Ultrasonic Espresso - A New Way to Brew Coffee | FRANCISCO TRUJILLO!

Can you make espresso with room-temperature water and sound waves?

Dr Francisco Trujillo and his team at UNSW have developed an entirely new brewing process that uses ultrasound to produce espresso-strength coffee in under three minutes, while using around one-quarter of the energy of a traditional espresso machine.

In this episode, Francisco takes us inside the science of ultrasonic coffee. We unpack acoustic cavitation, the microscopic bubbles that pit and fracture coffee grounds, why tamping matters far less in this system, and how the team built the technology into something that still looks surprisingly close to a normal espresso machine.

We also get into the taste test. One hundred regular coffee drinkers compared the ultrasonic brew with traditional espresso, with no significant difference found across the key sensory measures. Francisco explains where the drinks do differ, including crema, bitterness and aftertaste, and why the biggest opportunity may not be your local café at all, but large-scale ready-to-drink coffee production.

If you’re new here (welcome), our show dives into some of the best coffee conversations on the internet, but we will always remind ourselves at the end of the day: It’s Just Coffee!

CHAPTERS!

00:00 A New Way to Brew Coffee

01:17 How Ultrasonic Espresso Works

02:18 Where the Idea Came From

03:29 From Three-Minute Cold Brew to Espresso Strength

04:58 Acoustic Cavitation Explained

10:35 Brew Ratio, Grind Size and Tamping

13:54 Is It Really Espresso?

16:34 Why the Brew Takes Three Minutes

18:04 Testing Different Coffees and Roast Levels

19:29 Brewing With Room-Temperature Water

21:40 The Blind Taste Test

28:24 What Happens to Aroma?

31:05 Extraction Yield and TDS

32:23 Less Bitterness and a Cleaner Aftertaste

33:48 The Energy-Saving Opportunity

35:41 APAX LAB

36:54 Can Ultrasonic Coffee Scale Up?

39:19 Patents and Commercialisation

42:04 Francisco’s First Coffee Project

44:39 The Team Behind the Research

45:08 Where to Find Francisco’s Work

Dr Francisco Trujillo, UNSW: unsw.edu.au/staff/francisco-trujillo

Ultrasonic espresso research: doi.org/10.1016/j.jfoodeng.2026.113193

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Proudly sponsored by:

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Riverina Fresh: riverinafresh.com.au

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