Kate Quilton heads to the world's biggest bread factory, finding out why some loaves fall to pieces at first contact with a knife, while others can happily survive a good spreading. Jimmy Doherty is in Turkey, investigating the intoxicating properties of the poppy seeds in bagels, while Matt Tebbutt sets out to find the secrets behind the writing on some cakes - is it the work of man or machine?

A special episode focusing on comfort food. Helen Lawal travels to Tanzania to discover the secrets behind vanilla ice cream, Kate Quilton discovers the surprising reason some of Britain's best-loved biscuits are punctured with holes, and Jimmy Doherty investigates how fish fingers are made and compares the prices for fresh and frozen pizzas. Plus, Matt Tebbutt reveals what pork pie jelly is actually for.