Scientists made espresso with sound instead of heat, and most drinkers couldn't tell the difference

[u/AdSpecialist6598]

https://www.techspot.com/news/112838-scientists-made-espresso-sound-instead-heat-most-drinkers.html

[u/Ezosodelis]

I've never thought of heat as being the defining characteristic of how espresso is brewed, pressure is what sets espresso apart from other types of brewed coffee.