What precisely is “ultrasonic espresso”?

Estimated studying time: 7 minutes

Key takeaways

• Ultrasonic espresso makes use of high-frequency sound waves to extract espresso-strength espresso from room-temperature water.
• Blind style assessments discovered no distinction between ultrasonic and conventional espresso.
• The brewing course of takes three minutes, far slower than standard espresso.
• Industrial ready-to-drink espresso manufacturing will profit greater than cafés.

Espresso is beloved the world over. It’s the second-most-consumed drink in Italy, and consumption in markets just like the US, which historically favour filter espresso, has reached file ranges, in keeping with the 2026 NCDT Specialty Espresso Report.

But each few years, espresso appears to get reinvented. The standard technique has actual drawbacks. It requires excessive temperatures and excessive strain, consumes a whole lot of vitality, produces important waste, and baristas typically battle with inconsistent extraction.

So researchers maintain trying to find “higher” methods to tug a shot. Now we have now “ultrasonic espresso” – however what’s it precisely?

You might also like our article revisiting extract chilling.

Espresso is a brief, concentrated drink brewed beneath excessive strain (round 9 bar) utilizing finely floor espresso. It’s extracted at a 1:2 water-to-coffee ratio for 25 to 40 seconds, leading to a wealthy, daring, and viscous beverage with a definite reddish-brown crema.

Invented within the early 1900s, espresso has stood the take a look at of time. However science needs to reinvent it.

Within the early 2000s, Montreal’s espresso scene turned synonymous with the allongé: a protracted shot of espresso extracted at a ratio between 1:4 and 1:6. The drink was developed in response to the rising recognition of lighter roast profiles and washed coffees. By grinding a lot coarser and extracting greater yields throughout the typical timeframe, it’s simpler to pinpoint fruity flavours.

20 years later, the Systematically Bettering Espresso research launched “turbo pictures”, extracted in 10 to 18 seconds by grinding coarser, utilizing smaller doses, and reducing strain. The concept was to make use of much less espresso, scale back waste, and enhance extraction effectivity and consistency.

Famend restaurant Noma additionally experimented with “Nomacanoes” in 2020 to enhance workflow and maximise extraction effectivity. Co-developed with Noma’s then-roaster Tim Wendelboe, the drink sits someplace between espresso and filter.

Most not too long ago, pre-batched espresso has divided specialty espresso. The observe entails pulling pictures prematurely, chilling them, and serving them to order for milk drinks. Advocates like Undertaking Zero declare it accelerates service and that prospects can’t style the distinction. Opponents argue it diminishes the craft of espresso.

Every innovation promised to unravel particular issues: pace, waste, consistency, flavour.

Now researchers on the College of New South Wales (UNSW) have added a brand new entrant to the record: “ultrasonic espresso”. Dr Francisco Trujillo and his workforce at UNSW’s College of Chemical Engineering have developed a course of that makes use of high-frequency sound waves to tug espresso-strength espresso from room-temperature water.

How does “ultrasonic espresso” work?

Dr Trujillo’s workforce used a transducer, a small metallic system, pressed in opposition to the aspect of the portafilter basket, producing ultrasonic sound waves that trigger it to vibrate quickly. 

The vibrations move by means of each the espresso grounds and water, triggering a phenomenon known as “acoustic cavitation”. Microscopic bubbles kind and collapse at pace, performing like tiny scrubbing brushes in opposition to the bottom espresso particles. This releases flavour compounds, oils, and caffeine into the water far quicker than room-temperature water would enable.

“We name it an ultrasonic espresso. It’s a unique course of, however you get the identical richness and focus of a standard espresso in beneath three minutes,” says Dr Trujillo. “Historically, espresso is made by forcing sizzling water by means of espresso beneath strain. However with ultrasound we will use room-temperature water as a substitute, decreasing vitality consumption by as much as 75%.”

This isn’t Dr Trujillo’s first time reimagining basic espresso drinks. His workforce beforehand developed a patented chilly brew system, compressing a course of that historically took 12 to 24 hours into about three minutes. 

However extracting ultrasonic chilly brew and espresso requires fully completely different approaches. 

