Food Unwrapped celebrates the May bank holiday with this sizzling Barbecue Special, lifting the lid on some of Britain's favourite al fresco foodstuffs. Jimmy Doherty's on a meaty mission, probing the difference between marinades and dry rubs, and what meats go best with each. Andi Oliver gets to grips with the increasingly popular halloumi- it's the perfect BBQ veggie alternative to meat, but why does it split in half when you pop it over the coals? Kate Quilton's  on a quest to work out what keeps your drinks coldest- bottles or cans? Jimmy's on the case of why certain fruits such as melon are ever-present in supermarket fruit salads, while others, such as strawberries, rarely get a look in. And Briony May Williams heads to Wales to solve the mystery of edible charcoal- what exactly is it, and could we simply chow down on the coals from our barbecue?