Alkaline pH-modified edible casein-based films and coatings, and method for the making thereof

Patent metadata

Field	Value
Publication number	US-10906950-B2
Application number	US-201715679431-A
Country	US
Kind code	B2
Filing date	Aug 17, 2017
Priority date	Aug 19, 2016
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

Improved casein-based films are produced by adjusting the pH of a film-production suspension. The film-production suspension may contain a casein source, a plasticizer, and optionally a strengthening additive. The adjustment of the pH may be accomplished by the addition of an alkaline additive, such as a base, to achieve a desired pH value. The improved casein-based films have improved physical properties as compared to those produced without a pH-adjusted film-production suspension at least in part due to the chemical and structural changes imparted by the change in pH.

First claim

What is claimed is:

1. A casein-based film, comprising:
a casein source;
a plasticizer; and
an alkaline additive,
wherein the film has a melting point temperature at 50% relative humidity of at least 60° C., and
wherein the alkaline additive is in an amount in excess of an amount necessary to convert all casein in the mixture to caseinate.

2. The casein-based film of claim 1 , wherein the film has a storage modulus, G′, at 50% relative humidity and 60° C., of at least 150 MPa.

3. The casein-based film of claim 1 , wherein the casein source is one of a caseinate, a fluid or dried milk product, milk protein concentrate, micellar casein concentrate, and a mixture thereof.

4. The casein-based film of claim 1 , wherein the plasticizer is one of glycerol, sorbitol, propylene glycol, polypropylene glycol, sucrose, and a mixture thereof.

5. The casein-based film of claim 1 , wherein the amounts of the casein source and the plasticizer are present in a ratio of casein source:plasticizer being 99:1 to 1:1.

6. The casein-based film of claim 1 , further comprising a strengthening additive.

7. The casein-based film of claim 6 , wherein the strengthening additive is one of a pectin, a polysaccharide, a pullulan-microbial polysaccharide, a dextrin, an oligosaccharides, a monosaccharide, a disaccharide, high fructose corn syrup, cellulose, hemi-cellulose, a gum or the constitutive sugar thereof, methylcarboxycellulose, gelatin, carrageenan, agar, an alginates, egg albumen, transglutaminase, tyrosinase, an aglycone, a glycoside, a chloride salt, a bicarbonates, a phosphate, one of vitamins A-K, milk fat, a polyunsaturated fat, a monosaturated fat, an omega-3 fatty acid, a conjugated linolenic acid, alpha linolenic acid, a phospholipid from milkfat, a lecithin, a sterol, soluble or insoluble plant fiber, a fiber gum, psyllium, flax seed, quince seed, an antioxidant, a carotenoid, and a mixture thereof.

8. The casein-based film of claim 6 , wherein the strengthening additive is present in an amount of 0.05% to 5% (w/w).

9. A method of producing a casein-based film, comprising:
producing a film-production suspension, the film-production suspension comprising a solvent, a casein source, and a plasticizer;
adjusting the pH of the film-production solution to at least ≥8.0;
creating a film from the pH-adjusted film-production suspension by drying; and
thereby obtaining a casein-based film.

10. The method of claim 9 , wherein the solvent is water.

11. The method of claim 9 , wherein the casein source is one of a caseinate, a fluid or dried milk product, a milk protein concentrate, a micellar casein concentrate, and a mixture thereof.

12. The method of claim 9 , wherein the plasticizer is one of glycerol, sorbitol, propylene glycol, polypropylene glycol, sucrose, and a mixture thereof.

13. The method of claim 9 , wherein the amounts of the casein source and the plasticizer are present in the film-production suspension in a ratio of casein source:plasticizer being 99:1 to 1:1.

14. The method of claim 9 , wherein the film-production suspension further comprises a strengthening additive.

15. The method of claim 14 , wherein the producing of the film-production suspension is performed by either:
(i) adding the plasticizer to the solvent to create a solvent-plasticizer suspension, then adding the casein source to the plasticizer-solvent suspension to create a solvent-plasticizer-casein suspension, then adding the strengthening additive to create the film-production suspension;
(ii) adding the plasticizer to the solvent to create a solvent-plasticizer suspension, then adding the strengthening additive to create a solvent-plasticizer-strengthening additive suspension, then adding the casein source to the solvent-plasticizer-strengthening additive suspension to create the film-production suspension; or
(iii) adding the strengthening additive to the solvent to create a solvent-strengthening additive suspension, then adding the casein source to the solvent-strengthening additive suspension to create a solvent-strengthening additive-casein suspension, then adding the plasticizer to the solvent-strengthening additive-casein suspension to create the film-production suspension.

16. The method of claim 14 , wherein the strengthening additive is one of pectin, a polysaccharide, a pullulan-microbial polysaccharide, a dextrin, an oligosaccharides, a monosaccharide, a disaccharide, high fructose corn syrup, cellulose, hemi-cellulose, a gum or the constitutive sugar thereof, methylcarboxycellulose, gelatin, carrageenan, agar, an alginates, egg albumen, transglutaminase, tyrosinase, an aglycone, a glycoside, a chloride salt, a bicarbonates, a phosphate, one of vitamins A-K, milk fat, a polyunsaturated fat, a monosaturated fat, an omega-3 fatty acid, a conjugated linolenic acid, alpha linolenic acid, a phospholipid from milkfat, a lecithin, a sterol, soluble or insoluble plant fiber, a fiber gum, psyllium, flax seed, quince seed, an antioxidant, a carotenoid, and a mixture thereof.

17. The method of claim 9 , wherein the adjusting the pH of the film-production suspension comprises adding an alkaline additive to the film-production suspension.

18. The method of claim 17 , wherein the alkaline additive is one of a monovalent hydroxide, a divalent hydroxide, and ammonium.

19. The method of claim 9 , wherein the adjusting the pH of the film-production suspension comprises adjusting the pH to at least ≥8.5.

20. The method of claim 19 , wherein the adjusting the pH of the film-production suspension comprises adjusting the pH to at least ≥9.0.

21. The method of claim 19 , wherein the adjusting the pH of the film-production suspension comprises adjusting the pH to at least ≥9.4.

22. The method of claim 9 , wherein the adjusting the pH of the film-production suspension comprises adjusting the pH to a value of about 8.5 to about 12.0.

23. The method of claim 9 , wherein the creating of the film from the pH-adjusted film-production suspension by drying comprises one of casting a film in mold, spraying, and dipping.

24. The casein-based film produced by the method of claim 9 .

Assignees

• Us Agriculture

Inventors

• Bonnaillie Laetitia
• Tomasula Peggy M

Classifications

• C08K2003/2206

  of calcium, strontium or barium · CPC title

• C08K5/053

  Polyhydroxylic alcohols · CPC title

• C08J2389/00

  Characterised by the use of proteins; Derivatives thereof · CPC title

• C08J5/18

  Manufacture of films or sheets · CPC title

• C08K3/22

  of metals · CPC title