The particular optimal time period is dependent upon the fish species and the ease with which the gelatin is extractable therefrom. soaking the skins in an alkaline hydroxide containing solution such as a Ca(OH) 2 -containing limewater solution suspension for a period of time of between three to sixty days. Furthermore, gelatin extracted from fish is susceptible to an objectionable characteristic fish smell, associated, in part, with even small degrees of putrefaction.Ī. Fish, particularly species with high fat content, are highly susceptible to rapid bacteria development and putrefaction after only short time periods.

In particular, such methods do not allow for extraction prior to putrefaction of the fish.

However, the efficacious extraction methods, commonly utilized with the animal sources for gelatin, particularly the alkaline methods, for extended time periods, tend to result in unusable fish skins and swim bladders, with little, if any, extractable useful gelatin. In such methods the collagen rich fish skins (particularly of warm water fish species) and to a lesser extent, swim bladders, are treated, to form and extract gelatin. Methods for the extraction of gelatin from fish in particular fish having fins and scales (kosher fish), a more palatable source for orthodox Jews Moslems and many vegetarians, have been known for some years. Acid treatment followed by additional limewater treatment restores Bloom strength lost by excessively long initial limewater treatment. At concentrations above 100 gm of Ca(OH) 2 /liter of water/kg of fish skin and/or treatment time periods in excess of four weeks, Bloom strength dramatically decreases. For fish with easily extractable gelatin, such as Nile perch, soaking time is from 3 to 10 days with a concentration of Ca(OH) 2 /liter of water of about 15 gm. For fish with higher percentage of fat content, a minimum concentration is at least 50 gm of Ca(OH) 2 /liter of water/kg of fish skin to avoid putrefaction. Gelatin, having high Bloom or gel strength in excess of 300, is extracted from fish, with high yield, by pre-treating collagen rich fish skins with a limewater (Ca(OH) 2) solution suspension with a concentration of between 19 gm of Ca(OH) 2 /liter of water/kg of tilapia fish skin to 100 gm Ca(OH) 2 /liter of water/kg of fish skin for a period of time between ten to sixty days and optimally between two to four weeks. Y10S530/857- Fish fish eggs shell fish crustacea.Y10S530/855- Proteins from animals other than mammals or birds.Y10S530/00- Chemistry: natural resins or derivatives peptides or proteins lignins or reaction products thereof.Y10S- TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS AND DIGESTS.Y10- TECHNICAL SUBJECTS COVERED BY FORMER USPC.Y- GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS AND DIGESTS.C09H3/00- Isolation of glue or gelatine from raw materials, e.g.C09- DYES PAINTS POLISHES NATURAL RESINS ADHESIVES COMPOSITIONS NOT OTHERWISE PROVIDED FOR APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR.A23J3/00- Working-up of proteins for foodstuffs.A23J- PROTEIN COMPOSITIONS FOR FOODSTUFFS WORKING-UP PROTEINS FOR FOODSTUFFS PHOSPHATIDE COMPOSITIONS FOR FOODSTUFFS.A23- FOODS OR FOODSTUFFS TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES.Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.) Filing date Publication date Application filed by Individual filed Critical Individual Priority to US08/208,002 priority Critical patent/US5484888A/en Application granted granted Critical Publication of US5484888A publication Critical patent/US5484888A/en Anticipated expiration legal-status Critical Status Expired - Lifetime legal-status Critical Current Links

Original Assignee Individual Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.) Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.) Expired - Lifetime Application number US08/208,002 Inventor David Holzer Current Assignee (The listed assignees may be inaccurate. Google Patents US5484888A - Gelatin productionĭownload PDF Info Publication number US5484888A US5484888A US08/208,002 US20800294A US5484888A US 5484888 A US5484888 A US 5484888A US 20800294 A US20800294 A US 20800294A US 5484888 A US5484888 A US 5484888A Authority US United States Prior art keywords fish skins fish skins water days Prior art date Legal status (The legal status is an assumption and is not a legal conclusion.

Marshmallows fish gelatin