The most distinctive product in modern beverage retailing, which was the subject of a very sharp rise and then crash in its home country, continues to spread in London. Bubble Tea is a curious drink devised in Taiwan, in which either fruit-flavoured herbal mixes or milky teas are served with chewy tapioca balls at the bottom of the cup.

The product first came to light in Taiwan in the 1980s, and was the subject of a retail craze there in the late 1990s, when bubble tea cafés sprung up at a quite astonishing rate – so fast that the market became saturated, and some families who had invested in cafés lost everything.

The drink reached London in April of this year, when Assad Khan, a former New York investment banker, launched Britain’s first specialist bubble tea house in Soho.  His Bubbleology became successful at a speed that surprised even the founder, and he is now to expand by opening in the chic Harvey Nichols store, probably next month.

The development of the drink through the British café-bar sector is likely to be made difficult by the very problem that Assad Khan faced last year – it is difficult to source the product here.  He solved that by returning to Taiwan to find suppliers and be trained in making the drink.

A bubble tea in Harvey Nichols will be priced at £3.75.