Having spent 20 or more years in the meat trade, our regular breakfast was a roll in lorne sausage, purely for quality control purpose of course. They can be made with either Pork or Beef or a mix of both. The reason that they are called Lorne is that the press that they are formed in is called a Lorne Pan, which is like a square loaf tin with a bottom that you can push out. Many of the products that are sold in multiple retailers are not made in the traditonal way but formed using a mechanical stuffer which is why many of them dry out round the outside and swell up in the middle.