Method and apparatus for packaging respiring produce

Abstract

A method of manufacturing a modified atmosphere package is provided which comprises the steps of: providing a portion of packaging material; providing a portion of produce; forming, from the portion of packaging material and the portion of produce, a closed package defining a package volume and containing in the package volume the portion of produce and a modified atmosphere. The modified atmosphere is modified with respect to the ambient atmosphere. The method comprises providing the modified atmosphere in the package volume by providing a gas mixture of at least one atmosphere modification gas and pressurised air in the package volume. An associated apparatus is also provided.

Claims

1. A method of manufacturing a modified atmosphere package comprising steps of: providing a portion of packaging material; providing a portion of produce; providing the portion of the packaging material with one or more microperforations; forming, from the portion of packaging material and the portion of produce, a closed package defining a package volume and containing in the package volume the portion of produce and a modified atmosphere; wherein the modified atmosphere is modified with respect to ambient atmosphere; wherein the method comprises providing the modified atmosphere in the package volume by providing a gas mixture of at least one atmosphere modification gas and pressurized air in the package volume.

2. The method according to claim 1, comprising providing the pressurized air by compressing air taken from the ambient atmosphere at or near a location where the method is performed.

3. The method according to claim 1, wherein the method comprises measuring at least one of a composition, an amount and a flow rate of at least one of air to be pressurized into the pressurized air, the pressurized air and the gas mixture, prior to introducing the gas mixture into a packaging space.

4. The method according to claim 1, wherein the step of forming the package containing the portion of produce and the modified atmosphere is performed in a packaging space comprising a gas outlet, and the method comprises introducing the gas mixture into the package volume in the packaging space, and wherein the method comprises measuring at least one of a composition, an amount and a flow rate of gas at or near the gas outlet.

5. The method according to claim 1, comprising determining a respiration property of the produce to be packaged and determining on the basis of the determined respiration property of the produce to be packaged at least one of a composition of the modifying atmosphere.

6. The method according to claim 1, comprising manufacturing a series of modified atmosphere packages using the method of claim 1, wherein for each package of the series the step of forming the package containing the portion of produce and the modified atmosphere is performed in a packaging space, wherein the method comprises providing the packaging space with the gas mixture, before and/or after forming successive packages.

7. An apparatus for manufacturing a modified atmosphere package, comprising: a perforator for providing the packaging material with one or more microperforations, a device for forming, from a portion of packaging material and a portion of produce, a closable package which when closed defines a package volume and contains in the package volume the portion of produce and a modified atmosphere; a supply of pressurized air and a supply of at least one atmosphere modification gas; and a device for providing a gas mixture of the at least one atmosphere modification gas and the pressurized air in the package volume.

8. The apparatus according to claim 7, wherein the apparatus is configured to close the package.

9. The apparatus according to claim 7, wherein the apparatus comprises a gas inlet for supplying the gas mixture in or near the package, and the apparatus comprises at least one gas sensor positioned upstream of the inlet, and the gas sensor is configured to detect at least one component of the gas mixture.

10. The apparatus according to claim 9, wherein the apparatus comprises a controller operably connected with the at least one gas sensor, and the controller is operably connected with one or more regulators for controlling at least one of a composition and a flow of the gas mixture, in response to a signal from the at least one gas sensor, and/or the controller is operably connected with the device for forming a package and/or a supply of produce.

11. The apparatus according to claim 7, wherein the apparatus comprises a gas inlet for supplying the gas mixture in or near the package, at least one of a gas outlet and a produce inlet for supplying the produce to the apparatus and/or to the package, positioned downstream of the gas inlet, and at least one gas sensor positioned downstream of the inlet and upstream of, or at or near, the at least one of the gas outlet and/or the produce inlet, and the at least one gas sensor is configured to detect at least one component of the gas mixture.

12. The apparatus according to claim 7, wherein the apparatus comprises an enclosed produce supply channel having a produce filling end and a packaging end, the apparatus is configured for filling the package at or near the packaging end with produce supplied through the channel, the apparatus comprises a gas inlet into the produce supply channel for supplying the gas mixture at or near the packaging end into the produce supply channel, and the apparatus comprises at least one gas sensor upstream of the gas inlet and/or at least one gas sensor at or near the filling end, and the at least one gas sensor is configured to detect at least one component of the gas mixture.

