Device and method for introducing carbon dioxide into fresh meat

Abstract

A device for introducing cold carbon dioxide into fresh meat has at least one injection needle which is mounted on a housing and is in the form of a hollow needle and by means of which liquid carbon dioxide is introduced into a piece of meat from a supply line. After the injection process, the device is removed from the piece of meat, and the carbon dioxide expands in the piece of meat while forming carbon dioxide gas and carbon dioxide snow. The carbon dioxide gas supplied and produced by sublimating the carbon dioxide snow diffuses into the surrounding tissue and there ensures a uniform cooling of the treated piece of meat before gradually reaching the outside through openings in the tissue.

Description

[0001] Device and method for introducing carbon dioxide into fresh meat

[0002] The invention relates to a device for introducing carbon dioxide snow into fresh meat. The invention further relates to a method for introducing carbon dioxide snow into fresh meat using a corresponding device.

[0003] The biochemical processes as well as the structural changes post-mortem in the meat of various slaughtered animals and the associated changes in meat quality are described, for example, in the article by R. Binke: “From Muscle to Meat”, BAFF Bulletin 42, No. 162, p. 347 (2003).

[0004] Due to the accumulation of the metabolic product lactate (a salt of lactic acid), the muscle pH drops from pH 6.8 to 7.2 to pH 5.5 within a few hours. This process is also known as acidification. The speed of this process and the final pH value are of great importance for the maturation process and storage life, and thus for the quality of the meat. Since these processes are temperature-dependent, the cooling process after slaughter also has a decisive influence on meat quality.

[0005] High temperatures in meat lead to rapid biochemical reactions, which can lead to a rapid reduction in pH to values ​​below 5.6 and, consequently, to the development of undesirable "PSE meat." On the other hand, too rapid cooling of the carcass to temperatures below 10°C before rigor mortis sets in is also detrimental, as it inhibits the acidification of the meat necessary for good meat quality and causes cold shortening in the muscle. The resulting "DFD meat" (in pork) or "DCB meat" (in beef) is characterized by a high pH of over 6.2; it is tough and has low juice retention capacity.

[0006] Furthermore, especially with larger cuts of meat, it is important that cooling occurs evenly throughout the meat volume, as uneven cooling rates lead to uneven maturation and thus uneven meat quality within the cut. In the processing of ham, for example, this often results in the meat located deep within the meat, closest to the bone, being removed as inferior and excluded from further processing.

[0007] "Fresh meat" refers to meat during the processing period between slaughter and the completion of the meat maturation process. Meat maturation involves a series of biochemical reactions that take place in the muscle meat after slaughter. Various enzymes inherent in the meat promote these processes, thus enhancing the edibility of the meat. The maturation process must take place under controlled conditions, particularly at a controlled temperature and pH.

[0008] EP 0 707 796 A1 and US 5413 526 B1 disclose apparatuses in which a solid coolant, in particular dry ice, can be injected into a piece of meat. Each apparatus comprises a slitting means used to create a pocket in the piece of meat to be cooled, which is then filled with a dry ice block or a plurality of smaller dry ice pellets made of solid carbon dioxide by means of a feed device. The gradually sublimating dry ice ensures thorough cooling of the meat tissue. A disadvantage of this is that the introduction of a comparatively large quantity of coolant into individual large pockets results in very inhomogeneous cooling, which in turn leads to inhomogeneous meat quality. Furthermore, the dry ice particles cannot always be securely held in the cut pockets, resulting in additional labor and loss of coolant.

[0009] The subject matter of EP 4 048 077 A1 comprises an arrangement with multiple injection lances, by means of which a plurality of dry ice pellets can be introduced simultaneously into a piece of meat at a distance from one another. This supplies a comparatively large volume with dry ice pellets, and localized overcooling in the meat is avoided. A disadvantage of these known devices, however, is that the injection of dry ice pellets into meat requires a high level of equipment complexity, and in particular, loading the equipment with the pellets is subject to a certain degree of susceptibility to failure. The invention is therefore based on the object of creating a device for cooling fresh meat using carbon dioxide, which overcomes the disadvantages of the prior art and enables rapid and efficient cooling of the meat.

