Gelatin is obtained from selected pieces of calf and cattle hides, de-mineralized cattle bones (ossein) and porkskin. Contrary to popular belief, hoofs, horns, hair, feathers or any keratin material is not a source of gelatin.
There are two types of gelatin - Type A, derived from acid processed materials, primarily porkskin; and Type B, derived from alkaline or lime processed materials, primarily cattle or calf hides and ossein.
Type A Gelatin is produced from fresh or frozen porkskin by washing with water and soaking in dilute acid. Acidified skins are washed free of acid and soluble proteins. Treated porkskins are placed in extraction kettles and partially hydrolyzed with successive portions of hot water. The dilute solution is filtered and evaporated. Concentrated solutions are chilled to a gel which is then carefully dried with filtered and conditioned air in drying tunnels or in continuous dryers to a solid containing approximately ten percent moisture. The dried gelatin is then ground and tested for grade and quality.
Calf skin or hide trimmings, sources of type B gelatins, are first washed and then treated with lime for one to three months. Limed skins are washed and neutralized with dilute acid. After this conditioning, the skin stock is transferred to kettles and heated with successive portions of hot water. A partial hydrolysis of the collagen occurs, resulting in extracts which are dilute solutions of gelatin. From this point on, the extracts of Type B gelatin are processed in a manner similar to Type A described above.
Ossein gelatin is derived from degreased, hard bones which are washed and then leached with repeated portions of dilute hydrochloric acid. The acid reacts with the mineral contents of the bone, which are removed in the acid solution, and a sponge-like material, called ossein, resins. This organic portion of the bone represents about 25 percent of the original bones. The ossein, washed free of acid, may then be either dried for storage, or limed immediately. Subsequent treatment of ossein, after liming, follows the procedure outlined above for the production of gelatin from calf skin.
All grades of gelatin are prepared under the most rigid sanitary conditions. Either stainless steel or glass equipment is used in the cooking and finishing processes.
Gelatin should be stored in a cool, dry place. This product can be kept for 3 years as long as containers are kept tightly closed. Use good manufacturing practices.
Each batch of gelatin is tested to evaluate its various characteristics. Official methods of testing have been developed by the Gelatin Manufacturers Institute. The procedures used are variations of those outlined in Association of Official Agricultural Chemists (AOAC) "Methods of Analysis" and United States Pharmacopoeia / BAM (Bacterological analytical manual).
Gelatin is usually tested for gel strength (bloom grams), viscosity, pH and moisture.
Consult our specification sheets for the technical information on the gelatin you may desire.