IE44171B1 - Novel process for producing gelatin and its application - Google Patents

Description

This inventioh relates to a process for producing gelatin.

Patent No. 33729 describes the production of an enzymatic mixture which has the ability to cause in vivo a change in the viscosity of biological fluids, namely intestinal mucus, bronchial mucus and mucus of the cervix. This enzymatic mixture which alters the viscosity to an optimum value is produced from broths of certain streptomyces, especially streptomyces fradiae.

The present invention is based on the observation that certain enzymatic mixture described in British Patent No. 1,307,516 may be used for the production of gelatin. For the purpose of the present invention it is preferred to use the enzymatic mixture obtained from broths of streptomyces fradiae and more especially from streptomyces fradiae No. 2019 and No. 1998 (from the collection of the Museum d-Histoire Naturelle de Paris).

The present invention provides a process for producing gelatin which comprises treating ossein and/or meat cuttings with the enzymatic mixture obtained from streptomyces fradiae.

More precisely, by enzymatically treating ossein or meat cuttings, there is obtained an aqueous, suspension from which may be obtained a filtrate of a concentrated solution of proteins and an insoluble residue from which gela20 tin may be obtained in a pure form. After having separated the insoluble residue, the latter may be washed with hot water giving a soluble fraction consisting substantially of gelatin. The pure material is thereafter isolated and recovered according to known methods.

It is also possible to obtain a second crop of gelatin from the re25 maining insoluble residue either by repeated extraction or by renewed - 2 4 4 1 7 < enzymatic treatment when added to a further amount of ossein or meat cuttings.

The process of the present invention has the additional advantage of supplying gelatin in a high yield in contrast to the hitherto known chemical processes. Usually, the production of gelatin produces a yield of about 15% or less depending on the starting material used. With the present process, the yield amounts to about 70% or even more.

Without being bound with any theoretical consideration, it may be assumed that the enzymatic mixture from streptomyces fradiae attacks strongly the glycoproteinic moieties and the muccopolysaccharidic moieties linked to the collagen and consequently the amount of gelatin produced is far superior to that generally obtained by known chemical processes.

Moreover, the gelatin obtained is of high quality and may be recovered without any need for additional treatment which is time and money consuming, as usually required by known methods. The gelatin has a very low content of mineral matter as ascertained from the small amount of ash, generally lower than 1%. The cost of the process is accordingly greatly decreased.

According to the process of the present invention, the enzymatic treatment may be carried out in a homogeneous or in a heterogeneous medium. The medium is preferably an aqueous medium.

According to preferred features of the process :the enzymatic treatment is carried out at a temperature of from 10° to 50°C, more preferably from 15 to 25°C; the enzymatic treatment is carried out for a period of from 30 minutes to 25 hours depending on the raw material used, and more preferably for a - 3 4 4171 period of from 17 to 20 hours; the enzymatic treatment is carried out at a pH of from 3 to 9 and more preferably from 4 to 5; the gelatin is recovered by filtration or centrifugation of the reaction mixture; the gelatin is recovered by extracting the insoluble residue with hot water; the temperature of the water may be from 70 to 90°C; the gelatin is extracted from the insoluble residue by contacting the insoluble residue with hot water for a period of from 30 to 90 minutes; the gelatin is isolated by evaporation to dryness of the aqueous extracts Under reduced pressure, by lyophilisation or by atomization; the enzymatic mixture is that obtained by concentrating the broths of streptomyces fradiae strain 2019 as previously described.

The resulting gelatin finds many uses in the food industry, as a gelling agent in canned foods, in sweets and in jams. It may also be used in the pharmaceutical industry to produce pharmaceutical compositions containing gelatin, for example injectable solutions of gelatin. It may further be used as a binder in the production of tablets or micro-granules.

In addition, the soluble fraction of the reaction mixture usually contains from 10 to 2055 of soluble matter which may be recovered by evaporating or atomizing or lyophilizing the aqueous solution to dryness. The resulting dry residue may be used as an animal or human foodstuff. It has a high content in proteins. It may be incorporated in premixes or in biscuits.