[0010] This object is achieved by a device having the features of patent claim 1 and by a method having the features of patent claim 7. Advantageous embodiments of the invention are specified in the subclaims.

[0011] According to the invention, a device for introducing carbon dioxide snow into fresh meat is equipped with a housing and at least one injection needle arranged on the housing and intended for insertion into a piece of meat, through the longitudinal extent of which an injection channel is guided, which opens out at least one outlet opening in the region of a distal end of the injection needle and is fluidly connected at its inlet opening opposite the distal end of the injection needle to a supply line connected to a source of liquid carbon dioxide.

[0012] The injection needle(s) is / are, for example, a hollow needle constructed like a cannula, the length of which is, for example, between 5 cm and 50 cm, preferably between 5 cm and 20 cm, and the outer diameter of which is, for example, between 3 mm and 15 mm, preferably between 4 mm and 10 mm. The at least one injection needle, like the supply line, is intended and suitable for supplying liquid carbon dioxide and, for this purpose, is designed to be particularly pressure-resistant. It is tubular in design, thus having only one injection channel inside, which extends through almost the entire length of the injection needle up to the tip region.In a first embodiment, the injection channel can exit directly at the distal end of the injection needle; however, to prevent the injection channel from becoming blocked by penetrating flesh tissue during use, a preferred embodiment is one in which the tip at the distal end of the injection needle is closed, while the injection channel branches in the region of the distal end of the injection needle and exits laterally at one or more radially spaced-apart outlet openings toward the tip of the injection needle. For example, the injection channel branches in a T- or Y-shape in the region of the distal end of the injection needle and exits laterally at two opposite outlet openings toward the tip of the injection needle.

[0013] The housing is preferably equipped with a handle (in the case of manual operation) or with connecting means for attaching a driving machine to drive the injection needles into a piece of meat to be treated.

[0014] The supply line for liquid carbon dioxide is expediently equipped with a valve, which in turn is data-linked to a control unit, preferably an electronic one, which regulates the supply of carbon dioxide to the piece of meat according to a predefined program depending on certain parameters, such as the type of meat or the respective cooling task. However, manual actuation of the valve is also conceivable within the scope of the invention, which can be used in addition to or instead of the automatic actuation.

[0015] In order to increase the cooling volume in the piece of meat to be treated, an advantageous embodiment of the invention provides that several injection needles, for example two, three, four or more injection needles, are arranged at a distance from one another on the housing of the device.

[0016] In order to prevent the needles from slipping sideways when being pushed into the piece of meat, an advantageous embodiment of the invention provides that the one injection needle or the plurality of injection needles is / are firmly accommodated in a front plate of the housing, which is preferably rigid and made of metal, for example. In particular, when a plurality of injection needles are arranged on the housing, the rigid front plate stabilizes the arrangement when being driven into the piece of meat. This makes handling of the device easier. For example, the injection needle or a plurality of injection needles is firmly but detachably connected to the front plate via screw connections, for example screwed into corresponding threaded holes in the front plate or passed through holes in the plate and fastened with nuts on both sides.The flow connection to the supply line for liquid carbon dioxide preferably extends through the front plate, for example, by the injection needles being passed through the front plate as a whole or by the injection channel being fluidly connected to the supply line at its rear end opposite the distal end of the injection needle via a channel passed through the front plate. If the device has a plurality of injection needles, the injection channels are preferably fluidly connected to the supply line for liquid carbon dioxide via a gas distributor. The gas distributor is preferably arranged in the housing of the device or within the front plate. In this case, too, the flow connections from the injection needles to the gas distributor preferably run through the front plate in the manner described above.