13. The apparatus according to claim 7, wherein the apparatus comprises a produce supply channel having a produce filling end and a packaging end, and the apparatus is configured for filling the package at or near the packaging end with produce supplied through the channel, and the apparatus comprises a plurality of gas inlets into the produce supply channel for supplying the gas mixture at or near the packaging end into the produce supply channel, and/or the supply channel comprises at least partially a double wall providing a gas flow channel inside the double wall and comprising a plurality of gas inlets into the produce supply channel and/or a gas inlet having an inlet opening extending for more than about 25% of the circumference of the channel inner wall for supplying the gas mixture at or near the packaging end into the produce supply channel and/or the package.

14. The apparatus according to claim 7, wherein the apparatus comprises at least one of a controller for the perforator, a camera, and a system for determining a target package atmosphere which system may comprise a sensor and a controller.

15. A method of manufacturing a modified atmosphere package comprising steps of: providing a portion of packaging material; providing a portion of produce; forming, from the portion of packaging material and the portion of produce, a closed package defining a package volume and containing in the package volume the portion of produce and a modified atmosphere; wherein the modified atmosphere is modified with respect to the ambient atmosphere; and wherein the method comprises providing the modified atmosphere in the package volume by providing a gas mixture comprising at least one atmosphere modification gas and pressurized air in the package volume; forming the package containing the portion of produce and the modified atmosphere in a device provided with a packaging space; providing the at least one atmosphere modification gas and the pressurized air; forming the gas mixture by mixing the at least one atmosphere modification gas and the pressurize air, wherein the gas mixture has an oxygen concentration lower than 10% oxygen; and introducing the gas mixture into the packaging space.

16. The method according to claim 15, wherein the method comprises measuring at least one of a composition, an amount and a flow rate of at least one of air to be pressurized into the pressurized air, the pressurized air and the gas mixture, prior to introducing the gas mixture into a packaging space.

17. The method of claim 15, wherein, the gas mixture has an oxygen concentration between 10% and 0.5% oxygen.

18. An apparatus for manufacturing a modified atmosphere package, comprising: a device for forming, from a portion of packaging material and a portion of produce, a closable package which when closed defines a package volume and contains in the package volume the portion of produce and a modified atmosphere; and a device for providing the modified atmosphere by providing a gas mixture comprising at least one atmosphere modification gas and pressurized air in the package volume; a supply of the pressurized air and a supply of the at least one atmosphere modification gas; a device for forming the gas mixture by mixing the at least one atmosphere modification gas and the pressurized air to an oxygen concentration of the gas mixture lower than 10% oxygen, and a device for providing the gas mixture of the at least one atmosphere modification gas and the pressurized air in the package volume.

19. The apparatus according to claim 18, wherein the apparatus comprises a gas inlet for supplying the gas mixture in or near the package, and at least one gas sensor positioned upstream of the inlet configured to measure at least one of a composition, an amount and a flow rate of at least one of air to be pressurized into the pressurized air, the pressurized air and the gas mixture, prior to introducing the gas mixture into the packaging space.

20. The apparatus according to claim 18, wherein the device for forming the gas mixture by mixing the at least one atmosphere modification gas and the pressurized air is configured for mixing the gas mixture to an oxygen concentration of the gas mixture between 10% and 0.5% oxygen.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above-described aspects will hereafter be more explained with further details and benefits with reference to the drawings showing a number of embodiments by way of example.

(2) FIG. 1 schematically shows an embodiment of an apparatus and indicates at least part of an embodiment of a method;

(3) FIG. 2 schematically shows a gas mixing system;

(4) FIG. 3 schematically shows, in cross section, a package forming device of an embodiment of an apparatus and indicates at least part of an embodiment of a method.

DETAILED DESCRIPTION OF EMBODIMENTS

(5) It is noted that the drawings are schematic, not necessarily to scale and that details that are not required for understanding the present invention may have been omitted. The terms “upward”, “downward”, “below”, “above”, and the like relate to the embodiments as oriented in the drawings, unless otherwise specified. Further, elements that are at least substantially identical or that perform an at least substantially identical function are denoted by the same numeral, where helpful individualised with alphabetic suffixes.

