

The Science of Coffee
James Harper
The Science of Coffee is a journey into coffee’s hidden microscopic secrets to help you make even better coffee at home.
Documentary maker and coffee professional James Harper travels the world and speaks with leading coffee scientists to help you appreciate coffee more deeply.
You are going to get taken into the science of water, coffee extraction, plant genetics, espresso technology, latte foam, sonic seasoning, our sense of taste and smell, organic farming, roasting, grinding and freshness, and how to think like a scientist.
Press the Subscribe button so you don’t miss future episodes!
The Science of Coffee is a spin-off series from James Harper’s documentary podcast Filter Stories.
Follow James on Instagram: https://bit.ly/2Mlkk0O
Listen to Filter Stories: https://bit.ly/3ajoT5
Documentary maker and coffee professional James Harper travels the world and speaks with leading coffee scientists to help you appreciate coffee more deeply.
You are going to get taken into the science of water, coffee extraction, plant genetics, espresso technology, latte foam, sonic seasoning, our sense of taste and smell, organic farming, roasting, grinding and freshness, and how to think like a scientist.
Press the Subscribe button so you don’t miss future episodes!
The Science of Coffee is a spin-off series from James Harper’s documentary podcast Filter Stories.
Follow James on Instagram: https://bit.ly/2Mlkk0O
Listen to Filter Stories: https://bit.ly/3ajoT5
Episodes
Mentioned books

Jan 29, 2024 • 38min
Coffee Roasting, Part 1: How heat transforms coffee beans
Discover the fascinating process of coffee roasting and how heat transforms coffee beans. The podcast explores the flavor evolution from acidic to bitter, the chemical and physical transformations during roasting, and the potential impacts of advanced technology on the industry.

Jan 15, 2024 • 39min
Smell and Taste, Part 2: Are you and me tasting the same flavours?
This podcast explores why people taste coffee differently, discussing genetic variations in flavor receptors, the influence of external factors like cup shape and music, and the impact of cultural backgrounds. It also touches on the consistency of coffee brewing, the science of roasting, and the challenges of organic farming.

Jan 8, 2024 • 45min
Smell and Taste, Part 1: How to be a better coffee taster
Discover the fascinating connection between smell and taste, how our brain deceives us into tasting aromas on our tongue. Explore the mystery of sweetness in specialty coffee and the science of sweet receptors. Dive into the role of smell in coffee tasting and the impact of humidity. Get a preview of upcoming topics and the importance of scientific methodology.

Jan 2, 2024 • 2min
Introducing: Season 2 of The Science of Coffee
We’re back with another series of The Science of Coffee!
Across 10 science stories, narrative audio producer and coffee professional James Harper takes you on a journey into coffee's hidden microscopic secrets.
James has spent the last year traveling to Central America, Greece, Norway, Switzerland and interviewing dozens of the world’s leading coffee scientists. This insights will help you appreciate coffee more deeply and make even better coffee at home.
We'll explore organic coffee growing, delve into the science of roasting, uncover optimal storage and grinding techniques, enhance your tasting skills through sensory science, and share James' journey towards thinking more like a scientist.
Press the Subscribe button so you don't miss future episodes! https://bit.ly/3TdDnHO
Follow James on Instagram: https://bit.ly/2Mlkk0O
The Science of Coffee is a spin-off series from James Harper's documentary podcast Filter Stories: https://bit.ly/3ajoT5e
The Science of Coffee is made possible by these leading coffee organisations:
BWT Water and More
Mahlkönig
Marco Beverage Systems
Sustainable Harvest
ROEST

