Sensor for high pressure processing of articles

• US 8,640,546 B2
• Filed: 09/12/2011
• Issued: 02/04/2014
• Est. Priority Date: 09/12/2011
• Status: Active Grant

• Current Assignee: Del Monte Limited (Fresh Del Monte Produce Incorporated)
• Original Assignee: Del Monte Corporation (Conagra Brands, Inc.)
• Inventors: Trahan, Caitlin Elizabeth, Shimek, Justin Wade, Lem, Russell Allan, Hart, Andrew Richard
• Primary Examiner(s): Caputo, Lisa
• Assistant Examiner(s): JENKINS, JERMAINE L
• Application Number:
  US13/230,382
• Publication Number:
  US 20130061681A1
• Time in Patent Office: 876 Days
• Field of Search: None
• US Class Current: 73/700
• CPC Class Codes: A23L 3/00 Preservation of foods or foodstuffs, in general, e.g. pasteurising, sterilising, specially adapted for foods or foodstuffs preserving foods or foodstuffs in association with packaging B65B55/00
• CPC Class Codes: A23L 3/003 Control or safety devices for sterilisation or pasteurisation systems
• CPC Class Codes: A23L 3/0155 using sub- or super-atmospheric pressures, or pressure variations transmitted by a liquid or gas
• CPC Class Codes: A61L 2/28 Devices for testing the effectiveness or completeness of sterilisation, e.g. indicators which change colour apparatus involving enzymes or microorganisms C12M1/34; methods involving enzymes or microorganisms C12Q1/00
• CPC Class Codes: B01J 13/00 Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
• CPC Class Codes: C09B 67/0097 Dye preparations of special physical nature; Tablets, films, extrusion, microcapsules, sheets, pads, bags with dyes
• CPC Class Codes: G01L 7/00 Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements G01L11/004 takes precedence; transmitting or indicating the displacement of mechanical pressure-sensitive elements by electric , e.g., photoelectric or magnetic means G01L9/00; measuring differences of two or more pressure values G01L13/00; measuring two or more pressure values simultaneously G01L15/00
• CPC Class Codes: G01L 7/187 with optical transmitting or indicating means

Abstract

A pressure sensor device and its use for confirming achievement of a selected pressure in a high pressure process (HPP) for sanitizing food is disclosed. The device includes at least a base and a sheet, each of which is substantially impermeable to the working fluid of the HPP and is deformable at the selected pressure. Microcapsules interposed between flat overlapping portions of the base and sheet contain a color former and burst upon pressurization of the environment surrounding the device. Release of the color former is detected to confirm that the pressurization occurred. The device can be associated with one or more foodstuffs (e.g., a packaged food product or a group of such packages) and remain associated therewith to continuously indicate that the foodstuff(s) have been subjected to the selected pressure and are therefore sanitized.

Claims

1. An assembly for indicating achievement of a selected ambient pressure in a high pressure process for treating a foodstuff using a working fluid, the assembly comprising the foodstuff reliably associated with a pressure sensor device that comprises a base, a sheet, and a plurality of microcapsules,

each of the base and the sheet being substantially impermeable to the working fluid, being deformable at the selected ambient pressure, and bearing a substantially flat portion;

the substantially flat portions of the base and sheet being disposed in a substantially parallel, opposed conformation defining an overlapping region having lateral dimensions and an average separation distance,

the plurality of microcapsules being interposed between the base and the sheet in the overlapping region;

the microcapsules containing a color former and having a compressive bursting strength less than the selected ambient pressure; and

at least one of the base and the sheet having a viewing portion adapted to permit detection of color former released from the microcapsules by external visual observation of the device,

whereby when the assembly is subjected to the selected ambient pressure, at least some microcapsules in the overlapping region burst, the color former is released from the microcapsules, and release of the color former can be detected by external visual observation of the device.

2. The assembly of claim 1, wherein at least a fraction of the microcapsules are disposed within a portion of the overlapping region that contains a compressible fluid.

3. The assembly of claim 2, wherein the fluid is air.

4. The assembly of claim 1, wherein the base has the form of a second sheet.

5. The assembly of claim 4, wherein each of the base and the sheet is a polyester film having a thickness of about 2 to 10 mils and at least one of the base and the sheet is transparent.

6. The assembly of claim 1, wherein the microcapsules are bound to the base.

7. The assembly of claim 1, wherein the microcapsules are bound to the sheet.

8. The assembly of claim 1, wherein the compressive bursting strength of the microcapsules is not more than 200 megaPascals (MPa).

9. The assembly of claim 1, wherein one of the base and the sheet bears the microcapsules and the other bears a color developer that reacts with the color former to generate a colored product.

10. The assembly of claim 1, wherein one of the base and the sheet bears the microcapsules and the other is transparent and bears an absorbent material for absorbing the color former when it is released from the microcapsules.

11. The assembly of claim 1, wherein the average separation distance is at least 100 times smaller than the minimum lateral dimension of the overlapping region.

12. The assembly of claim 1, wherein the device is reliably associated with a plurality of foodstuffs.

13. The assembly of claim 12, wherein the device is reliably associated with a rack that holds the plurality of foodstuffs.

14. The assembly of claim 13, wherein the foodstuffs cannot be removed from the rack without displacing the device from the rack.

15. The assembly of claim 1, wherein the device is reliably associated with a package that contains the foodstuff.

16. The assembly of claim 15, wherein the package is selected from the group consisting of a flexible bottle and a flexible pouch.

17. The assembly of claim 1, wherein the device is sealed within a sheath that is substantially impermeable to the working fluid.

