of it actually drinkable?
And we tell the story of how coffee can shape the massive port city of Hamburg, and how Hamburg then went on to shape the global coffee world.
If we want to make coffee a more equitable industry that’s also kinder to the environment, a place to start is understanding the stories and systems that put the coffee into your cup this morning.
Press the ‘Subscribe’ button so you don’t miss future episodes.
A History of Coffee is a collaboration between documentary maker James Harper of the Filter Stories coffee podcast and Jonathan Morris, Professor of History and author of ‘Coffee: A Global History’.
Follow us on Instagram! Jonathan Morris @coffeehistoryjm and James Harper @filterstoriespodcast.
This free educational content was made possible with the support of Mahlkönig, manufacturers of world-class grinders for 100 years.
Subscribe to The Science of Coffee podcast
How does Perfect Moose detect what kind of milk is in the pitcher? Click here to find out.
Join me at World of Coffee Dubai, 18-20 January. Grab your tickets here.
What does the Marco MilkPal look like to you? WALL-E? Something Steve Jobs would be proud of? Check it out here.

Dec 8, 2025 • 30min
Coffee Quality, Part 3: When the “quality” myth hits the farm
For twenty years, the 2004 cupping form profoundly shaped the specialty coffee world.
But on the hillsides of coffee farms, some of the form’s byproducts have been disadvantaging producers.
In this episode, we follow two producers whose lives collided with the myth of universal quality. These stories reveal how a single idea of “quality” can close doors for the people with the least power in the supply chain.
The new coffee evaluation form, the CVA, is still young, and with any luck it will keep evolving. I hope for a form that can empower even the smallest producers.
Please support my work directly at Ko-fi.com/FilterStories
Other ways you can help:
Leave a 5 star rating on Spotify
Follow me on Instagram and tag me in an Instagram story
Write a review on Apple Podcasts
Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter
Go deeper into the story of quality:
The original Filter Stories episode about Murray Cooper in Ecuador, Firefly
Specialty Coffee Association's new Coffee Value Assessment
2004 cupping form from the Specialty Coffee Association of America
SCAA Coffee Cuppers Handbook (4th edition, 2011)
Kenneth Liberman's book, "Tasting Coffee: An Inquiry into Objectivity"
SCA's video series on the CVA presented by Peter Giuliano
How does Perfect Moose detect what kind of milk is in the pitcher? Click here to find out.
Join me at World of Coffee Dubai, 18-20 January. Grab your tickets here.
What does the Marco MilkPal look like to you? WALL-E? Something Steve Jobs would be proud of? Check it out here.

Dec 8, 2025 • 26min
Coffee Quality, Part 2: How “quality” became a myth
If you ask two specialty professionals what makes a high-quality coffee, you’ll likely get a surprisingly consistent answer: clean, sweet, juicy, bright. To an outsider, they would be forgiven for thinking coffee quality is universally defined.
But the truth is more sober.
In this episode, we examine how a simple cupping form helped create a universal idea of quality. We then look at the evidence that, in fact, it’s just the personal preferences of a small group of people masquerading as universal quality.
Please support my work directly at Ko-fi.com/FilterStories
Other ways you can help:
Leave a 5 star rating on Spotify
Follow me on Instagram and tag me in an Instagram story
Write a review on Apple Podcasts
Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter
Go deeper into the story of quality:
2004 cupping form from the Specialty Coffee Association of America
SCAA Coffee Cuppers Handbook (4th edition, 2011)
Cup of Excellence cupping form
Kenneth Liberman's book, "Tasting Coffee: An Inquiry into Objectivity"
SCA's video series on the CVA presented by Peter Giuliano
How does Perfect Moose detect what kind of milk is in the pitcher? Click here to find out.
Join me at World of Coffee Dubai, 18-20 January. Grab your tickets here.
What does the Marco MilkPal look like to you? WALL-E? Something Steve Jobs would be proud of? Check it out here.

Dec 8, 2025 • 24min
Coffee Quality, Part 1: The birth of specialty coffee flavours
For the longest time, coffees were dull and bitter. But then a small group of pioneers changed the world.
In this episode, we travel back to the 1960s and ’70s to meet the trailblazers who realised coffees could taste distinctive: sweeter, brighter, cleaner.
We discover how their personal preferences became a movement, then a form, and eventually a global definition of “quality”.
Please support my work directly at Ko-fi.com/FilterStories
Other ways you can help:
Leave a 5 star rating on Spotify
Follow me on Instagram and tag me in an Instagram story
Write a review on Apple Podcasts
Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter
Go deeper into the story of quality:
Specialty Coffee Association's new Coffee Value Assessment
2004 cupping form from the Specialty Coffee Association of America
SCAA Coffee Cuppers Handbook (4th edition, 2011)
Michael Sheridan of CQI discussing the inter-organisational politics behind the Houston Expo announcement on Lee Safar's Map It Forward podcast
How does Perfect Moose detect what kind of milk is in the pitcher? Click here to find out.
Join me at World of Coffee Dubai, 18-20 January. Grab your tickets here.
What does the Marco MilkPal look like to you? WALL-E? Something Steve Jobs would be proud of? Check it out here.

