How is caffeine removed from coffee? What puts the chew into chewing gum? How are the calories counted in diet bread? Jimmy Doherty visits Brazil to find out more about coffee beans and to try to find a naturally grown caffeine-free coffee. Kate Quilton heads to Finland to find out what makes chewing gum so chewy and if it is safe to swallow. At a giant chemical plant she learns that many of the ingredients found in some of our gums can also be found in car tyres and other unlikely products. Matt Tebbutt counts the calories in diet bread. It looks and tastes similar but how are the calories sliced off?