Favourites: Squid and Chips, Kangaroo Meat, Pesto

Matt Tebbutt wonders why he never finds pearls in his seafood platters, so he visits China - the world's biggest oyster producers - to find out. Jimmy Doherty examines London dry gin, and hears about a threat to British juniper berries that could spell the end of gin's recent resurgence in popularity. Kate Quilton unearths the contents of herbal bedtime teas to establish if they really can help people nod off.