US3520011A - Method and apparatus for removing hair roots from pork bellies - Google Patents

Description

J y 0 w. w. LEHMAN ETAL 3,520,011

METHOD AND APPARATUS FOR REMOVINGi HAIR ROOTS FROM PORK BELLIES Filed May 27, 1968 I 2 Sheets-Sheet 1 WILLIS w. LEHMAN ELWOOD A. OLSON LEO E. O'NEAL' INVENTORS BY WJ M AGENT y 1970 w. WQLEHMAN'" ET AL 3,520,011

METHOD AND APPARATUS FOR REMOVIN G HAIR ROOTS FROM PORK BELLIES Filed May 27. 1968 z Sheets-Sheet 2 FIG 3 WILLIS w. LEHMAN ELWOOD A. OLSON LEO E. O'NEAL INVENTORS AGENT United States Patent 3,520,011 METHOD AND APPARATUS FOR REMOVING HAIR ROOTS FROM PORK BELLIES Willis W. Lehman, Glenville, and Elwood A. Olson and Leo E. ONeal, Albert Lea, Minn., assignors to Wilson and C0., Inc., Chicago, llll., a corporation of Delaware Filed May 27, 1968, Ser. No. 732,177 Int. Cl. A22b /08; C14b 17/00 US. Cl. 171 7 Claims ABSTRACT OF THE DISCLOSURE Disclosed are a method and apparatus for removing hair roots from skinned pork bellies by impinging upon the bellies a spray of hot water under pressure.

FIELD OF THE INVENTION This invention relates to butchering, and more particularly to a method and apparatus for removing hair roots from skinned pork bellies.

DESCRIPTION OF PRIOR ART In the commercial butchering of hogs, the carcasses are scalded and passed through a dehairing machine where substantially all the hair is removed from the surface of the hogs skin by the beating action of steel-tipped rubber paddles. This mechanical process may be supplemented with singeing and manual shaving with a knife. However effective these processes may be in removing the hogs hair from the surface of the skin, some hair connected to hair roots remains embedded beneath the skin. Previously, this problem was particularly prevalent in the so-called hardhair season, principally July through October, during which time the hogs develop a new coat of hair, the new hair being more difiicult to remove. Recently, because pigs are farrowed the year round, the hard-hair season encompasses the entire calendar year. Since the hair roots occur just beneath the epidermis or outer skin layer of the hog, their presence is not a particular problem in the preparation of the hams and loins because a substantial amount of fat is removed from these parts of the hog along with the outer skin layer. However, the removal of hair roots from skinned pork bellies has been a difficult and costly problem in the hog butchering industry. It is desired that as much of the belly be saved for curing as possible. Consequently, the bellies are skinned so that, in general, only the epidermis is removed, exposing the pebble fat or dermis of the pork belly, which contains the hair roots. To satisfy the requirements of the US. Department of Agriculture and to produce a saleable prodnot, these hair roots must be removed. In the past, the only method known for removing hair roots from pork bellies has been hand scraping with a knife or other sharp instrument adapted for scraping. This method sulfers from two serious disadvantages. First, removal by scraping requires that some fat be removed along with the hair roots. This fat containing the hair roots is waste, to the extent that it must be sold as inedible fat rather than bacon. Second, scraping is arduous and time-consuming work requiring additional laborers on the production line, the number of which vary during the year, depending upon the severity of the hair root problem. Thus, the need for removal of the hair roots has caused a serious restriction on productivity.

In accordance with this invention, hair roots are removed from skinned pork bellies by impinging upon the bellies a spray of hot water under pressure. The bellies are positioned on a mesh conveyor belt and pass by a spray head at least as wide as the belly which directs jets of hot water onto the surface of the bellies, effectively 3,520,011 Patented July 14, 1970 washing the hair roots from the belly. To contain the hot water spray, the spray head and conveyor are provided with a cover which is vented to carry off condensed water vapor or steam.

Accordingly, it is an object of the present invention to provide a method and apparatus for rapidly and economically removing hair roots from skinned pork bellies.

