Abstract:
Embodiments of the invention provide a more efficient method for treating meat. In one embodiment, a rolling device includes several rolling units comprising in turn several rollers. To optimize the treatment process, sheeting with a degree of play is placed over the rolling units. Smoothing rollers can be provided at the end of the meat treatment nip.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
   This application is a continuation of, and claims priority under 35 U.S.C. § 120 from, International Patent Application No. PCT/EP2002/014494, filed Dec. 18, 2002, the entire disclosure of which is incorporated herein by reference. 

   BACKGROUND OF THE INVENTION 
   The invention relates to a meat rolling device for processing pieces of meat. The device especially serves for tendering fresh meat without bone portion in the field of food with simultaneous surface increase. 
   The structure of fresh meat processed with such a device is lastingly changed or relaxed (tendered), respectively, and the meat appears to be softer and more tasteful upon consumption. With fresh meat of very different kind, however primarily meat from cow and pork, lasting quality improvement is achieved. 
   From DE A 33 44 284, a device for treating meat or ham is known, which is provided with a rack, in which at least two oppositely rotating rollers spaced side-by-side are disposed, between which the material to be treated is passed. The rollers are formed as pressure rollers and the distance thereof is mutually adjustable. The pressure rollers can be exchangeably attached in the rack, for which each pressure roller is connected to the drive shaft via a quick coupling on the drive side and is supported in a bearing assembly detachably connected to the rack on the other side. The pressure rollers can be provided with ribs, knobs, projections and the like on their peripheral walls. The ribs extending at least partially over the length of the pressure rollers are at least approximately rectangular, acute or frustum-like in cross-section. The disadvantage of this meat processing device is that the meat cells of the processed piece of meat are destructed by squeezing such that very much cell liquid escapes and thereby the storability of the processed piece of meat greatly decreases. 
   By the rolling operating, effective surface increase of the processed piece of meat (e.g. escalope meat from pork, pork neck steaks, pork tenderloin, beef tenderloin and the like) results. By the employment of such a rolling device, manual meat beating is spared, wherein the fresh meat is flattened in its consistency by beating action with the corresponding working tool. Therein, massive escape of cell liquid occurs. This escape of cell liquid in turn results in contaminated working place and in measurable lost of weight of the processed fresh meat after beating of meat. Beaten fresh meat also easily dries out. 
   Another advantage of a rolling device over the usual meat beating is in the far less time and force requirement and the working manner far gentler to the body in processing meat. It has also taken care of the tendons and joints of the beating person partially overstressed in the usual beating operation. 
   In this context, from European patent application EP 00 121 256, a meat roller is known, which includes a roller jacket in the form of a cylinder and a plurality of roller teeth on the surface of the roller jacket, which substantially extend along the axis of the cylinder, wherein each one of the plurality of roller teeth has a first surface lying substantially on a plane through the axis of the cylinder, and a second surface disposed substantially perpendicularly to a first surface of a roller tooth adjacent in circumferential direction. 
   BRIEF SUMMARY OF THE INVENTION 
   A feature of the present invention is to provide a device, by which tendering of pieces of meat can be performed effectively, and the loss of cell liquid in processing is kept as low as possible. 
   According to an aspect of the invention, a meat rolling device includes at least two rolling mechanisms each having at least two parallel rollers, wherein the at least two rolling mechanisms face each other with formation of a nip, through which a piece of meat to be processed can be conveyed, and processing teeth on the surface of the rolling mechanisms extending substantially parallel to the roller axes, and which each have a first surface and a second surface, wherein the first surface of each processing tooth is disposed substantially perpendicularly to the second surface of a processing tooth adjacent in the circumferential direction. 
   According to another aspect of the invention, there is provided a method for tendering meat, including a meat rolling device as mentioned above, by portion-wise gripping a piece of meat to be processed by a tooth edge of the rolling mechanism provided with processing teeth, pressing the gripped portion of meat by a tooth side adjoining the tooth edge, and stretching the pressed portion of meat by hooking-in by means of the tooth edge. 
   By the formation of the processing teeth according to embodiments of the invention on the rolling mechanisms, the pieces of meat are portion-wise drawn into the nip. In the nip, the meat flows apart transversely to the processing direction according to the applied pressure, i.e. in axial direction of the rollers. Upon leaving the nip, the meat is drawn apart by the processing teeth, which diverge there and form barbs, thereby further tendering the piece of meat. 
   The processing teeth can be integrally connected to the respective roller. However, there is also the possibility that the processing teeth are disposed on the surface of a processing belt spanning the rollers of a rolling mechanisms. In the latter case, the rollers are only configured as guide rollers for the processing belt. This has the advantage that it can be exchanged more easily than the plural rollers. 