18. The assembly of claim 17, wherein the sheath is substantially evacuated.

19. A method of confirming achievement of a selected ambient pressure in a high pressure process for treating a foodstuff using a working fluid, the method comprising reliably associating the foodstuff with a pressure sensor device that comprises a base, a sheet, and a plurality of microcapsules,

each of the base and the sheet being substantially impermeable to the working fluid, being deformable at the selected ambient pressure, and bearing a substantially flat portion;

the substantially flat portions of the base and sheet being disposed in a substantially parallel, opposed conformation relative to one another to define an overlapping region having lateral dimensions and an average separation distance,

the plurality of microcapsules being interposed between the base and the sheet in the overlapping region;

the microcapsules containing a color former and having a compressive bursting strength less than the selected ambient pressure; and

at least one of the base and the sheet having a viewing portion adapted to permit detection of color former released from the microcapsules by external visual observation of the device,

subjecting the foodstuff to the process, and

visually observing the viewing portion of the device, whereby visual detection of color former at the viewing portion confirms that the selected ambient pressure was achieved.

20. The method of claim 19, wherein at least a fraction of the microcapsules are disposed within a portion of the overlapping region that contains a compressible fluid.

21. The method of claim 20, wherein the fluid is air.

22. The method of claim 19, wherein the base has the form of a second sheet.

23. The method of claim 22, wherein each of the base and the sheet is a polyester film having a thickness of about 2 to 10 mils and at least one of the base and the sheet is transparent.

24. The method of claim 19, wherein the microcapsules are bound to the base.

25. The method of claim 19, wherein the microcapsules are bound to the sheet.

26. The method of claim 19, wherein the compressive bursting strength of the microcapsules is not more than 200 megaPascals (MPa).

27. The method of claim 19, wherein one of the base and the sheet bears the microcapsules and the other bears a color developer that reacts with the color former to generate a colored product.

28. The method of claim 19, wherein one of the base and the sheet bears the microcapsules and the other is transparent and bears an absorbent material for absorbing the color former when it is released from the microcapsules.

29. The method of claim 19, wherein the average separation distance is at least 100 times smaller than the minimum lateral dimension of the overlapping region.

30. The method of claim 19, wherein the device is reliably associated with a plurality of foodstuffs.

31. The method of claim 30, wherein the device is reliably associated with a rack that holds the plurality of foodstuffs,

32. The method of claim 31, wherein the foodstuffs cannot be removed from the rack without displacing the device from the rack.

33. The method of claim 19, wherein the device is reliably associated with a package that contains the foodstuff.

34. The method of claim 33, wherein the package is selected from the group consisting of a flexible bottle and a flexible pouch.

35. The method of claim 19, wherein the device is sealed within a sheath that is substantially impermeable to the working fluid.

36. The method of claim 35, wherein the sheath is substantially evacuated.

37. In a high pressure process for treating a foodstuff using a working fluid, the improvement comprising reliably associating the foodstuff with a pressure sensor device that comprises a base, a sheet, and a plurality of microcapsules,

each of the base and the sheet being substantially impermeable to the working fluid, being deformable at the selected ambient pressure, and bearing a substantially flat portion;

the substantially flat portions of the base and sheet being disposed in a substantially parallel, opposed conformation relative to one another to define an overlapping region having lateral dimensions and an average separation distance,

the plurality of microcapsules being interposed between the base and the sheet in the overlapping region;

the microcapsules containing a color former and having a compressive bursting strength less than the selected ambient pressure; and

at least one of the base and the sheet having a viewing portion adapted to permit detection of color former released from the microcapsules by external visual observation of the device, and

visually observing the viewing portion of the device after subjecting the foodstuff to the process, whereby visual detection of color former at the viewing portion confirms that the selected ambient pressure was achieved.

38. The improvement of claim 37, wherein at least a fraction of the microcapsules are disposed within a portion of the overlapping region that contains a compressible fluid.

39. The improvement of claim 38, wherein the fluid is air.

40. The improvement of claim 37, wherein the base has the form of a second sheet.

41. The improvement of claim 40, wherein each of the base and the sheet is a polyester film having a thickness of about 2 to 10 mils and at least one of the base and the sheet is transparent.

42. The improvement of claim 37, wherein the microcapsules are bound to the base.

43. The improvement of claim 37, wherein the microcapsules are bound to the sheet.

44. The improvement of claim 37, wherein the compressive bursting strength of the microcapsules is not more than 200 megaPascals (MPa).

45. The improvement of claim 37, wherein one of the base and the sheet bears the microcapsules and the other bears a color developer that reacts with the color former to generate a colored product.

46. The improvement of claim 37, wherein one of the base and the sheet bears the microcapsules and the other is transparent and bears an absorbent material for absorbing the color former when it is released from the microcapsules.

47. The improvement of claim 37, wherein the average separation distance is at least 100 times smaller than the minimum lateral dimension of the overlapping region.

48. The improvement of claim 37, wherein the device is reliably associated with a plurality of foodstuffs.

49. The improvement of claim 48, wherein the device is reliably associated with a rack that holds the plurality of foodstuffs,

50. The improvement of claim 49, wherein the foodstuffs cannot be removed from the rack without displacing the device from the rack.

51. The improvement of claim 37, wherein the device is reliably associated with a package that contains the foodstuff.

52. The improvement of claim 51, wherein the package is selected from the group consisting of a flexible bottle and a flexible pouch.

53. The improvement of claim 37, wherein the device is sealed within a sheath that is substantially impermeable to the working fluid.

54. The improvement of claim 53, wherein the sheath is substantially evacuated.