Coffee Roasting, Part 1: How heat transforms coffee beans

Deep inside your coffee grinder, tiny changes can have massive consequences.  This episode takes you deep inside Mahlkönig’s grinders to show you how coffee is ground and the importance of particle sizes on flavour.  If you’re a home coffee lover, you could easily spend thousands of dollars on your coffee grinder. But after diving deep into the R&D of grinder manufacturing, I learned that after a certain point spending more probably won’t produce a better tasting cup of coffee for you!  --------- Please spread the word about The Science of Coffee!  Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter.  Write a review on Apple Podcasts Follow me on Instagram and tag me in an Instagram story Leave a 5 star rating on Spotify Explore Mahlkönig’s range of world leading grinders, trusted by baristas globally. Go deeper into the world of grinding  Take Barista Hustle’s Advanced Espresso course Learn from Lance Hedrick where the sweet spot is for buying a coffee grinder Get super nerdy with Jonathan Gagné’s writings on grinding Read up on Samo Smrke’s work on coffee fines Connect with my very knowledgeable guests  Arnaldo Rodrigues - LinkedIn Luca Lange - LinkedIn Chris Meier - LinkedIn Dario Burger - Instagram The Science of Coffee is made possible by these leading coffee organisations:  BWT Water and More Marco Beverage Systems ROEST Sustainable Harvest Mahlkönig The Science of Coffee is a spin-off series from James Harper's documentary podcast Filter Stories Subscribe to A History of Coffee podcast

For your coffee to taste its best, it’s crucial you buy fresh roasts and grind fresh.… .….Or maybe not.  When I began creating this episode, I was convinced that ‘fresh is best’. But, after delving into the science of coffee freshness, I don’t believe that anymore.  This episode goes deep into how diffusion and oxidation changes a coffee’s flavours. You’ll learn what it takes to store your coffee grounds unbelievably well. So well, that if you do it right, you will struggle to taste the difference between two month old coffee compared to those same beans freshly ground! But here’s the weirdest thing: Maybe, just maybe, you will prefer old coffee more than the fresh stuff. ---------- Please spread the word about The Science of Coffee! Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter.  Leave a 5 star rating on Spotify Follow me on Instagram and tag me in an Instagram story Write a review on Apple Podcasts Explore Mahlkönig’s range of world leading grinders, trusted by baristas globally. Dive deeper into the science of coffee freshness Do a Certificate of Advanced Studies with the Coffee Excellence Centre Pick up a copy of the SCA’s Coffee Freshness Handbook Connect with my very knowledgeable guests Samo Smrke - Instagram 19 Grams Coffee Roasters in Berlin - Instagram Arnaldo Rodrigues - LinkedIn The Science of Coffee is made possible by these leading coffee organisations: BWT Water and More Marco Beverage Systems ROEST Sustainable Harvest Mahlkönig The Science of Coffee is a spin-off series from James Harper's documentary podcast Filter Stories Subscribe to A History of Coffee podcast

In the last episode, I discovered that rinsing my Chemex filter papers was a waste of time! As a result I’ve managed to claw back over seven days of my life left on earth.  But why stop there?  The coffee industry is full of elaborate ways of brewing and savouring coffee: fancy drippers, cold metal balls, “slurp-able” cupping spoons. These are very fun, but how many of them actually affect the flavour of our coffee? I fear elaborate coffee gear is wasting our time and money. They're distracting us from the existential crises in coffee that actually require all our attention now. For example, the issue of farmers who grow delicious coffees quitting the business because it’s just getting too hard.  But to figure out whether a popular new coffee tool was actually waste of time or not, I needed to think like a scientist.  This episode is the journey I went on to rewire my brain: I had to learn what good evidence looks like, what to do if I can’t find good evidence, and why it’s important to focus mostly on experimental results while resisting the allure of a compelling theory.  Please spread the word about The Science of Coffee! Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter.  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 this episode’s sponsor BWT’s water filtration products. I use their Penguin magnesium filter cartridges and cafes can use their BestAqua ROC Dive deeper into the science of slurping, water and Signal Detection Theory Do a Certificate of Advanced Studies with the Coffee Excellence Centre Read Georgiana’s paper on soup slurping Learn more about Signal Detection Theory Explore BWT White Paper on the effects of magnesium (German) Browse Christopher Hendon’s book Water for Coffee  Take Barista Hustle's Water course  Watch James Hoffman's water video Connect with my very knowledgeable guests Morten Munchow - Coffee Mind website Jeremy Nelson - LinkedIn Samo Smrke - Instagram Georgiana Juravle - Google Scholar Young Baek - Instagram Frank Neuhausen - LinkedIn Sergio Barbarisi - LinkedIn Alessandro Genovese - LinkedIn The Science of Coffee is made possible by these leading coffee organisations: BWT Water and More Marco Beverage Systems ROEST Sustainable Harvest Mahlkönig The Science of Coffee is a spin-off series from James Harper's documentary podcast Filter Stories Subscribe to A History of Coffee podcast

