Climate control for the transport and storage of perishables

• US 7,208,187 B2
• Filed: 03/20/2001
• Issued: 04/24/2007
• Est. Priority Date: 03/20/2000
• Status: Expired due to Fees

• Current Assignee: Gäbler, Ralph
• Original Assignee: Gäbler, Ralph
• Inventors: Gäbler, Ralph
• Primary Examiner(s): BECKER, DREW E
• Application Number:
  US10/239,224
• Publication Number:
  US 20030150334A1
• Time in Patent Office: 2,226 Days
• Field of Search: 99467-468, 994/73, 426/231, 426/312, 426/316, 426/320, 426/515, 426418-419, 73 232- 3107
• US Class Current: 426/231
• CPC Class Codes: A23B 7/152 in a controlled atmosphere comprising other gases in addition to CO2, N2, O2 or H2O ; Elimination of such other gases
• CPC Class Codes: G01N 2021/1704 in gases

Abstract

Method for the control of a controlled atmosphere for the storage of plant products in at least one storage- or transport space, where

• • a) the concentration of at least one trace gas that is produced by the plant products and has a share of less than 1% of the controlled atmosphere is measured at least twice at different times;
  • b) the degree of change in the concentration of the trace gas is derived from at least two measuring values as the measure of the production rate of the plant product for said trace gas;
  • c) the control variables for the composition in the controlled atmosphere are determined depending on the degree of change in the concentration of the trace gas, and
  • d) the composition of the controlled atmosphere is adjusted according to the control variables.

Claims

1. A method of adjusting a controlled atmosphere for the storage of plant products in at least one storage or transport space, comprising:

a) measuring a concentration of a trace gas at least twice at different times, wherein the trace gas is produced by the plant products, and wherein the trace gas represents less than 1% of the controlled atmosphere;

b) determining a production rate, wherein the production rate comprises the degree of change of the concentration of the trace gas from at least two measurements of the concentration of the trace gas taken at different times; and

c) adjusting the composition of the controlled atmosphere according to the production rate.

2. The method in accordance with claim 1, characterized in that the degree of change in the concentration of the C₂H₄-concentration is determined.

3. The method in accordance with claim 1, characterized in that the degree of change in the concentration of the C₂H₅OH-concentration is determined.

4. The method in accordance with claim 1, characterized in that the degree of change in the concentration of the C₂H₆-concentration is determined.

5. The method in accordance with claim 1, characterized in that the degree of change in the concentration of acetaldehyde is determined.

6. The method in accordance with claim 1, characterized in that the CO₂-concentration in the controlled atmosphere is not elevated artificially and the degree of change in the concentration of the CO₂-concentration is determined.

7. The method in accordance with claim 1, characterized in that the CO₂-concentration, the O₂-concentration, the room temperature and/or the air humidity are controlled.

8. The method in accordance with claim 1, characterized in that the C₂H₄-concentration in the controlled atmosphere is controlled.

9. The method in accordance with claim 1, characterized in that plant products with the same degree of ripeness are stored in spatial proximity to one another.

10. The method in accordance with claim 9, characterized in that the individual degree of ripeness of individual plant products is determined continually or intermittently or a mean degree of ripeness of parts of a load in the storage space is determined.

11. The method in accordance with claim 9, characterized in that the products are sorted according to their degree of ripeness during storage.

12. The method in accordance with claim 9, characterized in that the plant products with the same degree of ripeness are distributed to respective chambers and/or storage spaces having an atmosphere that is optimal for said plant products.

13. The method in accordance with claim 1, characterized in that a gas analysis method based on the photo-acoustic effect is used to determine the degree of change in the concentration of trace gases.

14. The method in accordance with claim 2, characterized in that the degree of change in the concentration of the C₂H₅OH-concentration is determined.

15. The method in accordance with claim 14, characterized in that the degree of change in the concentration of the C₂H₆-concentration is determined.

16. The method in accordance with claim 15, characterized in that the degree of change in the concentration of acetaldehyde is determined.

17. The method in accordance with claim 16, characterized in that a gas analysis method based on the photo-acoustic effect is used to determine the degree of change in the concentration of trace gases.

18. The method in accordance with claim 17, characterized in that plant products with the same degree of ripeness are stored in spatial proximity to one another.

19. The method of claim 1 further comprising:

a) comparing the production rate to a known pattern of changes in concentrations of one or more trace gases;

b) determining if the production rate coincides with the known pattern;

c) in response to the determining step, retrieving a set of control variables associated with the known pattern; and

d) using the control variables to adjust the composition of the controlled atmosphere.

20. A system for regulating a controlled atmosphere for plant products comprising:

a device configured to adjust the controlled atmosphere based on measuring a concentration of a trace gas at least twice at different times, wherein the trace gas is produced by the plant products, and wherein the trace gas represents less than 1% of the controlled atmosphere;

determining a production rate, wherein the production rate comprises the degree of change in concentration of the trace gas from at least two measurements of the concentration of the trace gas taken at different times; and

adjusting the composition of the controlled atmosphere according to the production rate wherein the system farther comprises a photo-acoustic sensor coupled to the device.

21. The device of claim 20 further comprising:

a) comparing the production rate to a known pattern of changes in concentrations of one or more trace gases;

b) determining if the production rate coincides with the known pattern;

c) in response to the determining step, retrieving a set of control variables associated with the known pattern; and

d) using the control variables to adjust the composition of the controlled atmosphere.