Insulin process

Claim 1

THE PROCESS OF RECOVERING INSULIN FROM INSULINCONTAINING PANCREAS GLAND MATERIAL, WHICH COMPRISES EXTRACTING THE GLAND MATERIAL AT A PH BETWEEN PH 3.5 AND PH 6.5 WITH AQUEOUS ALCOHOL IN THE PRESENCE IN THE EXTRACTION MIXTURE OF SALT OF THE CLASS CONSISTING OF SODIUM CHLOIDE, CALCIUM ACETATE, AND AMMONIUM CHLORIDE, USING ALCOHOL HAVING NOT MORE THAN TWO CARBON ATOMS AND IN A CONCENTRATION AND AMOUNT TO PRODUCE IN THE RESULTING EXTRACT AN ALCOHOL CONCENTRATION BETWEEN ABOUT 45% AND ABOUT 75%, AND USING SALT IN AN AMOUNT TO PRODUCE AT LEAST HALF SATURATION OF THE EXTRACT, CONCENTRATING THE EXTRACT TO PARTIALLY REDUCE THE ALCOHOL CONTENT THEREOF AND THEREBY DECREASING THE FAT-SOLVENT PROPERTY THEREOF WHILE SUBSTANTIALLY MAINTAINING THE INSULIN IN SOLUTION TREATING THE CONCENTRATED EXTRACT WITH A FAT SOLVENT TO REMOVE FAT THERFROM, CONCENTRATING THE DE-FATTED EXTRACT TO SUBSTANTIALLY REMOVE THE ALCOHOL THEREIN AND CAUSE THE SALT CARRIED OVER FROM SAID EXTRCTION TO BECOME EFFECTIVE SALT-OUT FROM THE SO-TREATED EXTRACT A SOLID INSULIN-CONTAINING MATERIAL, AND RECOVERING SUCH SOLID MATERIAL.