3. Sausages

How a factory in North Yorkshire produces 625,000 sausages a day, using machines that can fill 600 sausages in a minute. How low and slow shallow frying delivers the best combination of flavour, moistness and succulence. How veggie protein is created from a tiny speck of natural fungus. How a 'meat sock' is the secret to wrapping a Scotch Egg every three seconds. How German bratwurst became top dog in America, and how German immigrant Charles Feltman originated the hot dog. Cooking up a 2,000-year-old recipe for sausages. How the Romans contributed by importing pepper, bay leaves and other spices that spike modern sausages.