Fibrinolysin

An alternative term for plasmin: the enzyme that dissolves blood clots by breaking down fibrin. In dairy science, plasmin in milk can degrade casein during storage, affecting the quality of UHT milk and cheese, a genuine quality concern in milk processing. Plasmin originates as plasminogen in milk and is activated by heat-stable plasminogen activators that survive pasteurisation; UHT treatment paradoxically increases activity by denaturing inhibitors. The result — age gelation and bitter peptides in long-life milk — is managed by raw-milk quality, since mastitic milk carries far higher plasmin levels.