(6) FIG. 1. shows schematically an apparatus 1 for manufacturing modified atmosphere packages 3. The apparatus 1 comprises a package forming device 5 for forming, from portions of packaging material 7 and portions of produce 9, modified atmosphere packages 3 each defining a package volume V and containing in the package volume V a portion of produce 9 and a modified atmosphere. Here, the packaging material is supplied as a web of a packaging film 11 on a roll 13 for forming bags but other forms and types of packaging material are also possible; e.g. two or more types of packaging material may be provided, such as trays and sealing film (not shown). In FIG. 1 the produce is provided as separate portions 9 by a produce transporter 14, but other ways of providing the produce as, or into, portions 9 may be used. Here, the apparatus 1 is configured to form and fill the packages 3 and also to close and separate them.

(7) The apparatus 1 comprises a supply 15 of pressurised air, here in the form of a compressor 17 provided with filters 19, and supplies 21, 23 of different atmosphere modification gases, e.g. CO.sub.2 and N.sub.2, here in the form of gas bottles. The compressor is provided with a buffer tank 24.

(8) Filtering of the pressurised air may comprise plural filtering steps, and may comprise reducing at least one of dust, liquids, gases from the ambient air. Suitable filters may comprise particle filters, (activated) carbon filters, gas scrubbers, dryers, etc.

(9) Preferably, the atmosphere modification gas(es) is (are) also supplied pressurised so that both the pressurised air and the atmosphere modification gas(es) are at elevated pressure relative to the ambient atmosphere and may be transported by flowing under their own pressure so that one or more propellers are not needed; however, these may be provided.

(10) The pressurised air may have a pressure of below 5 bar, e.g. below 2 bar such as 0.5 to 1.5 bar overpressure (1 bar=100 kPa). The atmosphere modification gas may have a similar pressure; if gas supplies are used with high filling pressures of up to about 200 bar overpressure, as usual, a reduction valve should preferably be used.

(11) The apparatus 1 comprises a device 25 for providing a gas mixture of one or more of the atmosphere modification gas from the supplies 21, 23 and the pressurised air from the supply 15 in the package volume V of each package 3 as that is formed. Here, the device 25 comprises a manifold 27 connected by a gas supply conduit 31 to the package forming device 5. The manifold 27 and an optional feedback sensor signal line 33 are connected to a controller 29.

(12) Also referring to FIG. 2, a suitable manifold 27 may comprise for one or each of the (supplies 21, 23 of) atmosphere modification gases and/or for the (supply 15 of) pressurised air, a regulator 271, e.g. a pressure regulator and/or a flow controller, possibly combined with a filter 272, a controller-operable valve 273 and/or a hand-operable valve 274. The manifold serves for combining the atmosphere modification gases and the pressurised air as a gas mixture into the gas supply conduit 31, which may also be provided with a controller-operable and/or a hand-operable valve 275. Further, a gas composition sensor 276 may be provided. Additionally, one or more buffer tanks 277, 278 for pressurised air and/or the gas mixture may be provided, also with controller and/or hand operable valves 279.

(13) As indicated in FIG. 1, the apparatus 1 further comprises a perforator, here a (possibly pulsed) laser 35 providing a (pulsed) laser beam 36, and a camera 37 for imaging microperforations and/or other control processes. The laser 35 and the camera 37 are operably connected with a perforation controller 39 for operational control, quality control and/or feedback control of the laser 35. The controller 39 may be programmable for determining one or more of the number, size and positions of the microperforations.

(14) Further, not shown in any detail, the apparatus 1 may comprise a detector 41 and a calculator 43 configured to determine, e.g. by measuring and calculating on the basis of measurement results, one or more respiration properties, e.g. an O.sub.2 consumption and/or CO.sub.2-production of the produce to be packaged and, based on that/those, determining one or more of a composition of the target modified atmosphere, a composition of the modifying atmosphere, a number and/or size of one or more microperforations (to be) made in the packaging material of the package(s).

(15) Two or more of the gas mixture controller 29, the perforation controller 39, the detector 41 and the calculator 43 may be interconnected (e.g. see dashed lines) and/or integrated in one combined controller.

