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Mar 2025
52m 24s

The Speed of Heat: How to roast more cof...

JAMES HARPER
About this episode

To roast coffee faster, you need to turn up the heat….right?

 

No! 

 

In this episode, we explore the three powerful methods of heat transfer that revolutionised roasting. We’ll journey from humble beginnings—when roasting three kilos took half an hour—to machines that now roast hundreds of kilos of coffee in the time it takes you to boil a kettle. 

 

But beans roasted at lightning speed look strange, and taste… well, you’ll find out. Join us as we test-drive an industrial tangential roaster where first crack remind me of fireworks crackers. 

 

We also see the whale-sized roaster so massive it’s worth you a Guinness World Record. 

 

We have the technology today to roast coffee faster than ever, so why aren’t we all roasting at recording-breaking speeds?

 

---------------

 

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

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Check out the Probat roasters mentioned in this episode:

 

Emmerich Spherical Roaster - "Pink Hydrant"

Large ball roaster - “Sputnik in a pizza oven”

G45 early drum roaster - “Old school steam train” 

Early tangential roaster

Sample tangential roaster - "Shoebox"

Neptune 4000, the largest drum roaster in the world! - "The whale"

 

And there are lots of other specialty roasters from Probat I didn't have time to showcase, including their new hydrogen powered roasters. See them all for yourself!.

 

Theodor von Gimborn's wikipedia page

 

 

Go deeper into the science of roasting

 

Read Mark Al-Shemmeri’s coffee roasting blog

Do a Certificate of Advanced Studies with the Coffee Excellence Centre

Explore Barista Hustle's online roasting learning

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

Follow Filter Stories on Instagram for my infographics

Learn more about first crack on my episode Coffee Roasting, Part 1: How heat transforms coffee beans

 

 

Season 3 is made possible by these leading coffee organizations:

 

The Coffee Quest | BWT | TODDY | Algrano | Probat

 

 

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