Abstract:
Pasta filata cheese, such as mozzarella and provolone, is molded and chilled by delivering the warm, plastic cheese through a cheese inlet port into a plurality of molds at an inlet station. A fluid, such as chilled water, is circulated around the molds to cool the pasta filata cheese therein. After cooling to some degree, force is applied to the upper surface of the cheese in each mold to prevent a depression from forming in that surface. Thereafter upon cooling for a desired amount, the pasta filata cheese is ejected from the plurality of molds at an outlet station.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    Not Applicable 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not Applicable 
       BACKGROUND OF THE INVENTION 
       [0003]    1. Field of the Invention 
         [0004]    The present invention relates to apparatus and methods for making pasta filata cheeses, such as mozzarella and provolone; and more particularly to techniques for ensuring uniformly molded loaves of such cheese. 
         [0005]    2. Description of the Related Art 
         [0006]    Pasta filata (plastic curd) cheeses are Italian type cheeses in which the curd is worked to develop a fiber or string-like texture providing an elasticity to the finished cheese. This type of cheeses are kneaded while the curd is in the plastic state to develop a desired texture. The kneading is performed by a motor-driven cooker/stretcher that has an auger within a trough, in which the cheese curd is stretched and compressed as it is conveyed along the length of the trough. The kneading process is conducted at about 122° C. to impart plasticity to the cheese, but below the melting point of the cheese where the fiber structure of the cheese would be lost through melting. 
         [0007]    After the desired texture and structure of the cheese has been developed, the kneaded, plastic cheese mass is transferred to a molder/chiller apparatus in which the mass is divided into 7 to 12 kilogram loaves and cooled to approximately 40° C. The cooled cheese loaves typically are then transferred into a tank containing cold brine in which the loaves of cheese float to prevent deformation until the cooling process is completed. e.g., when center core of the cheese loaf has reached approximately room temperature. At that point the cheese loaf is removed from the brining tank and packaged. 
         [0008]    Occasionally while the cheese mass is cooling in the molder/chiller apparatus, a depression formed in the upper surface of the cheese loaf. Such depressions, or dimples, may form in up to twenty percent of the loafs at reasonable production speeds of the molder/chiller apparatus. The depressions create non-uniform loaves that are objectionable to the end-user who cannot produce cheese slices from that end of the loaf. Although the incidents of depressions can be reduced by slower speeds of the molder/chiller apparatus, that adversely affects the rate of production of the cheese loaves. 
         [0009]    It is thus desirable to provide a molder/chiller apparatus that significantly reduces or eliminates instances of depressions forming in the surface of the cheese loaf. 
       SUMMARY OF THE INVENTION 
       [0010]    An apparatus for molding and chilling pasta filata cheese includes a plurality of molds, preferably each mold has an upper surface with an opening there through. A cheese inlet port is provided for delivering a warm, plastic mass of pasta filata cheese into the plurality of molds at an inlet station. A cheese outlet port is provided to enable the pasta filata cheese to pass out of the plurality of molds at an outlet station. A transporter moves the plurality of molds between the inlet and outlet stations and a plumbing system circulates a fluid around the molds travelling between the inlet and outlet stations to thereby cool the cheese. 
         [0011]    A press applies force through the opening onto the pasta filata cheese as the plurality of molds travel between the inlet and outlet stations. Application of the force inhibits a depression from forming on the upper surface of the pasta filata cheese while cooling within the mold. 
         [0012]    In one embodiment of the invention, the plurality of molds include a mold housing within which a plurality of mold tubes are located for receiving the plastic pasta filata cheese. The mold housing forms a cavity around the plurality of mold tubes and the plumbing system circulates the fluid through the cavity. 
