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Feb 2025
45m 15s

Hot vs Cold: The science behind temperat...

JAMES HARPER
About this episode

For years, I used cold brew as a last resort—the only brew method to tame dark, oily beans that were too bitter for hot water. 

 

Then one day, I took a chance on a Guatemalan Gesha and brewed it cold. The result? A massive explosion of florals I’d never tasted before. That single cup sent opened my eyes into how extraordinary cold brew can be.

 

In this episode, I speak with world-leading coffee scientists who explain why brewing with cold water tastes so different from chilled hot coffee. 

 

You’ll learn how certain flavors leap into your cup (and how others mysteriously vanish) when you lower the brew temperature.

 

You’ll also discover there are hidden “cold brew gems” in beans you thought you knew. So before you grab the kettle, consider this: sometimes all you need is cold water.

 

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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 Explore TODDY’s cold brewing kits

 

 

Go deeper into the science of cold brew

 

Do a Certificate of Advanced Studies with the Coffee Excellence Centre

Listen to my episode on Coffee Extraction for insights into how polarity affects flavor extraction

Read the UC Davis cold brew vs chilled hot brew study

Listen to my episode on 'How to think like a scientist'

Learn how to do a cold brew cupping with Toddy

Follow Filter Stories on Instagram for my acidity infographic

Go deeper into Paul Breslin's work at the Monell Chemical Senses Centre

Discover all of UC Davis' cold brew research through the Coffee Science Foundation

 

 

Season 3 is made possible by these leading coffee organizations:

 

The Coffee Quest | BWT | TODDY | Algrano | Probat

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