Gelatin is generally refined from animal substances, so gelatin is also called "animal glue". Manufacturers boil cow and pig bones and skin in furnaces about 70 feet high to extract the collagen, then soak the residue.

When the warm gelatin aqueous solution cools, its viscosity gradually increases. If the concentration is large enough and the temperature is low enough, the gelatin aqueous solution will transform into a gel. Gelatin gel is a solid-like substance that retains its shape and is elastic. Gelatin gel can reversibly transform into a solution state after being heated. This is an unparalleled property of gelatin.

The stable gel strength value can be measured by cooling the gelatin solution at low temperature until gelation occurs and aging it at a certain low temperature for a certain period of time. The gel strength of gelatin is related to the molecular weight and distribution of gelatin, amino acid composition and process. Gelatin for different uses also requires different gel strengths.

The freezing of a gelatin solution and its subsequent changes in the gel network are caused by the partial return of the disordered gelatin molecules in the solution to the collagen structure. A more extensive reversion to collagen is induced and produced in a very homogeneous dilute solution of gelatin. This is also a reversal process that is essentially similar to the gel formation mechanism. It is called "refolding", but due to the dispersion of gelatin molecules , complex chemical compositions and their very different concentrations. During the renaturation process, the components of gelatin play different roles.

Gelatin production method:

Gelatin production by acid method mainly consists of three processes, from the collection and preservation of raw materials to the pretreatment of raw materials skin and bones in various ways. It is the pre-process part of the development of gelatin technology. The degradation of collagen, that is, the extraction of gelatin, is the second process part and is also a key part that affects the yield. The filtration, evaporation, sterilization, and drying of gelatin constitute the post-process part of gelatin technology. .

The production of gelatin by acid method and alkali method usually refers to the different chemical treatment methods between the raw material pre-process of gelatin and the gel extraction process. Acid method gelatin mainly uses single acids or compound acids such as hydrochloric acid, sulfuric acid, phosphoric acid, lactic acid, citric acid, acetic acid, etc. to expand the raw materials in the previous steps, and further uses weak acids or strong acids to destroy intermolecular cross-links and break molecular bonds, so that the polypeptides Dissolved in acid aqueous solution, it is also called gum extraction.

In the process of preparing gelatin by the alkaline method, the collagen-containing raw materials are first pre-treated by liming, washing and degreasing. After the raw materials are pre-treated, the fat content is low, and the main component is collagen. Lime or sodium hydroxide and collagen are gradually degraded into a polypeptide mixture with uneven molecular weight under certain temperature conditions. The polypeptide solution undergoes a series of treatments such as concentration, dehumidification and drying to obtain a solid powder. The alkaline process is capable of producing high quality gelatin in terms of product yield, nature and purity.

The above content refers to Baidu Encyclopedia-Gelatin