   Advantageously, each rolling mechanism respectively includes three or more rollers disposed linearly with respect to each other. Thereby, three roller pairs are substantially formed, by which the rolling operation can be performed more gently than with a single roller pair. 
   The nip formed by the rollers conveniently is variably adjustable. Thereby, different kinds of pieces of meat such as beefs olive and escalopes can be processed with equal efficacy. 
   Preferably, the nip is configured slightly V-shaped. Thereby, also the rollers disposed at the end in the roller chain or roller pairs maintain their intended effect, respectively, since the piece of meat becomes slightly thinner after each rolling operation. 
   The contact pressure of the rolling mechanisms with respect to each other can be adjustable. Thereby, very different sorts of meat can be accommodated. 
   An envelope can surround each of the roller mechanisms preferably with a predefined or adjustable backlash. Thereby, it can be controlled how far the piece of meat is drawn around a roller in the rolling operation. With the envelope, it can also be influenced to which extent the structure of the meat is destructed or changed by drawing, respectively. The envelope can have a plastic sheet and/or a textile material. It has the advantage that the teeth are not covered by torn-off pieces of meat in processing. Finally, this improves the processing quality and reduces the cleaning effort. 
   Advantageously, all of the rollers are separately driven. This causes the meat to be treated to be uniformly conveyed through the meat rolling device and the optionally employed envelope to obtain a longer lifetime. 
   Certain advantages also result if the plurality of processing or roller teeth, respectively, is uniformly disposed on the circumference of the roller jacket with or without clearance. Further, the roller teeth can extend over the entire jacket length or only a portion thereof, and the roller teeth can preferably be formed integrally from the roller body. Moreover, the meat rollers opposing with respect to processing are conveniently disposed substantially identically and anti-parallel with respect to the roller teeth. 
   For making a pleasant surface of the processed pieces of meat, they are conveniently smoothed at the end of processing. This is either effected by conveying the processed piece of meat reversely from the roller nip with reversing the processing direction. Alternatively, there is the possibility that smoothing rollers or rolling mechanisms with smoothing processing belts with or without teeth are disposed at the end of the processing nip such that the processing direction does not have to be reversed. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  a perspective view of a conventional meat rolling device; 
       FIG. 2  a side view of the meat rolling device; 
       FIG. 3  a partial cross-sectional view of the meat rolling device; 
       FIG. 4  a cross-section through a meat roller; 
       FIG. 5  a cross-sectional draft through a meat rolling device according to an embodiment of the invention; and 
       FIG. 6  a cross-sectional draft through an alternative meat rolling device according to another embodiment of the invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   First, a conventional meat rolling device is illustrated for better explaining the invention. According to  FIG. 1 , a conventional meat rolling device includes two parallel opposing toothed rollers  1 ,  1   a , wherein a differently broad roller nip or spacing  2  is adjustable between the two rollers. The desired contact pressure of the rollers on the fresh meat is regulated by changing the width of the roller nip  2 . Optionally, spring mechanisms may be appropriately used for this. 
   Both rollers are supported by slide bearings in the corresponding side parts on both sides. A side part pair  22  are rigidly fixed to the bottom plate  4 . The fixed roller  1  is supported on this side part pair  22 . The passive roller  1   a  disposed parallel to the fixed roller  1  is driven through the roller  1 . A side part pair  5 , between which the passive roller  1   a  is located, is movably attached to the bottom plate  4  by supporting bolts  6 . 
   An elevation inclination  21  of this supported side part pair  5  is achieved by eccentric rollers  7  according to  FIG. 2 , which are attached to a continuous shaft  8 . By rotating a lateral star wheel  80 , the side parts  5  are changed parallel in their elevation inclination  21  through the eccentric rollers  7 . Thereby, the roller nip  2  is changed in its width. Both rollers are each only toothed  9  in the longitudinal direction of the roller. The toothing  10  of the rollers according to  FIG. 3  extends according to their rotational direction  13  identically. As the tooth depth  11 , a standard measure of about 0.8 to 4 mm is vertically provided. It is noted that smaller and greater tooth depths are conceivable. 
   A roller tooth  23  to the adjacent roller tooth  23 ′ in circumferential direction results in a 90° angle (plus or minus 5° deviation) according to  FIG. 4 . The tooth surfaces can also be arched, which can be achieved by an appropriate shape of the milling tool for the roller. 
