GB625873A - Method of preparing gelatine - Google Patents

Abstract

Gelatine is prepared by treating a gelatine-containing material at an elevated temperature with an aqueous solution of ammonia or a non-cyclic amino compound containing not more than three carbon atoms in the molecule, and separating the gelatine from the solution. The gelatine-containing material, e.g. fresh, dried or salted hides, raw, degreased or acidulated bones, sinews, feet, or other parts of animals, are preferably reduced to pass a 50 mesh B.S. sieve, and are treated with a solution of preferably 10 - 30 per cent concentration of ammonia or an aliphatic amine, such as methylamine, dimethylamine, ethylamine, ethylene diamine, ethanolamine, propanolamine or propylene diamine, at a temperature of about 130 DEG F. The pH is maintained at 9 - 10 by buffering salts such as ammonium carbonate, acetate, chloride, sulphate, acid phosphate, citrate or tartrate. The gelatine is removed by (a) evaporating under reduced pressure and adjusting the pH to 7; (b) salting-out, preferably at a pH of 1 - 4; this could be accomplished by adding acid to neutralize the ammonia or amine, or, if a buffering-salt has been used, by adding acid to reduce the pH; or (c) by precipitation by adding an organic solvent in which gelatine is insoluble, e.g. acetone or ethyl alcohol. The gelatine is redissolved if necessary and the solution is filtered, and chilled and the gelatine obtained is washed and dried.