[0017] Preferably, the supply line for liquid carbon dioxide is equipped with a phase separator for separating gaseous carbon dioxide from the liquid carbon dioxide, which can be arranged outside or inside the housing. The phase separator ensures that exclusively, or almost exclusively, liquid carbon dioxide enters the injection channel of the at least one injection needle and from there into the piece of meat. This allows for a precise determination of the amount of carbon dioxide introduced by the injection.

[0018] The object of the invention is also achieved by a method having the features of patent claim 7.

[0019] A method according to the invention for introducing carbon dioxide snow into fresh meat using a device according to the invention is characterized in that at least one injection needle equipped with an injection channel is introduced into a piece of meat, then liquid, pressurized carbon dioxide from the feed line for liquid carbon dioxide is introduced via the injection channel into the piece of meat, in which it expands with strong cooling to produce a mixture of carbon dioxide snow and carbon dioxide gas, and then the injection needle is withdrawn from the piece of meat, wherein the injected carbon dioxide remains in the piece of meat after the injection needle has been withdrawn, and finally the injected orCarbon dioxide gas produced by sublimation of the carbon dioxide snow escapes into the environment via channels and openings in the flesh tissue, for example via the stick channel left by the injection needle or needles.

[0020] To treat a piece of meat, for example a ham, the device according to the invention is placed in front of the piece of meat to be treated in such a way that the injection needle with its distal end or the injection needles with their distal ends are directed towards the piece of meat. The injection needle(s) is / are then inserted into the piece of meat until at least the outlet opening(s) of the injection channel(s) is / are completely enclosed by the tissue of the piece of meat. The injection needle(s) are driven into the piece of meat either manually or by means of a drive unit which is, for example, pneumatically or electrically driven and moves the device together with its housing in such a way that the injection needle(s) is / are pushed into the piece of meat. As soon as the injection needle(s) are in their working position in the piece of meat, i.e.For example, by inserting the distal end of the device over a predetermined distance of, for example, 3 cm to 10 cm within the piece of meat, liquid carbon dioxide from the carbon dioxide source is injected into the piece of meat via the injection channel(s) at a pressure of, for example, 8 bar to 20 bar for a period of, for example, 0.2 s to 3 s. In particular, if multiple injection needles are attached to the device, the injection time can be shortened, to, for example, between 0.1 s and 0.5 s. The device is then withdrawn from the piece of meat and is ready for the next injection.

[0021] The liquid carbon dioxide injected into the piece of meat expands as it exits the respective injection channel and, under strong cooling, partially converts into carbon dioxide snow and partially into carbon dioxide gas. The rapidly expanding carbon dioxide gas leads to the formation of temporary cavities in the meat tissue, filled with carbon dioxide gas and partially with carbon dioxide snow. These cavities initially remain even after the injection needle is withdrawn from the piece of meat, with the gradually sublimating carbon dioxide snow providing a certain supply of cold gas. In this way, the treated region of the piece of meat is intensively cooled. Over time, the injected carbon dioxide escapes through channels and openings in the meat tissue, in particular through the puncture channel left by the injection needle.Surprisingly, it has been found that the formation of such gas cavities in meat tissue neither leads to destruction of the tissue structure nor reduces the quality of the meat. On the contrary, it facilitates the separation of different tissue parts, for example, the separation of muscle meat from bone.

[0022] By adjusting the length of time for which liquid carbon dioxide is injected into the piece of meat, the amount of carbon dioxide snow produced can be tailored to specific requirements. When cooling fresh meat using carbon dioxide snow, it is particularly important to avoid freezer burn. Therefore, the duration of an injection, i.e. the period during which liquid carbon dioxide is supplied, should be between 0.1 s and 3 s, whereby the expansion of the liquid carbon dioxide in the piece of meat produces an amount of, for example, 0.5 g to 100 g of carbon dioxide snow per injection needle. The optimal injection duration depends on the type and size of the piece of meat to be treated. It is determined empirically, for example, through tests before the start of regular use of the device.Information about suitable injection durations can also be stored in a work program of the control unit.