         [0013]    In another aspect of the invention, the press comprises a member that is lowered adjacent to the upper surfaces of the plurality of molds to apply the force onto the pasta filata cheese. For example, a plug may be inserted in each mold on top of the cheese and the member contacts the plugs to apply the force. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is an exploded perspective view of an example of a cheese molder/chiller with which the present invention may be employed; 
           [0015]      FIG. 2  is a perspective view of the cheese molder/chiller showing the components of a press according to the present invention; and 
           [0016]      FIG. 3  is a cross section view through one mold housing of the molder/chiller. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0017]    Although the present invention is being described for use with a rotary molder/chiller, the inventive concepts can be used with other types of equipment for chilling molds containing cheese. References herein to directional relationship and movement, such as top and bottom or clockwise, refer to the relationship and movement of the components in the orientation illustrated in the drawings, which may not be the orientation and motion of the components as attached to other machinery on which the present invention is used. 
         [0018]    With initial reference to  FIGS. 1 and 2 , a molder/chiller  10  includes a number of arcuate mold housings  12 , each supporting a plurality of vertically extending mold tubes  14  opening through top and bottom plates  15  and  16  of the mold housing. Each mold tube  14  forms a mold that defines the shape of a cheese loaf to be produced and each loaf typically weighs 7 to 12 kilograms. The mold housings  12  provide a cavity  17  around the mold tubes  14  thereby forming a water jacket through which chilled water flows to cool cheese that has been injected into the mold tubes. The chilled water flows through a plumbing system  19  between a water cooling device (not shown) and the mold housings  12 . The terms “chilled water” and “cooled fluid” used herein refer to a liquid that has a temperature less than the temperature of the cheese within the mold tubes  14 . It should be understood that other fluids than water may be used to cool the cheese within the mold tubes  14 . 
         [0019]    The bottom plate  16  of each mold housing  12  extends beyond the vertical walls of the mold housing  12  to provide a radially extending outside flange  20  and circumferentially extending side flanges  22 . A plurality of vertical index pins  24 , that project upward from the outside flange  20  aligned with each row of the mold tubes  14 , are used for indexing rotational motion of the mold housings  12 , as will be described. 
         [0020]    The mold housings  12  fit together to form an annular wheel  11  that extends horizontally about a central axis  18 . The mold tubes  14  are arranged in rows along radial lines passing through that axis  18 . When the mold housings  12  are assembled together into the wheel  11  and placed on a carrier surface  30 , the wheel&#39;s outer periphery formed by the outer flanges  20  engages guide rollers  37  at the perimeter of the carrier surface to guide rotation of the mold housings  12  in a regular orbit about axis  18 . 
         [0021]    The carrier surface  30  is supported above the factory floor by support beams  32  so as to allow a cheese auger assembly  34  and brine tank  36  to be placed underneath the carrier surface  30 . As the mold housings  12  move on carrier surface  30  in clockwise direction about the central axis  18 , they pass over radially extending cheese inlet ports  38  having equal spacing and size to one radial row of the mold tubes  14  and their apertures  35  in the bottom plate  16 . The cheese inlet ports  38  are formed by an upward extending portion  33  of the cheese auger assembly  34  which receives cheese through a hopper  40  and forces the cheese through the length of an elongated housing of the cheese auger assembly by means of an internal motor-driven auger and then upward through the cheese inlet ports  38 . The cheese inlet ports  38  may be replaced for different sizes and shapes of mold tubes  14  and define an inlet station  39  through which each of the rows of mold tubes  14  pass. As shown in  FIG. 2 , a filler plate  44  is mounted above the mold housings  12  at the inlet station  39  to limit the amount of cheese that can be injected through the inlet ports  38  into the mold tubes  14 . This filler plate  44  prevents cheese from overflowing the mold tubes  14 . 
         [0022]    Displaced slightly counterclockwise from the cheese inlet ports  38  as seen in  FIG. 1  is a cheese outlet port  42  positioned over the brine tank  36  to receive finished molded loaves of cheese. The cheese outlet port  42  defines an outlet station  57 . With additional reference to  FIGS. 2 and 3 , a pneumatic cylinder set  46 , having plungers  48  aligned with the centers of the mold tubes  14  in one radial line, is positioned above the outlet station  57 . The plungers  48  are operated to push downward on the plugs  50  to eject formed loaves of cheese  52  through the cheese outlet port  42  in the carrier surface  30 . Each plug  50  has a lateral tab or other element that prevents the plug from being ejected from the associated mold tube  14  through the bottom plate  16 . 
