It was an ominous Thursday afternoon waay back in grade 6 when we had a class outing to the local meat packing plant. This was in Saskatoon, a prarie town and the plant had contracts to supply most of the supermarkets in western Canada with weenies.
The sight of the two "gentlemen" in surgical-white hipwaders shoveling in, uh... "stuff" into a floor mounted meat grinder grille is forever etched into my delicate, eggshell mind. I tried my best to forget it, but when viewing Pink Floyd's "the wall" several years later in grade 12, I had a relapse and just about tossed my cookies in the theater.
What's in the stuff? Mechanically de-boned meat. What that is, is a s/s conveyor belt that feeds bones through a chain whip. The chains flail at the bones and are then "combed" off, and the resulting sludge is further processed. The sludge has an added bonus of being already ground, (labour saving!) and it binds with other ingredients much better than just ground meat.
But, hey, what really is meat? Classic definition is muscle. Liver and kidneys are "offal", but a heart is a true muscle. Facial muscles and sphincter muscles aren't offal, and they're too good for dog food.
So there's some kind of meat, water, (usually ice) fat, salt, fake smoke flavour, maybe milk powder, and a bunch of sodium somethings. Fat and water and tissue make a great emulsion, which is what sausage is, an emulsion.
To make snausages, you'll need a meat grinder, of course, a food processor is nice, and a stuffer. Soak your lamb casings in water, and change the water several times. Grind your farce course, then fine, then in the food processor. Don't let it get warm or the emulsion will split. Load up the sausage casing onto the stuffer uhh..."tube" and tie a knot at the end. Load up the stuffer chamber with farce and try not to get any air in there. Start cranking and while stuffing, start making links by twisting the casing. Smoke or not to smoke, your call, then poach and then cool down. Reheat in your favorite way.