Trypsin is supplied as powder that, in solution, acts to break down protein into its constituent amino acids. The source is mammalian (porcine).
Although trypsin will act on many different forms of protein, we have found its action on casein in low-fat milk allows good observations to be made. By using a light meter or colorimeter connected to a datalogger, you can plot the different reaction rates as conditions such as temperature and pH are varied.
SOURCE: Porcine Pancreas