         [0023]    As shown in  FIGS. 1 and 2 , a mold driver  54  rotates the wheel  11  of mold housings  12 . The mold driver  54  for example may comprise a pneumatic cylinder  56  positioned to extend an arm  58  tangentially to the rim of the wheel so formed by flanges  20 . The distal end of the arm  58  includes a pawl  60  that engages the index pins  24  one at a time to rotate the mold housings  12  as the arm is extended from the cylinder  56 . As the arm  58  is retracted into the cylinder  56 , the pawl  60  moves to engage the next index pin  24  in the counterclockwise direction around the mold housing wheel  11 . Then extending the arm  58  from the cylinder  56  again pushes the wheel  11 , so that the next radial row of mold tubes  14  aligns with the cheese inlet ports  38 . In that position of the wheel  11 , another radial row of mold tubes  14  aligns with the cheese outlet port  42 . The cylinder  56  is periodically cycled in this manner to rotate the mold housing wheel  11  around its orbit in steps. For example, the pneumatic cylinder  56  may be operated every 30 to 60 seconds depending on the characteristics of the cheese being produced. The period of that cycling is selected to ensure that the cheese in the mold tubes  14  has been cooled sufficiently by the time that row of mold tubes reaches the outlet port  42 . Although the exemplary mold driver  54  comprises a pneumatic cylinder  56  and an arm  58 , other mechanisms, such as a motor, for rotating the mold housing wheel  11  can be used. 
         [0024]    The cheese auger assembly  34 , pneumatic cylinders  46  and  56 , and other components are operated by a control system  66  that includes an air compressor, control valves, sensors, and a computerized controller. 
         [0025]    The molder/chiller  10  components described thus far are typical of prior commercially available apparatus for molding and chilling loaves of Italian style cheese. 
         [0026]    The molder/chiller  10  is enhanced by a pressing station  68  at which a mold press  70  is located above the wheel  11  of mold housings  12  between the inlet and outlet stations  39  and  57  in the direction of travel of the mold housings. For example, the mold press  70  may be located between 180° and 270° clockwise, i.e., in the direction of wheel rotation, around the carrier surface  30  from the inlet ports  38 , however another location may be used depending on the cheese characteristics. The mold press  70  comprises an arcuate plate  72  that generally matches the shape of the upper surface of one of the mold housings  12 . The arcuate plate  72  is mounted to the distal end of a piston shaft  75  projecting from a pneumatic cylinder  74  that is attached to a support structure  76  secured to the factory floor and optionally also to the factory ceiling. Operation of the pneumatic cylinder  74  by the control system  66  raises and lowers the plate  72  with respect to the upper surfaces of a mold housings  12  and the mold tubes therein. The plate  72  is raised upward to allow the mold housing wheel  11  to rotate about around its orbit in response to operation of the mold driver  54 . 
         [0027]    With reference to  FIG. 3 , when wheel  11  of mold housings  12  remains stationary between times when the mold driver  54  is activated, the pneumatic cylinder  74  is operated to lower the plate  72  on top of the mold tubes  14  there below. There is a plug  50  on top of the cheese  52  in each mold tube  14 . The plugs  50  extend out of the mold tubes  14 , projecting slightly above the upper surface of the mold housing  12 . When lowered, the plate  72  of the mold press  70  contacts the plugs. The weight of the plate  72  (e.g., 114 kilograms) and the force from the pneumatic cylinder  74  and piston shaft  75  result in a combined downward force from approximately 1 psi to approximately 5 psi of (6.894 and 34.470 kilo-pascals) being applied to each plug  50 . This force prevents a depression from forming in the upper surface of the cheese  52  in each of the mold tubes  14 . Thus the precise amount of force that is sufficient to preclude a depression from forming may vary from the above force range. 
         [0028]    Application of the force by the mold press  70  also enables the rotation speed of the wheel  11  to be increased from that of conventional rotary molder/chillers, thereby increasing the throughput of the molder/chiller  10  without creating depressions in the cheese loaves. 
