How to taste real ale like an expert

The British beer industry is undergoing something of a renaissance.

According to the Campaign for Real Ale, the number of brewers operating across the country has increased from 550 seven years ago, to 850 today.

Described as the world's biggest pub, the annual Great British Beer Festival is taking place at London's Olympia, showcasing hundreds of beers from around the UK and the world.

Roger Protz, the editor of the Campaign for Real Ale's "Good Beer Guide", explains the finer points of how to taste beer.

Video Journalist: John Galliver