The following Example illustrates the invention. - 4 * <31 71 EXAMPLE Step A The starting raw material may be ossein, scraps or cuttings of meat. They are previously washed but this is not essential. They are previously mashed then suspended while stirring in the aqueous solution or suspension of the enzymatic mixture of streptomyces fradiae No. 2019.

The quality of the water is unimportant; it may be distilled water, deionized water or tap water without any influence on the performance of the enzymatic reaction.

The reaction mixture is kept stirred and the pH is adjusted between 4 and 5, which seems to be optimal. From time to time, the pH is adjusted so that it remains within these limits.

The reaction mixture is kept at a temperature of 20°C ± 5°C for 17 hours while maintaining stirring. After this time, the insoluble matter is suction-filtered off and washed three times with cold water. The filtrate can be evaporated to dryness and used as a human or animal foodstuff.

The insoluble residue is suspended under gentle stirring in hot water preferably at 80 to 90°C in order to destroy the enzymatic mixture and to dissolve as much gelatin as possible each time. After one hour of contact the suspension is suction-filtered, the insoluble matter is dried and the aqueous phase recovered and combined with the filtrate.

These aqueous solutions are clarified and decoloured by adding a small amount of charcoal then filtered and evaporated off under vacuum.

The dry residue is a very pure gelatin. The insoluble residue from - 5 441*7 i the filtration is then suspended in hot water under the same conditions. After one hour, the solution is separated, the insoluble residue washed with hot water and the washings combined with the filtrate.

The aqueous solution is evaporated under reduced pressure and a 5 second crop of gelatin is recovered.

Step B To the remaining insoluble residue from Step A, a determined weight of ossein or of scraps is added. The whole mixture is taken up in water at 20°C ± 5° and a further amount of enzymatic mixture is added. The mixture is maintained under stirring and the pH is adjusted between 4 and . The reaction is carried out for 17 hours as in step A and the insoluble residue extracted as described in step A.

In this manner, the whole amount of ossein is transformed into gelatin. The treatment may be repeated as many times as necessary until no further gelatin is produced.

The enzymatic mixture from streptomyces fradiae has the following analytical specification: Total proteolytic activity Proteolytic activity not inhibited by Inipho1 Proteolytic activity not inhibited by the trypsin-inhibitor from soya beans Content of proteins (Lowry's method) 7000 U. Anson/mg 5160 U. Anson/mg 5570 U. Anson/mg 45.7% on dry material - 6 Enzyrao electrophoresis: main presence of component 2 as defined by Morihara and coll (Bio Chim. Biophys. Acta 139 (1967) 382).

Claims (12)

1. A process for producing gelatin which comprises treating ossein and/or meat cuttings with the enzymatic mixture obtained from streptomyces fradiae, and recovering gelatin from the resulting insoluble residue. 5

2. A process according to Claim 1, wherein the enzymatic mixture is that obtained from streptomyces fradiae No. 2019 or streptomyces fradiae No. 1998.

3. A process according to Claim 1 or Claim 2, wherein the enzymatic treatment is carried out in an aqueous medium. 10

4. A process according to any one of Claims 1 to 3, wherein the enzymatic treatment is carried out at a temperature of from 10 to 50°C.

5. A process according to any one of Claims 1 to 4, wherein the enzymatic treatment is carried out for from 30 minutes to 25 hours.

6. A process according to Claim 5, whrein the enzymatic treatment is 15 carried out for from 17 to 20 hours.

7. A process according to any one of Claims 1 to 6, wherein the enzymatic treatment is carried out at a pH of from 3 to 9.

8. A process according to any one of Claims 1 to 7, wherein the gelatin is recovered by separating the insoluble residue from the reaction mixture, washing the insoluble residue with hot water evaporating the extract and drying the residue.

9. A process according to any one of Claims 1 to 7, wherein the filtrate from the reaction mixture is evaporated to dryness and the residue is purified to supply a concentrated solution of proteins.

10. A process according to Claim 1 carried out substantially as described in the Example herein. - 8 Π. Gelatin whenever obtained by a process according to any one of Claims 1 to 8 and 10.

11.

12. A protein concentrate whenever obtained by a process according to Claim 9 or Claim 10.