Jan 3, 2023 • 54min
6) Sonic Seasoning
Imagine you’ve got a cup of coffee in front of you. You haven’t tasted it yet. You therefore don’t know what it tastes like, right?
Wrong. Some scientists argue that you actually do know what it will taste like (more or less), and the act of tasting simply confirms what you have already imagined it will taste like. And that’s because a growing body of research is revealing that sight, sound and touch all affect your expectation of a coffee’s flavours.
In this episode, I explore how certain sounds might make your coffee taste sweeter, while other sounds translate to bitterness. And I expose how some cafe owners might be ruining the flavours of the high-end specialty coffee you paid for without even realising it.
In the second half, I show you why so many of our scientific questions about coffee are going unanswered. I take you deep into the future of coffee science by explaining who’s doing research into coffee science, why they’re doing it, how much it costs and how you can get involved.
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Please spread the word about The Science of Coffee!
Follow me on Instagram and tag me in an Instagram story
Write a review on Apple Podcasts
Leave a 5 star rating on Spotify
Explore the technology behind Fiorenzato’s AllGround home coffee grinder
Want to listen to more documentary podcasts about coffee? Check out my Filter Stories podcast
Get more involved in coffee science!
Buy Brita Folmer’s The Craft & Science of Coffee
Read the Specialty Coffee Association's 25 Magazine for cutting edge insights into coffee science, business and sustainability, including Charles Spence’s article on sonic seasoning
Partner with the Coffee Science Foundation
Explore Felipe Reinoso Carvalho’s sonic research, including Diego Campos’ winning World Barista Championship routine
Apply to study at the UC Davis Coffee Centre
Do an online course with ZHAW’s Coffee Excellence Centre
Subscribe to Barista Hustle and complete their online coffee courses
Become a member of the Barista Guild, Coffee Roaster’s Guild, Coffee Technicians Guild and attend their events!
Connect with my very knowledgeable guests
Charles Spence - Academic profile
Fabiana Carvalho - Instagram
Janice Wang - LinkedIn
Felipe Reinoso Carvalho - LinkedIn
Chahan Yeretzian - LinkedIn
Bill Ristenpart - Academic profile
Peter Giuliano - LinkedIn
Jenn Rugolo - LinkedIn
Giulia Bagato - LinkedIn
Denis Girardi - LinkedIn
The Science of Coffee is made possible by these leading coffee organisations
BWT Water and More
Marco Beverage Systems
Trabocca
Eversys
Oatly
Fiorenzato
Subscribe to A History of Coffee podcast

Jan 3, 2023 • 43min
5) Latte Foam
When was the last time you picked up a cappuccino with a mountain of foam perched on top? Maybe these are the cappuccinos you make every morning at home.
I personally really, really dislike them! The foam is cold, raspy, and gets in the way of the actual coffee liquid.
How much better would your mornings be if, instead, your cappuccino had that creamy, silky “microfoam” you find in a specialty coffee cafe?
In this episode, I take you deep into the bubbles of latte foam to show you what makes them, what destroys them, and how you can craft mouth-melting lattes.
Along the way I also settle the big debate: what is the actual difference between regular Oatly and Oatly Barista Edition!?
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Please spread the word about The Science of Coffee!
Follow me on Instagram and tag me in an Instagram story
Write a review on Apple Podcasts
Leave a 5 star rating on Spotify
Try Oatly Barista Edition (this episode’s sponsor) for yourself
Want to listen to more documentary podcasts about coffee? Check out my other show, Filter Stories
Go deeper into latte foam science!
Measure your latte foam’s bubble size!
Marvel at tetrakaidecahedra foam for yourself
Check out Steven Abbott’s brilliant science website
Learn how to create microfoam with Lance Hedrick
Study milk science with Barista Hustle’s online courses
Connect with my very knowledgeable guests
Steven Abbott - website
Rituja Upadhyay - LinkedIn
Nidhi Bansal - LinkedIn
Thom Huppertz - LinkedIn
Sofia Eldhe - LinkedIn
Toby Weedon - LinkedIn
The Science of Coffee is made possible by these leading coffee organisations
BWT Water and More
Marco Beverage Systems
Trabocca
Eversys
Oatly
Fiorenzato
Subscribe to A History of Coffee podcast