Should you rinse your filter paper before making a filter coffee? Almost everybody in coffee internet says you should.  But what if most of coffee internet was wrong? In this episode, I show you how I try to answer this question like a professional sensory scientist would.  It’s hard. It’s frustrating. But ultimately, it’s worth it because I end up saving seven days of my life left on earth! Please spread the word about The Science of Coffee! Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter Leave a 5 star rating on Spotify Follow me on Instagram and tag me in an Instagram story Write a review on Apple Podcasts Bring out vibrancy in your coffee with BWT’s magnesium water filters for the home and cafe Dive deeper into sensory science methodologies Take Becky Bleibaum’s free introductory sensory science course!  Set up a triangulation yourself with DragonflySci’s worksheets Understand Rose Marie Pangborn’s three step process better with Morten Münchow (“Pangborn’s Razor”) Do a Certificate of Advanced Studies with the Coffee Excellence Centre Connect with my very knowledgeable guests Morten Munchow - Coffee Mind website Becky Bleibaum - LinkedIn Samo Smrke - Instagram Sophie Vo - LinkedIn The Science of Coffee is made possible by these leading coffee organisations: BWT Water and More Marco Beverage Systems ROEST Sustainable Harvest Mahlkönig The Science of Coffee is a spin-off series from James Harper's documentary podcast Filter Stories Subscribe to A History of Coffee podcast

Farming coffee organically is amazing because soils are more alive, birds and insects are more plentiful, farmers avoid getting sick with agrochemicals. But, if it’s so great, why is less than 10% of the world’s coffee grown organically? The fact is, going organic is hard. Much harder than growing coffee conventionally. In this episode I show you the story of one of Central America’s most successful organic coffee cooperatives, RAOS, and the four big hurdles that stood in the way of their early founders who all dreamed of converting their farms to organic. This story changed my understanding of farming and is now the reason I choose organic specialty coffee whenever I can. Please spread the word about The Science of Coffee! Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter Follow me on Instagram and tag me in an Instagram story Write a review on Apple Podcasts Leave a 5 star rating on Spotify Dive deeper into organic coffee Learn more about Sustainable Harvest’s Most Valuable Producer programme, their cupping app Tastify, and explore their range of certified organic and Fairtrade coffees Explore RAOS (Cooperativa Regional Mixta de Agricultores Organicos de la Sierra)'s story for yourself Are you a coffee farmer? Get in touch with Lalo Perez Varaona Connect with my very knowledgeable guests Lalo Perez Varaona - LinkedIn Jorge Cuevas - LinkedIn Andrea Futterer - GEPA website Osman Contreras - LinkedIn Roberto Rene Gonzales - Farm website The Science of Coffee is made possible by these leading coffee organisations BWT Water and More Marco Beverage Systems ROEST Sustainable Harvest Mahlkönig The Science of Coffee is a spin-off series from James Harper's documentary podcast Filter Stories Subscribe to A History of Coffee podcast

The world’s farming soils are deteriorating quickly. Conventional coffee farming where plants are grown using agrochemicals allowed farmers to reap huge harvests these last 70 years. But these agrochemicals have been at the expense of soil health. I travel to Honduras to explore a potential solution: organic coffee farming. Come with me as I show you the organic farming tricks of Don Rufino, one of the region’s leading organic farmers. He nurtures the soil around his coffee trees using mountain microorganisms, a huge diversity of shade trees, attentive tree pruning, and very funky batches of homemade bug spray. The results speak for themselves: when I pick up a handful of his soil, it is moist, dense and writhing with life. Could these cultivation techniques be the answer to the coffee world’s declining soil health? Please spread the word about The Science of Coffee! Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter! Follow me on Instagram and tag me in an Instagram story Write a review on Apple Podcasts Leave a 5 star rating on Spotify Dive deeper into organic coffee Explore Sustainable Harvest’s range of certified organic and Fairtrade coffees Are you a coffee farmer? Get in touch with Lalo Perez Varaona Check out Don Rufino’s organic cooperative, RAOS Connect with my very knowledgeable guests Lalo Perez Varaona - LinkedIn Tommie Hooft van Huysduynen - LinkedIn Alison Streaker - LinkedIn The Science of Coffee is made possible by these leading coffee organisations BWT Water and More Marco Beverage Systems ROEST Sustainable Harvest Mahlkönig The Science of Coffee is a spin-off series from James Harper's documentary podcast Filter Stories Subscribe to A History of Coffee podcast

