It's a derivative of an old saying from Bismarck, ca.1869: "Those who love sausage or legislation should NEVER watch either being made."
It has to do with compromises, components, and recipes.
That's Otto von Bismarck, by the way, first Chancellor of a unified Germany, speaking in Europe, not Harry Bismarck, who knew nothing about sausage or legislation.
Despite coming from an ultra-right winger, the saying itself has no political identity. And "pork" and other American hog washes are only indirectly relevant.
Reality, where the illiterate and the reactionary can't even think of going.