Abstract: An improved process for producing defatted heparin tissue is disclosed wherein frozen heparin-bearing tissue is particulated, thawed and warmed in a heat exchanger, fermented at temperatures ranging from about 60.degree.-85.degree. F. for 5 to 12 hours and subjected to azeotropic distillation and extraction to substantially remove water and fat. Putrefaction and odor are avoided, the tissue has improved uniformity in biochemical content, is lower in fat content and is capable of high heparin yields when processed according to known procedures. The defatted tissue is exceptionally permeable to heparin recovery solutions and heparin isolation is facilitated.

Abstract: An improved method of tempering frozen heparin-bearing animal tissue is disclosed wherein the frozen tissue is particulated, thawed and warmed in a heat exchanger and fermented at temperatures ranging from about 60.degree.-85.degree. F. for 5-12 hours. Putrefaction and odor are avoided; the tissue has improved uniformity in biochemical content and is capable of high heparin yields when processed according to known procedures. When the tempered tissue is defatted with an azeotropic solvent, more of the fat is removed and the defatted tissue is more permeable to heparin recovery solutions and heparin isolation is facilitated.