Jul 28, 2025 • 26min
How specialty coffee woke up to water’s role in flavour
For the longest time, the coffee community only cared about water’s impact ruining espresso machine boilers and kettles. But what about water’s impact on coffee flavour?
In this episode, I tell the story of how the specialty coffee community came to understand water chemistry: the pioneering work of the computational chemist Christopher Hendon and British roaster Maxwell Colonna-Dashwood, the genesis of the SCA’s Water Quality Handbook, and where we are today understanding the impact of minerals on our water.
I strongly recommend listening to the two episodes before this one first Getting great water for coffee, step-by-step & The two ingredients in water that ruin your coffee, and the ancient story behind them
Please spread the word about The Science of Coffee!
Leave a 5 star rating on Spotify
Follow me on Instagram and tag me in an Instagram story
Write a review on Apple Podcasts
Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter
Want to go deeper into water chemistry?
Read the SCA’s Water Quality Handbook
BWT White Paper on the effects of magnesium (German)
Christopher Hendon’s Instagram where he’ll announce his new version of his book, Water for Coffee
Do an online Certificate of Advanced Studies at the Coffee Excellence Centre
Season 3 of The Science of Coffee is made possible by these leading coffee organisations:
The Coffee Quest | BWT | TODDY | Algrano | Probat
Note: this is a reworked version of my 2022 episode Water for Brewing Coffee, including portions of my 2024 episode How to think like a scientist, part 2.
How does Perfect Moose detect what kind of milk is in the pitcher? Click here to find out.
Join me at World of Coffee Dubai, 18-20 January. Grab your tickets here.
What does the Marco MilkPal look like to you? WALL-E? Something Steve Jobs would be proud of? Check it out here.

Jul 28, 2025 • 39min
The two ingredients in water that ruin your coffee, and the ancient story behind them
550 million years ago, earth was perfect. We had perfect water for coffee AND we were living in a vegetarian paradise!
But then Earth changed—violently. The planet shifted from a peaceful, plant-eating paradise to a darker, more brutal world. And in this new world, the chemistry of water was forever altered.
This is the wild story of how earth-shaking forces and the spirits of long-dead critters ruin your coffees today.
This story will help you remember the two invisible ingredients in your water that have a huge impact on coffee flavour and your brewing equipment: calcium and hydrogen carbonate.
Read Marcia Bjonerud’s amazing book, Reading the Rocks
Please spread the word about The Science of Coffee!
Leave a 5 star rating on Spotify
Follow me on Instagram and tag me in an Instagram story
Write a review on Apple Podcasts
Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter
Season 3 of The Science of Coffee is made possible by these leading coffee organisations:
The Coffee Quest | BWT | TODDY | Algrano | Probat
Note: this is a reworked version of my 2022 episode Water for Brewing Coffee.
How does Perfect Moose detect what kind of milk is in the pitcher? Click here to find out.
Join me at World of Coffee Dubai, 18-20 January. Grab your tickets here.
What does the Marco MilkPal look like to you? WALL-E? Something Steve Jobs would be proud of? Check it out here.

Jul 14, 2025 • 43min
Getting great water for coffee, step-by-step. Part 2: How to measure and treat your water
Water massively impacts your coffee’s flavours. But most of us struggle to fix our water because water science is confusing…
…until now! In this special collaboration with Lucia Solis (Making Coffee podcast), I guide her through the two most important concepts you need to understand to get great-tasting water for coffee: hardness and alkalinity.
We go step-by-step through:
• Why these concepts matter for coffee flavour and equipment
• How to test your water at home
• How to fix it, depending on what you’re working with
These aren’t one of my usual narrative episodes—they’re a straightforward, practical guide to help you take control of your water.
By the end of these episodes, you’ll be able to say: “I know what good water for coffee is and how to get it”.
I hope it helps you as much as it helped Lucia.
Check my website for all the visuals mentioned in this episode, including:
SCA graph for excellent water (the “map”)
Map of different water hardness across Paris
My Berlin water report
The nightmarish table of conversions…
Results from my water tests in my Berlin studio
Bottled water brands rated for their hardness and alkalinity
Please spread the word about The Science of Coffee!
Leave a 5 star rating on Spotify
Follow me on Instagram and tag me in an Instagram story
Write a review on Apple Podcasts
Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter
Resources mentioned in the episode:
SCA’s Water Quality Handbook
Hardness and alkalinity dripper testing kit (also good for keeping your fishies happy)
BWT Penguin Filter Jug (what I used to use with the magnesium cartridges)
BWT BestAqua ROC (what now I use)
BWT BestBarista (for cafes)
Create your own water by adding minerals to very soft or distilled water: JoJo Hersh’s simple calculator using epsom salts and bicarbonate of soda, and Barista Hustle’s more elaborate one.
Want to go deeper into water chemistry?
BWT White Paper on the effects of magnesium (German)
Christopher Hendon’s book Water for Coffee
Do an online Certificate of Advanced Studies at the Coffee Excellence Centre
Read The Craft and Science of Coffee
Barista Hustle's Water course
Some water content on YouTube by James Hoffman and Lance Hedrick
Season 3 of The Science of Coffee is made possible by these leading coffee organisations:
The Coffee Quest | BWT | TODDY | Algrano | Probat
How does Perfect Moose detect what kind of milk is in the pitcher? Click here to find out.
Join me at World of Coffee Dubai, 18-20 January. Grab your tickets here.
What does the Marco MilkPal look like to you? WALL-E? Something Steve Jobs would be proud of? Check it out here.