       Industrial Applicability 
       [0029]    The apparatus  10  described above is used to mold and chill pasta filata cheese. The cheese that has been processed in a cooker and stretcher machine is conveyed as a large homogenous mass into the hopper of the cheese auger assembly  34  in  FIG. 1 . The mold driver  54  periodically rotates the wheel  11  of mold housings  12 . When a row of empty mold tubes  14  has moved into alignment with the inlet ports  34 , as detected by a sensor, the controller  66  activates the auger assembly  34  to force cheese through the inlet ports and into those tubes. At that time, the cheese enters the mold tubes and forces the plugs  50  therein upward. When the plugs  50  contact the filler plate  44  above the mold housing  12 , the force exerted on that plate is sensed thereby providing an electrical signal to the controller  66 , indicating that the mold tubes  14  are now filled with cheese. In response to that signal, the controller terminates the operation of the auger  34 . 
         [0030]    The mold driver  54  continues to step the mold housing wheel  11  in a clockwise direction around the central axis  18 . With each step another radial row of mold tubes  14  is filled with cheese. As the wheel  11  rotates, the plumbing system  19  is circulating chilled water through each of the cheese housings  12  and specifically through the cavity  17  around the mold tubes  14 . The circulation of chilled water draws heat from the cheese within the mold tubes, thereby reducing the temperature of that cheese. 
         [0031]    After a mold housing  12  containing cheese has traveled at least halfway around the path between the inlet station  39  and the outlet station  57 , the mold housing passes beneath the press  70 . While the wheel  11  remains stationary in between steps of its motion, the controller  66  activates the pneumatic cylinder  74  which lowers the plate  72  onto the plugs  50  that project slightly above the upper surface of the cheese tubes  14 . This applies force to the plugs which force is transferred to the upper surface of the cheese  52  within each of those mold tubes. The plate  72  remains in that position until the next time that the mold driver  54  is to be activated. Just prior to that activation, the controller  66  operates the pneumatic cylinder  74  of the press  70  to raise the plate  72  upward away from contact with the plugs  50 . The mold driver  54  then rotates the wheel  11  of mold housings  12  another step. Once the wheel  11  has stopped moving, the controller  66  operates the pneumatic cylinder  74  to again lower the plate  72  onto the plugs  50  extending from the cheese tubes  14  beneath that plate. 
         [0032]    In the exemplary system illustrated herein, a given radial row of cheese tubes remains underneath the press plate  72  for five steps of the rotation of the cheese housing wheel  11 . Therefore, pressure is applied to the upper surface of the cheese within each of those tubes for between approximately 2.5 and 5.0 minutes, depending upon the rotational speed of the wheel. In this manner, force is applied to the upper surfaces of the cheese within each mold tube  14  thereby inhibiting a depression from forming in the upper surface of the cheese and producing a uniformly shaped loaf of cheese. 
         [0033]    The period between steps of the rotation provided by the driver  54  is selected depending upon the characteristics of the cheese being produced so that the cheese will have cooled sufficiently upon reaching the outlet port  42 . This cooling ensures that each loaf upon being ejected from the mold tubes  14  into the brine tank  36  will retain its uniform shape. To accomplish that ejection, when rotation of the mold housing wheel  11  stops, the controller  66  activates the pneumatic cylinder set  47  located above the outlet port  42 . That activation lowers the plungers  48  into contact with the plugs  50  in each of the cheese tubes  14  that are aligned with the outlet port  42 . Continued downward motion of the plungers  48  forces the plugs  50  through the cheese tubes  14 , ejecting the loaf of cheese  52  therein through the outlet port  42  and into the brine tank  36 . 
         [0034]    This process of incrementally stepping the rotation of the mold housing wheel  11  goes on. The now empty row of cheese tubes  14  continues to move clockwise from the outlet port  42  and the outlet station  57  eventually becoming aligned again with the inlet ports  38  at the inlet station  39  to receive new cheese from the auger assembly  34 , thereby repeating the molding process. 
         [0035]    The foregoing description was primarily directed to one or more embodiments of the invention. Although some attention has been given to various alternatives within the scope of the invention, it is anticipated that one skilled in the art will likely realize additional alternatives that are now apparent from disclosure of embodiments of the invention. Accordingly, the scope of the invention should be determined from the following claims and not limited by the above disclosure.