"Playing the offended liverwurst" is a proverbial German expression used to mock a person who has offended is. The pouting person is assumed to be offended for no reason at all.
This proverb can be traced back to the Middle Ages. Indeed, in the Middle Ages, people believed that in the Liver the temperament sits. So anyone who was offended and angry had an offended liver.
The background to this saying is the humoral-pathological or -physiological conception of the medicine of antiquity and the Middle Ages that the liver is the seat (or storage place) of the life fluids and thus causal for the temperaments. Especially the anger was assumed to be located here. This idea persisted in the German language until the 18th century. The same background also has the saying "Something free or Fresh from the liver to say away," which means to speak openly, unreservedly and frankly. The saying that someone is "offended liver sausage" is clearly close to the "offended liver sausage. "A Louse Runs Over Your Liver", on. A trifling occasion (the little louse) that causes annoyance and anger.
The "Sausage" was attached to the proverb "Insulted liver sausage" only when the idea around the liver as the seat of the feelings was lost. So it became the Basis of a narrative the liver sausage. In this tale cooked a Butcher Sausages and took all Sausages that do not cook so long had to, first from the pot. Since the Liver sausage had to cook longer than all the other sausages, she felt left behind here. So she finally stayed alone and offended in the pot until she burst with rage at the end.