Frozen chlorine dioxide-containing composition and methods related thereto

• US 6,328,909 B1
• Filed: 08/08/2000
• Issued: 12/11/2001
• Est. Priority Date: 02/18/1999
• Status: Expired due to Term

• Current Assignee: Ecolab USA Incorporated (Ecolab, Inc.)
• Original Assignee: Alcide Corp (Ecolab, Inc.)
• Inventors: Kemp, G. Kere, Kross, Robert D.
• Primary Examiner(s): ANTHONY, JOSEPH DAVID
• Application Number:
  US09/634,662
• Time in Patent Office: 490 Days
• Field of Search: 422/29, 422/37, 422/40, 422/28, 252/187.21, 252/187.23, 424/405, 424/409, 424/44, 424/661, 426/66, 426/67, 426/68, 426/320, 426/327, 426/331, 426/332, 426/333, 426/335
• US Class Current: 252/187.21
• CPC Class Codes: A23B 4/12 Preserving with acids; Acid fermentation
• CPC Class Codes: A23B 4/24 Inorganic compounds
• CPC Class Codes: A23B 7/10 Preserving with acids; Acid fermentation
• CPC Class Codes: A23B 7/157 Inorganic compounds
• CPC Class Codes: A23L 3/3508 containing carboxyl groups
• CPC Class Codes: A23L 3/358 Inorganic compounds
• CPC Class Codes: A61P 31/02 Local antiseptics

Abstract

A frozen chlorine dioxide-containing composition comprising a metal chlorite and a protic acid in a frozen aqueous matrix made by freezing a substantially chloride dioxide-free aqueous solution comprising a metal chlorite at a concentration ranging from about 0.0005% to about 0.5% by weight and a protic acid at a concentration sufficient to lower the pH of the aqueous solution to a value of about 1.8 to about 5.0. The frozen chlorine dioxide-containing composition has a chlorine dioxide concentration of more than about 3 ppm, while the aqueous solution prior to freezing has a chlorine dioxide concentration less than about 3 ppm. The frozen chlorine dioxide-containing composition is used to disinfect substrates by contacting the same with the frozen chlorine dioxide-containing composition. Suitable substrates include food intended for human or animal consumption, such as meat, fish and poultry.

Claims

1. A frozen chlorine dioxide-containing composition prepared by the following steps:

1) preparing an aqueous solution comprising about 0.0005% to about 0.5% by weight of metal chlorite and a sufficient protic acid concentration to lower the pH of the aqueous solution to a value of about 1.8 to about 5.0, and wherein said prepared aqueous solution has a chlorine dioxide concentration of less than about 3 ppm at all times prior to freezing; and

2) freezing said prepared aqueous solution comprising metal chlorite and protic acid to form a frozen aqueous matrix composition wherein said formed frozen chlorine dioxide containing composition has a chlorine dioxide concentration of more than about 3 ppm.

2. The composition of claim 1 wherein the metal chlorite is an alkali or alkaline earth chlorite.

3. The composition of claim 1 wherein the metal chlorite is sodium or potassium chlorite.

4. The composition of claim 1 wherein the metal chlorite is sodium chlorite.

5. The composition of claim 1 wherein the aqueous solution contains metal chlorite at a concentration ranging from 0.001% to 0.25% by weight.

6. The composition of claim 1 wherein the aqueous solution contains metal chlorite at a concentration ranging from 0.0025% to 0.125% by weight.

7. The composition of claim 1 wherein the protic acid is present in the aqueous solution at a concentration sufficient to lower the pH of the aqueous solution to a value from 2.0 to 4.0.

8. The composition of claim 1 wherein the protic acid is present in the aqueous solution at a concentration sufficient to lower the pH of the aqueous solution to a value from 2.5 to 3.5.

9. The composition of claim 1 wherein the aqueous solution has a chlorine dioxide concentration less than 2 ppm.

10. The composition of claim 1 wherein the aqueous solution has a chlorine dioxide concentration less than 1 ppm.

11. The composition of claim 1 wherein the aqueous solution has no detectable level of chlorine dioxide.

12. The composition of claim 1 wherein the aqueous solution is formed by mixing an aqueous solution of protic acid and an aqueous solution of metal chlorite, a protic acid in solid form and an aqueous solution of metal chlorite, an aqueous solution of protic acid and a metal chlorite in dry form, or a protic acid in dry form and a metal chlorite in dry form followed by addition of water.

