At the University of Oxford, Prof Charles Spence, head of the Crossmodal Research Lab, has studied how much your experience of coffee is shaped by the way it is presented. In Nespresso adverts, he observed, coffee is almost always displayed in a transparent glass, with a crown of light crema on top of the drink. “It starts to look almost like a pint of Guinness,” Spence said. “Coffee doesn’t come with the visual variation you get in tea or wine – it’s all pretty much the same colour, so perhaps you have to show it with the crema.” (The crema is key to the mythology of espresso. Legend has it that the Italian company Gaggia coined the term in the 30s, rebranding something customers had previously thought of as “scum” on the top of their drink as “caffe creme”, a coffee so fine it made its own froth.)
From a great Guardian longread on Nespresso.