[0023] The device and method according to the invention are suitable for cooling various types of meat, in particular beef and pork. A particularly preferred application is the treatment of ham (pork leg or shoulder), where they enable uniform cooling in the area surrounding the bone, particularly in the region of a bone. They are particularly suitable for the treatment of fresh meat immediately after slaughter. The invention makes it possible to achieve a rapid cooling rate across the entire volume of meat, particularly in a large, undivided or non-boned piece of meat, thereby achieving a consistently high meat quality. For example, uniform cooling across the entire volume of the piece of meat by a temperature difference of 25 to 40°C can be achieved within a period of 30 to 120 minutes.

[0024] An embodiment of the invention will be explained in more detail with reference to the drawing. The sole drawing (Fig. 1) schematically shows a device according to the invention.

[0025] The device 1 shown in Fig. 1, designed as a handheld device, has a housing 2 with a handle 3 - here only indicated by a dash-dotted line. The housing 2 has a fixed front plate 4, made of metal, for example, in which a plurality of injection needles 5, 6, two in the exemplary embodiment, are firmly but detachably fastened, for example by screwing into a thread. The injection needles 5, 6, which each have an outer diameter of between 4 mm and 15 mm and a length of between 50 mm and 300 mm, are essentially tubular (cylindrical) and each have an injection channel 7, 8 inside, which runs through almost the entire longitudinal extent of the injection needle 5 or 6.Each of the channels 7, 8 branches off in the region of a tapered distal end 9, 10 of the respective injection needle 5, 6 and opens into a plurality of outlet channels 11a, 11b; 12a, 12b laterally from the distal end 9, 10 of the respective injection needle 5, 6. In the exemplary embodiment, these are two outlet channels 11a, 11b; 12a, 12b each, which adjoin the respective injection channel 7, 8 in a Y-shape. However, other geometries are also possible, such as a T-shape in which the outlet channels run perpendicular to the longitudinal axis of the injection channel, and / or a larger number of outlet channels that exit laterally on the injection needle, for example, at equal angular intervals.

[0026] The injection channels 7, 8 are accessible via holes 13, 14 in the front plate 4 of the

[0027] Housing 2 is fluidically connected to a gas distributor 15, which is arranged in the housing 2, on the side of the front panel 4 opposite the injection needles 5, 6, or (not shown here) is integrated in the front panel 4. The gas distributor 15 is fluidically connected to a supply line 16 for liquid carbon dioxide. The pressure-resistant supply line 16, which is designed at least in sections as a flexible hose line, is connected in a manner not shown here to a source for liquid carbon dioxide, which is, for example, a tank in which carbon dioxide is stored at ambient temperature and a pressure of, for example, between 12 bar and 20 bar. A valve 17, for example an electromagnetic valve, is arranged in the supply line 16 for closing and opening the supply line 16.In the supply line 16, outside the housing 2, a gas phase separator (not shown here) is arranged, by means of which the carbon dioxide gas contained in the liquid carbon dioxide can be separated.

[0028] The valve 17 is in data communication with an electronic control unit 19, by means of which the valve 17 can be controlled according to a predetermined program. An operating panel 20, which is also data-connected to the control unit 19 and is arranged, for example, on the surface of the housing 2, furthermore enables the manual input of data and / or control commands by an operator. Furthermore, detector means 21, for example a photo-optical sensor, can be provided, by means of which a positioning of a piece of meat 22 to be treated relative to the device 1 suitable for the injection of carbon dioxide can be determined. The detector means 21 and, if appropriate, further electronic elements not shown here are also in data communication with the control unit 19. The control unit 19 can be arranged within the housing 2 or, as shown here, remotely therefrom.For this purpose, the control unit 19 is connected to the electronic elements 17, 20, 21 via a data line 23 or via wireless data transmission. Not shown here, but nevertheless present, is a power supply for the electronic elements 17, 20, 21, for example, via a power line or a battery supply arranged in the housing 2.