Another object is to provide a method for removing hair roots from skinned pork bellies which eliminates waste.

A further object is to provide a method for removing hair roots from skinned pork bellies which requires less labor and increases productivity.

Other objects and advantages will be apparent from the specification and claims and from the accompanying drawing illustrative of the invention.

In the drawing:

FIG. 1 is a perspective view of an embodiment of apparatus according to the invention comprising a mesh conveyor belt, a spray head located thereon, and a cover disposed over the spray head and a portion of the belt;

FIG. 2 depicts the apparatus shown in FIG. 1 and further provided with switching means and means for adjusting the spray head in response to variations in thickness of the pork bellies;

FIG. 2a is a schematic view of one arrangement of the water supply control;

FIG. 3 is a side view illustrating the operation of the spray head of the apparatus shown in FIG. 2;

FIG. 4 is a view showing water from one embodiment of the spray head striking a pork belly;

FIG. 5 is a cross-sectional view of the spray head shown in FIG. 4;

FIG. 6 is a view showing water from another embodiment of the spray head striking a pork belly; and

FIG. 7 is a cross-sectional view of the spray head shown in FIG. 6.

Referring now to FIG. 1, the apparatus of the invention comprises a spray head 1 for directing hot water under pressure onto pork bellies 2 to be cleaned. The apparatus further comprises an endless conveyor belt 3 supported by frame 4 and located beneath the spray head for conveying the skinned pork bellies to and away from the spray head. A mesh belt is preferred because it provides a stable support for the pork bellies as well as ensuring that the pork bellies remain in a fixed position when struck by the spray. If a non-perforated belt were used, it would accumulate water, thus causing the bellies to float and slide about. The mesh belt provides the further advantage of permitting the water to pass directly therethrough and out a drain. Motive power is imparted to the endless, mesh conveyor belt 3 by gears 5, driven by a suitable motor, not shown.

Because of the high pressure and temperature of the spray, it is preferable to provide a suitable cover for the spray apparatus '1. In the embodiment shown, the cover is essentially a rectangular, bottomless enclosure the same width as the frame 4 and having a top 6 and positioned over the spray head 1 and mesh belt 3 so as to cover the spray head and at least the pork belly being sprayed. Swinging doors 7 and 8 are located in the sides of the enclosure perpendicular to the direction of travel of the belt, extend across the width of the belt, and permit the pork belly to pass into and out of the enclosure, but otherwise remain closed to retain the Water inside the enclosure. To further prevent the escape of the spray from the enclosure, baffles 9 and 10 are mounted inside the enclosure and parallel to those sides which have doors 7 and 8. The bafiles are as wide as the inside of the enclosure and extend from the top 6 to the belt 3. The sections 11 and 12 of each bafile adjacent the belt are hinged to permit the pork belly to proceed along with the belt, but otherwise remain perpendicular to the belt to promote retention of the spray within the enclosure. The cover has a vent or chimney 13- on the top 6 to remove the condensed water vapor or steam which forms during the use of the device.

The apparatus further includes means (not shown) including a pump for supplying hot water under pressure through water supply line 14 to the spray head 1. The apparatus is also provided with gauges 1 and 16 in the water supply line 14 near the spray head for measuring the water pressure and temperature respectively. In the example shown, the spray head is mounted at a fixed distance above the belt by means of, for example, a first, upstanding member 17 footed on one side of the frame and a second, upstanding member 1 8 similarly footed on the opposite side of the frame, the spray head being attached to the upstanding members 17 and 18 by suitable clamps, such as 19. One skilled in the art will readily perceive modes of rendering the height of the spray head above the belt adjustable at will, if so desired. The spray head is also rotatable with respect to its mounts.

