London - It's a claim which is bound to cause a stir among coffee lovers.
Experts say what you sip the drink from affects its flavour – with a rough cup leaving a bitter after-taste while the same coffee tastes sweeter from a smoother vessel.
Scientists in Brazil – the world’s biggest coffee producer – ran tests involving experts and regular drinkers. They found that the "haptic" – or touching – experience of what people were drinking from made a big difference. More than 230 people took part in the research, with half of them experts – including professional coffee graders.
They drank high-grade Brazilian coffee from a smooth porcelain cup and also used a mug made of white ceramic with a rough finish on the outer and inner walls. Both were a similar shape and weight.
Psychologist Dr Fabiana Carvalho said: "The coffee was perceived as sweeter when tasted from a smooth-surface cup. The coffee was rated as more acidic from the rough cup.’ She added: ‘These results demonstrate that haptic cues influence the judgment of basic tastes as well as mouth-feel attributes in specialty coffee.