A research team at UNSW Sydney says it has brewed espresso at room temperature using sound waves instead of heat, while cutting energy use by up to 75% compared with conventional machines, according to an announcement on 1 June 2026 and a peer‑reviewed paper in the Journal of Food Engineering.
In tests cited by Daily Coffee News, producing three beverages at matched strength over 20 minutes, the prototype ultrasonic system consumed 0.020 kWh of electricity, compared with 0.0823 kWh for a conventional single‑group espresso machine. The same report notes that this means the ultrasonic brewer used about 24.3% of the energy of the traditional machine, aligning with the UNSW Newsroom claim of a 75% reduction.
Lead researcher Dr Francisco Trujillo, a senior lecturer in the School of Chemical Engineering at UNSW Sydney, described the process as “an ultrasonic espresso,” explaining that it is “a different process, but you get the same richness and concentration of a normal espresso in under three minutes.” In the same UNSW statement he contrasted the approach with conventional brewing, saying that “traditionally, espresso is by forcing hot water through coffee under pressure. But with ultrasound we can use room‑temperature water instead, reducing energy consumption by up to 75%.”
The technology relies on acoustic cavitation, in which tiny bubbles form and collapse in the brew water, creating micro‑jets that fracture coffee particles, according to UNSW’s description of the work. Earlier cold‑brew research by the same group, published in Ultrasonics Sonochemistry and summarized by the authors, used a 38.8 kHz ultrasound frequency and reduced cold‑brew extraction times from 24 hours to under three minutes while increasing extraction yield, indicating a broader program of applying sonochemistry to coffee beverages.
Extraction data for the new espresso‑style system reported by Daily Coffee News show that at a fine grind size of approximately 325 microns, the ultrasonic brewer achieved an extraction yield of 18.03%, placing it inside the Specialty Coffee Association’s commonly cited optimal range of 18–22%. Without ultrasound, extraction yield at the same grind setting was 16.26%, according to the same source. Italian outlet Futuroprossimo reported that the resulting beverage had a total dissolved solids concentration of 9–10%, which it described as the lower limit of the SCA’s ideal yield range.
On the sensory side, UNSW’s announcement states that when the team served ultrasonic espresso in a randomized blind test to 100 regular coffee drinkers, they could not tell it apart from a conventional espresso. Futuroprossimo gives further details, noting that the panel included 58 men and 42 women aged between 18 and 60, and reporting that the participants “could not reliably distinguish” between the two preparations. For filter‑style coffee, an article by Trujillo in The Conversation says the ultrasound version was actually preferred overall, with bitterness rated more pleasantly.
In a LinkedIn commentary on the work, co‑researcher Nikunj Naliyadhara, a food scientist and PhD candidate at UNSW, argued that the approach “embeds efficiency into the process itself, where outcomes can be measured, verified, and reproduced rather than simply asserted,” positioning the energy savings as an example of process‑level sustainability. An article in The Conversation adds that substituting thermal energy with acoustic energy in industrial food processing can significantly reduce operating costs, carbon emissions and processing times for ready‑to‑drink (RTD) coffee manufacturers.
The UNSW team says it is now seeking partnerships with commercial espresso machine manufacturers and industrial beverage companies to commercialize both the espresso‑style system and larger‑scale sonoreactors. According to UNSW’s newsroom, potential applications include bottling room‑temperature concentrates directly or shipping concentrates for dilution closer to consumption, which the university notes can save on logistics volume and energy use. Futuroprossimo reports that Trujillo estimates a [UNVERIFIED] 3–7 year window for adoption in the RTD segment, while describing the timeline for cafés and home kitchens as “much more uncertain.”
Naliyadhara’s LinkedIn post frames these developments as part of a wider move to shift sustainability from corporate reporting into core manufacturing methods, and The Conversation and ZMEScience both highlight ultrasonic coffee as an example of how acoustic processing can cut energy use in beverages, tying the UNSW prototype directly to broader efforts to lower the energy footprint of coffee production.