Jan 3, 2023 • 43min
4) Espresso Technology
A good espresso is a sublime experience: rich, sweet, and wonderfully caffeinated.
But, who woke up one morning and thought to themselves, ‘I’m going to build a contraption that forces a tiny amount of super hot water with incredible pressure through a bed of very finely ground coffee’?
Well, the fact is, the first “espresso” machine built 150 years ago was awful in almost every way. Worst of all, if you gave that coffee to anybody on the street, nobody would say it’s even an espresso!
But, over the decades, problems begat solutions that begat more problems that culminated in espresso machines like Eversys that produce gorgeous espressos at just the push of a button.
And it’s got me wondering: what is the perfect espresso machine? How far can we go?
But, before clicking play, be warned: this story gets explosive and bloody!
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Please spread the word about The Science of Coffee!
Follow me on Instagram and tag me in an Instagram story
Write a review on Apple Podcasts
Leave a 5 star rating on Spotify
Learn more about how Eversys espresso machines (this episode’s sponsor) produce high quality espressos
Listen to my A History of Coffee podcast series with Prof. Jonathan Morris
Want to listen to more documentary podcasts about coffee? Check out my other podcast, Filter Stories
Pictures of the espresso machines featured in this episode
Angelo Moriondo (1884, “Big water boiler with gnarly bits”)
La Pavoni Ideale (1905, "Fire hydrant")
Gaggia Tipo Classica (1947, “Lever”)
Faema E61 (1961, “Retro 60s toaster”)
Eversys (2022, “push button”)
Want to go deeper into espresso machine technology?
Coffee Technician Guild’s Educational Courses
Barista Hustle’s The Espresso Machine course
Read Prof. Jonathan Morris’ book ‘Coffee: A Global History’
Do your own coffee museum tour in Italy!
MUMAC (Milan)
Rancilio Officina 1926 (Milan)
Accademia del Caffè Espresso (Florence)
Connect with my very knowledgeable guests
Jonathan Morris - Instagram
Hylan Joseph - LinkedIn
Giorgio Rancilio - LinkedIn
Anna Cento - LinkedIn
Carlos Gonzàlez - LinkedIn
Silvia Bartoloni - LinkedIn
Jonathan Besse - LinkedIn
The Science of Coffee is made possible by these leading coffee organisations
BWT Water and More
Marco Beverage Systems
Trabocca
Eversys
Oatly
Fiorenzato
Subscribe to A History of Coffee podcast

Oct 25, 2022 • 1h 3min
3) Plant Genetics
Discover how climate change is wreaking havoc on coffee quality and farmer livelihoods. Explore innovative genetic research aimed at creating resilient coffee plants, including the potential of lesser-known species. Hear inspiring stories from Kenyan farmers overcoming challenges with sustainable practices. Listen in as experts highlight the urgent need for investment in the coffee industry to ensure that the beans you'll savor won’t diminish in quality. It's about more than just better brews; it's a critical call to action for all coffee lovers!

Oct 25, 2022 • 53min
2) Coffee Extraction
The way you brew coffee can turn a delightful cup into a disaster. Discover the science of extraction and how factors like temperature and water quantity shape flavor profiles. Experimenting with different brewing methods, like the AeroPress, reveals surprising taste transformations. Learn why consistency in specialty coffee remains a challenge for cafes and how innovative brewing tech aims to solve it. Dive into the intricate relationship between water temperature and flavor perception to find your perfect brew.

Oct 25, 2022 • 1h 1min
1) Water For Brewing Coffee
Discover how the quality of water can transform your coffee experience! Journey back billions of years to explore how calcium influences flavor, and learn why mineral-rich waters can make your brew shine. Uncover the surprising impact of limescale on espresso machines and how proper water chemistry plays a crucial role in achieving the perfect shot. Plus, find environmentally friendly tips for sourcing quality water at home. This tale intertwines science, geology, and a passion for coffee that will leave you brewing in bliss!