Researchers from the University of Queensland and the University New South Wales have devised a new method for delivering a quality cold brew coffee in under three minutes.

The researchers have determined that their trained sensory panel tastings proved that the machine achieved a taste profile very similar to either a traditional cold brew or an espresso in the same amount of time it takes to brew a hot espresso.

Customized ultrasonic coffee brewing machine. a) Photograph of the machine. b) Schematic of the parts for the ultrasound transmission into the coffee basket. c-f), Photographs of the portafilter (with corresponding window), filter basket, transducer, and the horn, respectively. Source: Ultrasonics Sonochemistry (2024). DOI: 10.1016/j.ultsonch.2024.106885

To create the machine, the researchers superimposed their own patented sound transmission system on an existing coffee machine model. The system reportedly connected a bolt-clamped transducer with the brewing basket using a metallic horn, thereby transforming the coffee basket into an ultrasonic reactor.

The team concluded that the ultrasound process expedited the extraction of the oils, flavors and aroma of the ground coffee.

"We are very excited about developing this technology, which can be used by companies that already manufacture coffee machines, so consumers will be able to enjoy a 3-minute ultrasonic cold brew at home. This also opens the door for coffee shops and restaurants to produce on-demand brews comparable to 24-hour cold brews, supplying the rising demand while eliminating the need for large semi-industrial brewing units and extensive refrigeration space," the researchers added.

An article detailing the team’s work, “Coffee brewing sonoreactor for reducing the time of cold brew from several hours to minutes while maintaining sensory attributes,” appears in the journal Ultrasonics Sonochemistry.