Roasting coffee can be maddening. Just 4° Celsius is enough to make the same green beans taste distinctly different! And there are so many things roasters can play around with: temperature, time, fan speed, drum speed, types of probes…the list goes on and on. So, if you want to start roasting yourself, where do you start!? In the first half of this episode, I interview one of the world's leading roasting teachers who takes me through his published scientific research to give a clear answer. It’s as simple as 80%, 15% and 5%. And then, in the second half, I show you why roasting coffee consistently batch-after-batch is so difficult. But these problems are finally being solved with smart technologies. I visited the ROEST engineering team in Oslo and cracked open their innovative prototype P3000 roaster to show you the technology that allows anybody to roast coffee consistently and fully automatically. I am so impressed with these innovations, I believe they’re going to change the coffee industry. 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 Dive deeper into the science of roasting Explore ROEST’s innovative products for the coffee industry. Learn more from Morten Münchow and his coffee roasting courses Read Morten’s paper in collaboration with the University of Copenhagen on Roasting Conditions and Coffee Flavour Connect with my very knowledgeable guests Sverre Simonsen - LinkedIn Callum Gilmour - LinkedIn Veronica Balduc - LinkedIn Morten Münchow - Coffee Mind website Scott Rao - Instagram The Science of Coffee is made possible by these leading coffee organisations BWT Water and More Marco Beverage Systems ROEST Sustainable Harvest Mahlkönig The Science of Coffee is a spin-off series from James Harper's documentary podcast Filter Stories Subscribe to A History of Coffee podcast

What flavours do you want from your coffee? Every coffee bean begins its life green. And if you brewed it up without first roasting it, you’d get a yellow-green cup of grass-flavoured water. But, as soon you apply heat to a bean, the flavour can morph to from something quite vegetative to a very acidic unripe fruit, then a very sweet fruit, and eventually dark roasted flavours. This is the magic of coffee roasting! In this episode of The Science of Coffee, I show you a full roast in action on the ROEST P3000, taste how coffee flavours evolve from acidic to bitter, and speak to leading coffee roasting scientists to reveal the mind-bending chemical and physical transformations taking place. See for yourself Roest's innovative P3000 fully automatic roaster. 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 Connect with my very knowledgeable guests Mark Al-Shemmeri - LinkedIn Callum Gilmour - LinkedIn Veronica Balduc - LinkedIn Anja Rahn - LinkedInIldi Revi - LinkedIn Samo Smrke - Instagram Morten Münchow - Coffee Mind website The Science of Coffee is made possible by these leading coffee organisations BWT Water and More Marco Beverage Systems ROEST Sustainable Harvest Mahlkönig The Science of Coffee is a spin-off series from James Harper's documentary podcast Filter Stories Subscribe to A History of Coffee podcast

Ever wonder why you and your friends can taste the same coffee, but you can’t agree on the flavour notes? Join me as I explore this metaphysical mystery! I speak with leading scientists and ask: are the flavour receptors in your nose and mouth the same as mine? How does music and the shape of a cup affect what we taste? What about our different cultural backgrounds and language? Best of all, I put all these questions to the test in the Athen’s World of Coffee trade show. Many poor unsuspecting Filter Stories spit, splutter and gasp in the name of science! --------- See Marco Beverage Systems' SP9 for yourself, and discover their range of consistent and energy-efficient coffee brewers for your cafe. 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 Connect with my very knowledgeable guests Helene Hopfer - LinkedIn Joel Mainland - LinkedIn Fabiana Carvalho - Instagram Janice Wang - LinkedIn Felipe Reinoso - LinkedIn Freda Yuan - Instagram Mandy Naglich - Instagram The Science of Coffee is made possible by these leading coffee organisations: BWT Water and More Marco Beverage Systems ROEST Sustainable Harvest Mahlkönig The Science of Coffee is a spin-off series from James Harper's documentary podcast Filter Stories Subscribe to A History of Coffee podcast

So you’ve just taken a sip of a very rare coffee, and flavours of passion fruit explode in your mouth. But here’s the thing: that flavour of passion fruit is not coming from your mouth. It’s not even coming from your nostrils. It’s being picked up behind your eyes! In this first episode of The Science of Coffee's second series, I unravel how our sense of smell and taste works to help you be a better coffee taster. I shrink us down microscopically and we dive into your tongue to show you why good black coffee tastes sweet, even though there’s no sugar in it. We then travel up into our noses and get stuck in a lot of mucus. This slime might be disgusting, but we need it to be able to smell well. And finally, with the help of tasting expert and author Mandy Naglich, I show you three effective ways you can train yourself to be a much better coffee taster without having to go on any expensive courses. The trick is to train our internal flavour prediction models! This episode will help you deepen your appreciation of coffee and its delicious complexity. --------- See Marco Beverage Systems' SP9 for yourself, and discover their range of consistent and energy-efficient coffee brewers for your cafe. 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 Become a better coffee taster! Pick up a copy of Mandy Naglich’s book “How To Taste” Sign up for the Specialty Coffee Association’s Sensory Skills courses Do an online sensory course with CoffeeMind Connect with my very knowledgeable guests Mandy Naglich - Instagram Linda Bartoshuk - Website Joel Mainland - LinkedIn Fabiana Carvalho - Instagram Janice Wang - LinkedIn Peter Giuliano - LinkedIn Bram De Hoog - Instagram The Science of Coffee is made possible by these leading coffee organisations: BWT Water and More Marco Beverage Systems ROEST Sustainable Harvest Mahlkönig The Science of Coffee is a spin-off series from James Harper's documentary podcast Filter Stories Subscribe to A History of Coffee podcast