13. The composition of claim 1 wherein the protic acid is an organic acid.

14. The composition of claim 13 wherein the protic acid is tartaric, citric, malic, acetic, or mixtures thereof.

15. The composition of claim 1 wherein the protic acid is an inorganic acid.

16. The composition of claim 15 wherein the inorganic acid is phosphoric acid.

17. The composition of claim 1 wherein the aqueous solution further comprises a chloride ion.

18. The composition of claim 17 wherein the chloride ion is present in the aqueous solution at a concentration ranging from 0.01% to 5%.

19. The composition of claim 17 wherein the chloride ion is present in the aqueous solution at a concentration ranging from 0.03% to 3%.

20. The composition of claim 17 wherein the source of the chloride ion is a chloride salt.

21. The composition of claim 20 wherein the chloride salt is sodium chloride or calcium chloride.

22. A method for making a frozen chlorine dioxide-containing composition, said method comprising the following steps:

1) preparing an aqueous solution comprising about 0.0005% to about 0.5% by weight of metal chlorite and a sufficient protic acid concentration to lower the pH of the aqueous solution to a value of about 1.8 to about 5.0, and wherein said prepared aqueous solution has a chlorine dioxide concentration of less than about 3 ppm at all times prior to freezing; and

2) freezing said prepared aqueous solution comprising metal chlorite and protic acid to form a frozen aqueous matrix composition wherein said formed frozen chlorine dioxide containing composition has a chlorine dioxide concentration of more than about 3 ppm.

23. The method of claim 22 wherein the metal chlorite is an alkali or alkaline earth chlorite.

24. The method of claim 22 wherein the protic acid is present in the aqueous solution at a concentration sufficient to lower the pH of the aqueous solution to a value from 2.0 to 4.0.

25. The method of claim 22 wherein the protic acid is present in the aqueous solution at a concentration sufficient to lower the pH of the aqueous solution to a value from 2.5 to 3.5.

26. The method of claim 22 wherein the aqueous solution has a chlorine dioxide concentration less than 2 ppm.

27. The method of claim 22 wherein the aqueous solution has a chlorine dioxide concentration less than 1 ppm.

28. The method of claim 22 wherein the aqueous solution has no detectable level of a chlorine dioxide.

29. The method of claim 22 wherein the aqueous solution is formed by mixing an aqueous solution of protic acid and an aqueous solution of metal chlorite, a protic acid in solid form and an aqueous solution of metal chlorite, an aqueous solution of protic acid and a metal chlorite in dry form, or a protic acid in dry form and a metal chlorite in dry form followed by addition of water.

30. The method of claim 22 wherein the metal chlorite is sodium or potassium chlorite.

31. The method of claim 30 wherein the metal chlorite is sodium chlorite.

32. The method of claim 30 wherein the aqueous solution contains metal chlorite at a concentration ranging from 0.001% to 0.25% by weight.

33. The method of claim 30 wherein the aqueous solution contains metal chlorite at a concentration ranging from 0.0025% to 0.125% by weight.

34. The method of claim 30 wherein the protic acid is an organic acid.

35. The method of claim 34 wherein the protic acid is tartaric, citric, malic, acetic, or mixtures thereof.

36. The method of claim 30 wherein the protic acid is an inorganic acid.

37. The method of claim 36 wherein the inorganic acid is phosphoric acid.

38. The composition of claim 22 wherein the aqueous solution further comprises a chloride ion.

39. The composition of claim 38 wherein the chloride ion is present in the aqueous solution at a concentration ranging from 0.03% to 3%.

40. The composition of claim 38 wherein the chloride ion is present in the aqueous solution at a concentration ranging from 0.01% to 5%.

41. The composition of claim 38 wherein the source of the chloride ion is a chloride salt.

42. The composition of claim 41 wherein the chloride salt is sodium chloride or calcium chloride.

43. The method of claim 22, further comprising the step of contacting the frozen chloride dioxide-containing composition with a chloride ion.

44. The method of claim 43 wherein the source of the chloride ion is seawater.

45. The method of claim 43 wherein the source of the chloride ion is brine.