   The roller teeth  10  grip the fresh meat to be processed by opposite movement of the rollers,  1 ,  1   a  and move it, like the action of a harpoon, reliably into the roller nip  2 . Thereby, the feed of the rolling material is allowed in a straightforward manner. The number of the roller teeth per roller depends on the respectively selected roller diameter. With a roller diameter  12  of, e.g., about 10 cm, the number of teeth is typically about 20–25 pieces. The rollers  1 ,  1   a  are moved opposite to each other  13  in the working operation. Therein, the roller teeth  10  face each other. By providing an appropriate shape of the roller teeth and by the fact that the roller teeth  10  are only toothed in one direction, the pieces of meat also cannot attach and the pieces of meat also cannot accumulate. Thereby, also effective increase in surface area of the processed fresh meat is possible, because the rolling material can “extend” into the grooves of the roller teeth. In this rolling operation, the processed fresh meat is “kneaded thoroughly” through the roller nip  2 . By this working operation, the structure of the fresh meat is also relaxed or tendered. One advantageous feature of the device especially results from the particular configuration of the roller shape features  1 ,  1   a ,  9 ,  10 ,  11 ,  13  and  23 . 
   The axis  14  of the fixed roller  1  has a drive gear  15  on the one outer side of the side wall. The device is driven via a connection/intermediate piece from the drive gear  15  to the actual drive. The drive can be effected both mechanically, e.g., by a crank  16 , and electrically. 
   On the axis  17  of the passive roller  1   a , there is also located a gear  18  on the same outer side of the side wall  5  of the device, which is driven by the drive gear  15 . The course of movement of the gears  15 ,  18  is thereby opposite in the rotational direction. The entire device is attached to the subsoil  19 , e.g., through suction cups, clamps, screws, or similar attaching material. All of the used materials, of which the device is constructed, consist of food-compatible materials. The device can be easily disassembled and cleaned. 
   In  FIG. 5 , there is now illustrated a meat rolling device according to an embodiment of the present invention. Therein, the individual components substantially correspond to those described in connection with  FIGS. 1 to 4 , so that more detailed description can be omitted here. 
   The meat rolling device according to  FIG. 5  includes two rolling mechanisms  30  and  31 . Each one has three rollers  1 , respectively. A band-like envelope  40  passes over all of the rollers  1  of each of the rolling mechanisms  30  and  31 . However, the rolling mechanisms  30  and  31  can also be operated without the envelopes  40 . 
   The two rolling mechanisms  30  and  31  are disposed in a V-shaped arrangement. The angle to each other is variable. Moreover, also the distance between the two rolling mechanisms  30  and  31  is variably adjustable. In the present example, the first rolling mechanism  30  is rigid, while the second rolling mechanism  31  is movable. 
   The individual rollers  1  have teeth similar to those in  FIG. 4 . However, it is also possible to provide the individual rollers with different teeth or no teeth, such that, for example, only one side of the piece of meat is processed in a rolling operation. 
   In  FIG. 5 , three rollers  1  per rolling mechanism  30 ,  31  are illustrated. However, the number of rollers can also be reduced to two or increased to four, five, etc., per rolling mechanism. Moreover, the rollers do not have to be opposed in pairs in the rolling mechanisms. They can also be disposed in an offset manner, so that the piece of meat is conveyed in S-shaped manner through the rolling device. Further, two rollers can be provided in one rolling mechanism, and in the other rolling mechanism, only one roller can be provided. 
   In the embodiment, all of the rollers  1  are connected to each other and driven by a transmission not shown. However, principally, not all of the rollers have to be driven. Here, the drive can also be effected manually or by the aid of a motor. 
   According to  FIG. 5 , the meat rolling device is disposed vertically. However, it can also be horizontally installed in a meat processing equipment, for example, to remove pieces of meat from a conveyor belt. 
   For smoothing the processed piece of meat, the respectively lowermost roller of each rolling mechanism  30 ,  31  can be provided with a tooth alignment oppositely directed with respect to the other rollers. However, these rollers can also be formed without processing teeth. 
   The alignment of the roller teeth and the rotational direction of the rollers at least of the two upper roller pairs of  FIG. 5  corresponds to that of  FIG. 3 . 
   In  FIG. 6 , an alternative meat rolling device according to another embodiment of the invention is illustrated in cross-section. In this case, each rolling mechanism  30 ,  31  comprises two rollers  41  only configured as guide rollers. A processing belt  42  passes over them, which has substantially the same teeth as illustrated in  FIG. 4 . The alignment of the teeth of rollers opposed with respect to the processing nip corresponds to that of  FIG. 3 . 
   A smoothing roller pair with the rollers  43  follows the rolling mechanism  30 ,  31 . In this embodiment, the smoothing rollers  43  do not have any processing teeth. 
   Any combinations of the rollers and rolling assemblies illustrated in context with  FIGS. 5 and 6  are conceivable. Also, the meat rolling device is not restricted to three roller pairs. 
   It is to be understood that the above description is intended to be illustrative and not restrictive. Many embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the appended claims along with their full scope of equivalents.