(16) FIG. 3 schematically shows, in cross section, a package forming device 5A for an apparatus in accordance with the principles set out herein, e.g. as indicated in FIG. 1. The device 5A comprises an enclosed produce supply channel 501, extending in an axial direction A, here a pipe in the form of a vertical chute for the produce from a hopper 502. The channel 501 has a produce filling end 503 and a packaging end 505. Optionally, the hopper 502 is closable, e.g. by one or more covers 506, to function as a lock for reduction of gas loss. The channel 501 and the hopper 502 or other produce supply may be integrated or separate and any spaces in between may be closed against gas leaks or rather have one or more gas outlets. The package forming device 5A is configured to fill packages 3 at or near the packaging end 505 with a portion of produce 9 supplied through the chute. The package 3 may also be formed around the channel 501 from a (microperforated) sheet of the packaging material, e.g. by welds or seals such as seal 4.

(17) The shown channel 501 is double walled, having an outer wall 507 and an inner wall 509 providing a gas flow channel 511 in between and around the circumference channel, connected to a gas supply conduit 531 for supplying a gas mixture, in particular a gas mixture comprising an atmosphere modification gas and pressurised air, to the channel (FIG. 3, thin arrows). In FIG. 3, the inner wall 509 of the channel ends within the outer wall 507, above the bottom end of the latter (by an offset H). Thus, the channel 501 has a gas inlet 513 into the package 3 to be filled and the channel 501 extending substantially around the circumference of the channel inner wall 509 for supplying the gas mixture at or near the packaging end 505 into the produce supply channel and/or the package 3 (FIG. 3, thin arrows). The offset H facilitates definition of the end of the channel 501 and directing the gas into the channel 501. The bottom end of the outer wall 507 may be provided with an inward protrusion 507A for directing a gas flow.

(18) The channel 501 is provided with a first gas sensor 515 upstream of the gas inlet 513, a second gas sensor 517 near the packaging end 505 close to the gas inlet 513, and a third gas sensor 519 near the filling end 503 both sensors 517 and 519 are arranged on an inside of the channel 501 and downstream of the gas inlet 513. Each of the gas sensors 515, 517, 519 is connected to a gas composition detector and controller, possibly integrated (cf. controller 25 of FIG. 1).

(19) In use for manufacturing a modified atmosphere package, an unfilled package 3 is provided at the packaging end 505 of the channel 501, here surrounding it, and a gas mixture is supplied to the channel 501 and the package 3 through the gas inlet 513 (FIG. 3, thin arrows). Thus, the atmosphere at and near the packaging end 505 and in the package 3 is modified relative to the initial, un-modified ambient atmosphere. Establishment of a sufficiently modified atmosphere can be determined by detection of predetermined (not necessarily identical) gas compositions with the second and third sensors 517 and 519. Then a portion of produce 9 is provided into the channel 501 from the filling end 503 and filled into the package 3 (FIG. 3, bold arrow and shape 9). The portion 9 may be supplied in one instant or in a series of partial portions. Thereafter the filled package 3 may be closed. Thus a closed modified atmosphere package 3 is formed defining a package volume V and containing in the package volume V the portion of produce 9 and modified atmosphere containing a gas mixture of at least one atmosphere modification gas and pressurised air in the package volume V.

(20) The method can thereafter be repeated with a subsequent package and portion of produce 9. If filling of the subsequent package is slowed for some reason, gas introduction may be reduced and after some time stopped or restarted at or before restarting of the filling process, based on detection data from the sensors 515, 517, 519.

(21) The disclosure is not restricted to the above described embodiments which can be varied in a number of ways within the scope of the claims. For instance, the package may be provided with an overpressure relative to the ambient atmosphere. Packages may be supported on a transporter during filling. Packages may be closed by hand. Gas composition sensors may be placed differently and/or be formed as an optical detector. Weighing devices may be added. A (micro)perforator may be absent. The apparatus and/or method may be provided as/performed on new apparatus but are also possible as a retrofit. A chute-based packaging machine need not be double walled but may have one or more gas and/or air filling ducts. The sensor 515 or a further gas sensor may be located in a buffer tank 278.

(22) A packaging space of a tray sealing device may be defined by openable and closable covers.

(23) Elements and aspects discussed for or in relation with a particular embodiment may be suitably combined with elements and aspects of other embodiments, unless explicitly stated otherwise.