A method of preparing an aesculin sturgeon skin gelatin with antioxidant activity and Enterococcus faecalis detection ability includes: 1) mixing a sturgeon skin gelatin and distilled water in a ratio of 1:15-1:25 (w/v) at 50-70 C. and filtering to obtain a sturgeon skin gelatin solution; 2) adding aesculin and a glycerin solution to the sturgeon skin gelatin solution, stirring the resulted sturgeon skin gelatin solution at 30-50 C. for 30 minutes, and filtering; and 3) removing air bubbles from the sturgeon skin gelatin solution of step 2) under reduced pressure, placing the sturgeon skin gelatin solution on an acrylic glass, and drying the sturgeon skin gelatin solution at in a vented oven 25 C. and 45-55% relative humidity for 24 hours to obtain the aesculin sturgeon skin gelatin film.

A process for obtaining fish gelatin characterized because it comprises: (a) cleaning of fish skins; (b) washing of skins with water; (c) treating with diluted alkali solution with constant agitation; (d) washing of skins with water until the wash water is in a pH range between 6.8 and 7.2; (e) treating with diluted organic acid solution with constant agitation; (f) washing of skins with water until the wash water is in a pH range between 6.8 and 7.2 and subsequent runoff; (g) extracting gelatin by mixing the skins in an organic acid solution with a concentration of 0.2 to 0.3 weight percent by volume at a temperature of 55 to 65 C. and for 260 to 340 minutes; (h) filtering to remove skin debris and impurities; (i) drying; and (j) grinding.

A process for obtaining fish gelatin characterized because it comprises: (a) cleaning of fish skins; (b) washing of skins with water; (c) treating with diluted alkali solution with constant agitation; (d) washing of skins with water until the wash water is in a pH range between 6.8 and 7.2; (e) treating with diluted organic acid solution with constant agitation; (f) washing of skins with water until the wash water is in a pH range between 6.8 and 7.2 and subsequent runoff; (g) extracting gelatin by mixing the skins in an organic acid solution with a concentration of 0.2 to 0.3 weight percent by volume at a temperature of 55 to 65 C. and for 260 to 340 minutes; (h) filtering to remove skin debris and impurities; (i) drying; and (j) grinding.

A method of preparing an aesculin sturgeon skin gelatin with antioxidant activity and Enterococcus faecalis detection ability includes: 1) mixing a sturgeon skin gelatin and distilled water in a ratio of 1:15-1:25 (w/v) at 50-70 C. and filtering to obtain a sturgeon skin gelatin solution; 2) adding aesculin and a glycerin solution to the sturgeon skin gelatin solution, stirring the resulted sturgeon skin gelatin solution at 30-50 C. for 30 minutes, and filtering; and 3) removing air bubbles from the sturgeon skin gelatin solution of step 2) under reduced pressure, placing the sturgeon skin gelatin solution on an acrylic glass, and drying the sturgeon skin gelatin solution at in a vented oven 25 C. and 45-55% relative humidity for 24 hours to obtain the aesculin sturgeon skin gelatin film.

A gelatin or a chemically modified product thereof contains 10 to 50% by mass of a high-molecular weight component, and a low-molecular weight component in such an amount that a value obtained by subtracting a low-molecular weight component content from a high-molecular weight component content is greater than or equal to 0% by mass.

A gelatin or a chemically modified product thereof contains 10 to 50% by mass of a high-molecular weight component, and a low-molecular weight component in such an amount that a value obtained by subtracting a low-molecular weight component content from a high-molecular weight component content is greater than or equal to 0% by mass.

Provided is an enzymatic method of extracting high quality gelatin from collagen containing material.

Provided is an enzymatic method of extracting high quality gelatin from collagen containing material.