Culinary historian Michael Twitty says cultures have a right to the inherent value of their gastronomical production, and argues that by sharing our food traditions we remind ourselves that we are all one family, with one destiny. Twitty was speaking at the Observer Ideas festival 2014 at the Barbican in central London, part of Guardian Live, our series of events, debates, interviews and festivals exclusively for Guardian members. Find out about future Guardian Live events here