In a railway arch in south London, pickers and packers are in a race against time to get fresh food to the door of Alastair Dean within 15 minutes of his order hitting an app.

Their company, Weezy, is part of a new army of European rapid delivery firms that, backed by billions of dollars of venture capital from Europe, the United States, China and Japan, are using electric bikes and scooters to deliver groceries.

They have placed a bet that demand for convenience will drive the next transformation in food retail and help crack the vice-like grip of the big supermarket stores which, in Britain, supply 95% of the country's groceries.