[0029] When the device 1 is used, it is positioned with the distal ends 9, 10 of the injection needles 5, 6 on a surface 25 of the piece of meat 22 to be treated, which is, for example, a ham, wherein, if necessary, the detector means 21 determine a suitable location for positioning the injection needles 5, 6 on the piece of meat 22. The valve 17 is initially closed. Subsequently, the injection needles 5, 6 are driven so deeply into the piece of meat 22 that the distal ends 9, 10 of the injection needles 5, 6 are each located approximately 5 cm to 10 cm below the surface 25 of the piece of meat 22; at least, however, so deep that the outlet channels 11a, 11b; 12a, 12b are completely enclosed by the tissue of the piece of meat 22 at their outlets from the injection needles 5, 6 (“working position” of the injection needles 5, 6).

[0030] Subsequently, valve 17 is opened, again by manually entered control command or program-controlled. This causes liquid carbon dioxide to flow at a pressure of, for example, 12 bar through the supply line 16 and the injection channels 7, 8. Any gas phase contained in the supplied liquid carbon dioxide stream is removed by the upstream gas phase separator. The liquid carbon dioxide enters the piece of meat 22 via the outlet channels 11a, 11b; 12a, 12b and expands there, undergoing significant cooling, transforming into a mixture of carbon dioxide gas and carbon dioxide snow. The carbon dioxide snow rapidly sublimates to carbon dioxide gas in the warm tissue.

[0031] After a predetermined period of time, for example, 0.1 s to 3 s, corresponding to an amount of approximately 1 g to 100 g of carbon dioxide snow generated in the piece of meat 22, the valve 17 is closed, thus stopping the supply of liquid carbon dioxide. The device 1 is withdrawn from the piece of meat 22 and is now available for injecting another piece of meat.

[0032] The expansion of the carbon dioxide gas creates temporary gas cavities 26, 27 filled with carbon dioxide gas in the tissue of the piece of meat 22 around the outlet openings 11a, 11b; 12a, 12b, which is further promoted by the opposing arrangement of the outlet channels 11a, 11b; 12a, 12b. The carbon dioxide gas penetrates further into existing spaces in the surrounding tissue, thus ensuring uniform cooling of the meat tissue; in particular, the carbon dioxide gas can penetrate into the space between bone and muscle tissue, thus facilitating subsequent detachment of the meat tissue from the bone. The carbon dioxide gas gradually flows out of the piece of meat 22 through openings in the tissue, in particular through the puncture channel(s) created when the device 1 was inserted into the tissue. Suctioning or deliberately removing carbon dioxide gas from the treated piece of meat 22 itself is not necessary.In order to avoid an excessively high concentration of carbon dioxide in the ambient atmosphere, an extraction device (not shown here) can be provided which removes the carbon dioxide-enriched atmosphere from the surroundings of the piece of meat 22.

[0033] For ease of handling, the housing 2 is preferably made of plastic, and the front panel 4 is detachably attached thereto, for example by means of screws 28, 29. The front panel 4 itself is preferably made of metal, and the injection needles 5, 6 are firmly but detachably connected to it. This ensures, in particular, a rigid connection between the front panel 4 and the injection needles 5, 6 and, during use of the device 1, in particular prevents the injection needles 5, 6 from deflecting laterally relative to the direction of advance when penetrating the piece of meat 22. To facilitate operation, the housing 2 can also be equipped with a carrying eyelet (not shown here) for attaching a cable or similar device.

[0034] Furthermore, a device according to the invention can also be equipped with a single injection needle or more than two injection needles, for example, with three, four, or five injection needles, instead of the two injection needles 5, 6 shown here. An injection channel 7, 8 can also be fluidically connected to more than two outlet channels 11a, 11b; 12a, 12b, which open laterally from the injection needle 5, 6 along its longitudinal extension.

[0035] In the device 1 shown here, designed as a handheld device, an operator manually drives the injection needles 5, 6 into the piece of meat 22 to be treated using muscle power. A device according to the invention is preferably designed such that it can be moved by the operator with one hand, while simultaneously positioning or holding the piece of meat to be treated with the other hand. However, within the scope of the invention, an automatic feed device (not shown here) is also conceivable, which moves the device 1 as a whole 2 and drives the injection needles 5, 6 into the piece of meat.