“Crucial [factor] was the brew ratio… as a result of this helps guarantee the ultimate drink is concentrated and never too diluted,” Dr Trujillo says. “One other vital issue is how finely the espresso beans are floor. We discovered that by grinding finer we might extract the flavour extra quickly.

“We additionally experimented with how lengthy the sound waves have been utilized, as this will have an effect on each the focus and flavour of the espresso. What we discovered is that between two-and-a-half and three minutes is a candy spot for producing a balanced cup.”

So, what does “ultrasonic espresso” train us?

“Ultrasonic espresso” is unlikely to search out its method into espresso retailers, however the sensory outcomes are shocking.

UNSW ran a blind analysis with round 100 common espresso drinkers, fairly than educated tasters. Members have been served 4 varieties of espresso: conventional espresso, ultrasound-brewed espresso, conventional filter espresso, and ultrasound-brewed filter espresso, all cooled to the identical temperature and served in an identical cups. Every drink was rated on aroma, flavour, bitterness, and general liking.

The outcomes have been unambiguous for espresso. There was no important distinction between the standard and ultrasonic variations throughout any measure, and no clear desire both method. 

Curiously, individuals most popular the ultrasound-brewed filter espresso general, score its bitterness as extra nice than conventional filter espresso. “These findings confirmed that utilizing ultrasound didn’t hurt style, and in some circumstances even improved it, regardless of brewing at room temperature and with out the warmth usually related to espresso making,” says Dr Trujillo.

In the end, this implies that temperature and strain, two pillars of espresso extraction, aren’t strictly obligatory to satisfy the identical sensory targets, supplied adequate mechanical vitality comes from elsewhere. 

For an trade that treats the 9-bar, 90-something-degree extraction as customary, “ultrasonic espresso” is price considering – though style assessments from certified espresso professionals are obligatory.

The place the actual industrial worth lies

A standard espresso shot is prepared between 25 and 40 seconds, whereas “ultrasonic espresso” takes as much as three minutes. In any café, whether or not throughout a morning rush or a gradual afternoon, rising extraction time sixfold isn’t possible.

Dr Trujillo factors to the place the actual alternative lies. “There are firms that make espresso merchandise on an industrial scale, and we’re assured this ultrasound system will be scaled as much as meet their wants, delivering actual advantages by way of lowered processing instances and vitality use,” he says. “The 75% vitality saving is especially useful at that scale, and we’re additionally in a position to produce the espresso in a short time.” 

He provides that as a result of the method yields a concentrated, espresso-strength espresso, it may very well be used straight in ready-to-drink manufacturing or used as a focus for chilly brew and milk-based drinks.

Excessive vitality prices, water waste, and inconsistent extraction are actual issues, and researchers ought to maintain testing new methods to unravel them. UNSW’s work provides a reputable knowledge level: sound waves can substitute for warmth and strain with out sacrificing flavour, a minimum of in keeping with 100 blind tasters.

Not each resolution to a espresso downside ought to make its method behind the counter of a café. Some belong in a lab, refined additional, examined at scale, and ultimately licensed to producers who really profit.

Ultrasonic espresso is strictly this type of innovation, so don’t anticipate to see it in your native espresso store any time quickly.

Want extra leads in your espresso enterprise? Get in contact with PDG Media, our advertising and marketing company devoted to specialty espresso, right here.

Ultrasonic espresso FAQs

What’s ultrasonic espresso?
It’s a brewing technique developed by Dr Francisco Trujillo’s workforce on the College of New South Wales that makes use of high-frequency sound waves to extract espresso-strength espresso from room-temperature water in beneath three minutes.

Does ultrasonic espresso style completely different to conventional espresso?
In a blind take a look at with 100 common espresso drinkers, individuals confirmed no important desire between conventional and ultrasonic espresso throughout aroma, flavour, bitterness, and general liking.

Will ultrasonic espresso make its strategy to espresso retailers?
It’s extremely unlikely for use in cafés. It takes as much as three minutes per shot in comparison with 25 to 40 seconds for conventional espresso. Dr Trujillo sees extra worth in ready-to-drink espresso manufacturing.

Photograph credit: College of New South Wales

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