Reduced molecular weight native gellan gum

• US 6,242,035 B1
• Filed: 11/23/1998
• Issued: 06/05/2001
• Est. Priority Date: 11/23/1998
• Status: Expired due to Fees

• Current Assignee: Cp Kelco (JM Huber Corporation)
• Original Assignee: Cp Kelco (JM Huber Corporation)
• Inventors: Clark, Ross, Morrison, Neil, Burgum, Dan, Talashek, Todd, Chen, You-Lung
• Primary Examiner(s): HENDRICKS, KEITH D
• Application Number:
  US09/197,644
• Time in Patent Office: 925 Days
• Field of Search: 536/114, 536/123.1, 536/126, 536/123, 536/124, 252/315.01, 426/573
• US Class Current: 426/573
• CPC Class Codes: C08B 37/0024 beta-D-Glucans; (beta-1,3)-D-Glucans, e.g. paramylon, coriolan, sclerotan, pachyman, callose, scleroglucan, schizophyllan, laminaran, lentinan or curdlan; (beta-1,6)-D-Glucans, e.g. pustulan; (beta-1,4)-D-Glucans; (beta-1,3)(beta-1,4)-D-Glucans, e.g. lichenan; Derivatives thereof
• CPC Class Codes: C08B 37/006 Heteroglycans, i.e. polysaccharides having more than one sugar residue in the main chain in either alternating or less regular sequence; Gellans; Succinoglycans; Arabinogalactans; Tragacanth or gum tragacanth or traganth from Astragalus; Gum Karaya from Sterculia urens; Gum Ghatti from Anogeissus latifolia; Derivatives thereof
• CPC Class Codes: C08L 5/00 Compositions of polysaccharides or of their derivatives not provided for in groups C08L1/00 or C08L3/00

Abstract

This invention provides reduced molecular weight gellan gums. The reduced molecular weight gellan gums of this invention generally have a weight average molecular weight less than about 1.7×10⁶, and typically in a range of about 1.2×10⁶ to about 9.3×10⁵. This invention also provides compositions, e.g., solutions and gels, comprising reduced molecular weight gellan gums. The reduced molecular weight gellan gums of this invention may be prepared by any method which reduces the molecular weight of polymers. Such methods include homogenization, sonication, radiation, oxidation and hydrolysis.

Claims

1. A reduced molecular weight gellan gum comprising tetrasaccharide repeat units of the formula:

wherein the gellan gum has a weight average molecular weight between about 1.7×

10⁶ and about 4.0×

10⁵ as measured by Size Exclusion Chromatography/Multiple Angle Laser Light Scattering.

2. The gellan gum of claim 1, wherein the weight average molecular weight of said gellan gum is less than or equal to about 1.2×

10⁶ as measured by Size Exclusion Chromatography/Multiple Angle Laser Light Scattering.

3. The gellan gum of claim 1, wherein the weight average molecular weight of said gellan gum is between about 1.2×

10⁶ and about 9.3×

10⁵ as measured by Size Exclusion Chromatography/Multiple Angle Laser Light Scattering.

4. A composition comprising:

(a) a reduced molecular weight gellan gum comprising tetrasaccharide repeat units of the formula;

wherein the gellan gum has a weight average molecular weight between about 1.7×

10⁶ and about 4.0×

10⁵ as measured by Size Exclusion Chromatography/Multiple Angle Laser Light Scattering; and

(b) water.

5. The composition of claim 4, wherein the weight average molecular weight of said gellan gum is less than or equal to about 1.2×

10⁶ as measured by Size Exclusion Chromatography/Multiple Angle Laser Light Scattering.

6. The composition of claim 4, further comprising a gelling salt.

7. The composition of claim 6, wherein said gelling salt is selected from the group consisting of a calcium salt, a potassium salt and a sodium salt.

8. The composition of claim 7, further comprising a sequestrant.

9. The composition of claim 8, wherein said sequestrant is sodium citrate.

10. The composition of claim 7, wherein said gelling salt is a calcium salt.

11. The composition of claim 7, further comprising a fluid food product.

12. The composition of claim 11, wherein said fluid food product is selected from the group consisting of confectionery jellies, jams, jellies, dessert gels, icings, non-dairy frozen toppings, bakery fillings and dairy products.

13. A process for preparing a reduced molecular weight gellan gum comprising tetrasaccharide repeat units of the formula:

wherein the qellan gum has a weight average molecular weight between about 1.7×

10⁶ and about 4.0×

10⁵ as measured by Size Exclusion Chromatography/Multiple Angle Laser Light Scattering, said process comprising;

(a) hydrating the gellan gum in water; and

(b) reducing the molecular weight of said gellan gum whereby reduced molecular weight gellan gum is produced.

14. The process of claim 13, wherein the weight average molecular weight of said reduced molecular weight gellan gum is less than or equal to about 1.2×

10⁶ as measured by Size Exclusion Chromatography/Multiple Angle Laser Light Scattering.

15. The process of claim 13, wherein the molecular weight of said native gellan gum is reduced by a treatment selected from the group consisting of homogenization, sonication, radiation, oxidation and hydrolysis.

16. The process of claim 15, wherein said treatment is homogenization.

17. The process of claim 13, further comprising the step of reducing the molecular weight of said reduced molecular weight gellan gum.

18. The process of claim 17, wherein the molecular weight of said reduced molecular weight gellan gum is reduced by a treatment selected from the group consisting of homogenization, sonication, radiation, oxidation and hydrolysis.

19. The process of claim 18, wherein said treatment is homogenization.

20. A composition comprising:

(a) a reduced molecular weight gellan gum comprising tetrasaccharide repeat units of the formula;

wherein the gellan gum has a weight average molecular weight between about 1.7×

10⁶ and about 4.0×

10⁵ as measured by Size Exclusion Chromatography/Multiple Angle Laser Light Scattering;

(b) water;

(c) a gelling salt; and

(d) a sequestrant, wherein said composition is a gel.

21. The composition of claim 20, wherein the weight average molecular weight of said reduced molecular weight gellan gum is less than or equal to about 1.2×

10⁶ as measured by Size Exclusion Chromatography/Multiple Angle Laser Light Scattering.

22. The composition of claim 21, wherein said gelling salt is selected from the group consisting of a calcium salt, a potassium salt and a sodium salt.

23. The composition of claim 22, wherein said gelling salt is a calcium salt.

24. The composition of claim 23, wherein said sequestrant is sodium citrate.

25. The product obtained by the process comprising:

(a) hydrating gellan gum comprising tetrasaccharide repeat units of the formula

in water; and

(b) reducing the molecular weight of said gellan gum to between about 1.7×

10⁶ and about 4.0×

10⁵ as measured by Size Exclusion Chromatography/Multiple Angle Laser Light Scattering.

26. The product of claim 25, wherein the molecular weight of said native gellan gum is reduced by a treatment selected from the group consisting of homogenization, sonication, radiation, oxidation and hydrolysis.

27. The product of claim 26, wherein said treatment is homogenization.