[0036] List of reference symbols:

[0037] 1 device

[0038] 2 housings

[0039] 3 Handle

[0040] 4 Front panel

[0041] 5 Injection needle

[0042] 6 injection needle

[0043] 7 Injection channel

[0044] 8 Injection channel

[0045] 9 Distal end

[0046] 10 Distal end

[0047] 11 a, b Exit channel

[0048] 12 a, b outlet channel

[0049] 13 Hole

[0050] 14 Hole

[0051] 15 gas distributors

[0052] 16 Supply line for liquid carbon dioxide

[0053] 17 Valve

[0054] 18

[0055] 19 Control unit

[0056] 20 control panel

[0057] 21 detector means

[0058] 22 pieces of meat

[0059] 23 Data line

[0060] 24

[0061] 25 Surface

[0062] 26 gas caverns

[0063] 27 Gas Cavern

[0064] 28 screw

[0065] 29 Screw

Claims

Patent claims 1. Device for introducing carbon dioxide snow into fresh meat, comprising a housing (2) and at least one tubular injection needle (5, 6) arranged on the housing (2) and intended for insertion into a piece of meat (22), through the longitudinal extent of which an injection channel (7, 8) is guided, which opens out in the region of a distal end (9, 10) of the injection needle (5, 6) at at least one outlet channel (11a, 11b; 12a, 12b) and is fluidly connected at its inlet opening opposite the distal end (9, 10) of the injection needle (5a, 5b) to a supply line (16) connected to a source of liquid carbon dioxide.

2. Device according to claim 1, characterized in that the injection channel (7, 8) opens laterally at at least one outlet opening (11a, 11b; 12a, 12b) to a flow-tight tip of the at least one injection needle (5, 6).

3. Device according to claim 1 or 2, characterized in that an automatically controllable valve (17) is arranged in the supply line (16) for liquid carbon dioxide, which is operatively connected to a control unit (19) by means of which the supply of liquid carbon dioxide from the source into the piece of meat (22) can be regulated according to a predetermined program.

4. Device according to one of the preceding claims, characterized in that a plurality of injection needles (5, 6) are arranged at a distance from one another on the housing (2), each of which is connected to the source of liquid carbon dioxide via a gas distributor (15) arranged in the housing (2) or via separate lines.

5. Device according to one of the preceding claims, characterized in that the at least one injection needle (5, 6) is fixedly received in a front plate (4) of the housing (2).

6. Device according to one of the preceding claims, characterized in that a gas phase separator for separating gaseous carbon dioxide from the liquid carbon dioxide is provided in the supply line (16) for liquid carbon dioxide.

7. A method for introducing carbon dioxide snow into fresh meat using a device (1) according to one of the preceding claims, characterized in that the at least one injection needle (5, 6) equipped with an injection channel (7, 8) is introduced into a piece of meat (22), then liquid, pressurized carbon dioxide is introduced via the injection channel (7, 8) into the piece of meat (22), in which it expands to produce a mixture of carbon dioxide snow and carbon dioxide gas, then the injection needle (5, 6) is withdrawn from the piece of meat (22), while the introduced mixture of carbon dioxide snow and carbon dioxide gas remains in the piece of meat (22) and the carbon dioxide gas present in the piece of meat (22) escapes into the environment via openings and channels present in the meat tissue.

8. Method according to claim 7, characterized in that the flow rate of supplied liquid carbon dioxide is regulated as a function of the type of meat and / or a measured temperature of the piece of meat (22).

9. Method according to claim 7 or 8, characterized in that the supply of the liquid carbon dioxide takes place for a period of time between 0.1s and 3s, wherein during the expansion of the liquid carbon dioxide an amount of between 0.5 and 40g of carbon dioxide is introduced into the piece of meat (22) per injection needle (5, 6).

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