Jul 14, 2025 • 26min
Getting great water for coffee, step-by-step. Part 1: Alkalinity, hardness and why it matters
Water massively impacts your coffee’s flavours. But most of us struggle to fix our water because water science is confusing…
…until now! In this special collaboration with Lucia Solis (Making Coffee podcast), I guide her through the two most important concepts you need to understand to get great-tasting water for coffee: hardness and alkalinity.
We go step-by-step through:
• Why these concepts matter for coffee flavour and equipment
• How to test your water at home
• How to fix it, depending on what you’re working with
These aren’t one of my usual narrative episodes—they’re a straightforward, practical guide to help you take control of your water.
By the end of these episodes, you’ll be able to say: “I know what good water for coffee is and how to get it”.
I hope it helps you as much as it helped Lucia.
Check my website for all the visuals mentioned in this episode, including:
SCA graph for excellent water (the “map”)
Map of different water hardness across Paris
My Berlin water report
The nightmarish table of conversions…
Results from my water tests in my Berlin studio
Bottled water brands rated for their hardness and alkalinity
Please spread the word about The Science of Coffee!
Leave a 5 star rating on Spotify
Follow me on Instagram and tag me in an Instagram story
Write a review on Apple Podcasts
Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter
Resources mentioned in the episode:
SCA’s Water Quality Handbook
Hardness and alkalinity dripper testing kit (also good for keeping your fishies happy)
BWT Penguin Filter Jug (what I used to use with the magnesium cartridges)
BWT BestAqua ROC (what now I use)
BWT BestBarista (for cafes)
Create your own water by adding minerals to very soft or distilled water: JoJo Hersh’s simple calculator using epsom salts and bicarbonate of soda, and Barista Hustle’s more elaborate one.
Want to go deeper into water chemistry?
BWT White Paper on the effects of magnesium (German)
Christopher Hendon’s book Water for Coffee
Do an online Certificate of Advanced Studies at the Coffee Excellence Centre
Read The Craft and Science of Coffee
Barista Hustle's Water course
Some water content on YouTube by James Hoffman and Lance Hedrick
Season 3 of The Science of Coffee is made possible by these leading coffee organisations:
The Coffee Quest | BWT | TODDY | Algrano | Probat
How does Perfect Moose detect what kind of milk is in the pitcher? Click here to find out.
Join me at World of Coffee Dubai, 18-20 January. Grab your tickets here.
What does the Marco MilkPal look like to you? WALL-E? Something Steve Jobs would be proud of? Check it out here.

Jun 23, 2025 • 54min
Farm to port: why specialty costs more
Every time we open a bag of beautiful specialty coffee — like Erick Bravo’s from Finca El Chaferote in Huila, Colombia — we’re drinking something that’s been on a long journey.
And I mean long! Over 1500 kilometers north up and down the Andes mountain range, a distance more than twice the height of France.
Along the way, it passes through dozens of hands, machines, and decisions. We follow it through muddy mountain sides, dusty dry mills, and hurricane-battered coastal warehouses — places where all kinds of things can go wrong. A leaky roof. An overly aggressive polishing machine. Or even theft.
But here’s the mystery: getting Erick’s coffee to port costs 50% more than sending a commodity coffee through the same route.
Why?
That question led me deep into Colombia’s coffee supply chains — and what I found changed how I think about the real cost of treating coffee with care.
Please spread the word about The Science of Coffee!
Leave a 5 star rating on Spotify
Follow me on Instagram and tag me in an Instagram story
Write a review on Apple Podcasts
Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter
Find your next favourite Colombian coffee from The Coffee Quest
Taste coffees from Erick Bravo’s award winning farm, Finca El Chaferote, and follow him on Instagram.
Season 3 of The Science of Coffee is made possible by these leading coffee organizations:
The Coffee Quest | BWT | TODDY | Algrano | Probat
How does Perfect Moose detect what kind of milk is in the pitcher? Click here to find out.
Join me at World of Coffee Dubai, 18-20 January. Grab your tickets here.
What does the Marco MilkPal look like to you? WALL-E? Something Steve Jobs would be proud of? Check it out here.