Since frequently not all pork bellies contain hair roots after skinning, it may be desirable to expose to the water sprays only those bellies which do require removal of hair roots, thus conserving water. In accordance with the embodiment shown in FIG. 2, selective control is achieved by installing a triggering device 20 along one side of the enclosure parallel to the directional of travel of the belt before the spray head 1, and near enough to the belt 3 to touch a pork belly of minimum thickness. The triggering device extends a short distance from the side of the cover so that contact with a passing pork belly activates the device, thus turning on the water. The

triggering device is arranged so that, after the belly has passed the spray head, the water flow is shut off. Those pork bellies not requiring hair root removal are positioned on the conveyor belt, by an operator, toward the side opposite the triggering device so they do not come in contact with the trigger, thus leaving the supply of water shut off. Through this method, considerable savings in Water usage can be achieved.

While many means for controlling the water supply will be apparent to those skilled in the art, one suitable arrangement is depicted schematically in FIG. 2a. The triggering device 20 is affixed in the cover all by flexible mounting means 31, and is mechanically connected to a micro-switch 3-2 which activates a solenoid 33 controlling a three-way valve 34 in the water supply line from the pumps to the spray head. When no pork belly is in contact with the triggering device 20, the micro-switch 32 is open and the valve 34 reciroulates the water back to the pump. When a pork belly touches the triggering device, the micro-switch is closed, thus activating the solenoid 3-3, which causes the valve to direct water from the pump to the spray head. After the pork belly has passed by the triggering device, the micro-switch 32 returns to its normally open position, which deactivates the solenoid and shuts off the supply of water to the spray head.

The apparatus preferably further comprises means for adjusting the spray head to respond to variations in thickness of the pork bellies. In the embodiment shown in FIG. 2, a roller 21 is fixedly mounted in parallel, spaced relation in front of the spray head by connecting rods 22. The nozzle portion of the spray head to which the connecting rods attach is freely rotatable with respect to the ends of the spray head, which is firmly attached to the frame 4, as described above. As more fully illustrated in FIG. 3, as pork of increasing thickness is encountered by the roller 21, the nozzles are turned upward or in a clockwise direction so that the distance from the nozzles to the surface of the pork belly remains substantially the same. As is apparent from FIG. 3, as the roller 21 is raised, the angle of the spray to the belly decreases slightly. Accordingly, the length of the connecting rods 22, which generally determines the angle of the spray, is chosen so as to provide the optimum angle for the belly of median thickness.

Preferably, the nozzles of the spray head are of the type which produce a fine spray and thus use a relatively low volume of water. In the embodiment shown in FIG. 4, the spray head comprises thirteen nozzles 41, each having a 0.062 inch diameter orifice and arranged in a row along a 15 inch section of a 1% inch internal diameter water pipe 42. The particular nozzles described each produce a fan spray 43 having a width of 25 degrees. The mounting of a nozzle 41 in the pipe 4-2 is further illustrated in FIG. 5.

Preferably, interference of the sprays with each other, which reduces the strength of their impact upon the pork belly, is avoided. In accordance with the particular arrangement shown in FIG. 4, the fans overlap only slightly to produce a continuous section of spray at the point of contact with the pork belly 44. If the nozzles are not disposed in the same vertical plane, however, for example if they are staggered, the sprays can overlap without interfering.

In an alternative embodiment of the spray head shown in FIG. 6, the water pipe 61 contains a narrow slit or aperture forming an elongate nozzle 62 which produces a continuous, thin sheet of spray 63 which strikes the pork belly 64 uniformly. FIG. 7 is across-sectional view of the water pipe 61 showing the slit in greater detail. The elongate nozzle may be formed in a section of the pipe, for example, by cutting a slit or aperture 71 in the pipe and inserting in the slit 71 a nozzle 62.

In operating the device of the invention, the temperature of the water used should be about to F. It has been observed that, at temperatures below 140 F., the effectiveness of the device is increased as the water temperature is increased. It is believed that a water temperature of at least 130 F. is necessary to release the hair follicle, or root, from the fat in which it is imbedded. On the other hand, water temperatures substantially in excess of 140 F. have been observed to detrimentally affect the fat.

The angle of the spray through the mesh belt should be 25-45 degrees from the perpendicular, measured from the surface of the mesh belt and toward the approaching pork belly. The optimum angle is about 35 degrees. The spray head is located a few inches from the mesh belt, for example 4 to 5 inches. Pork bellies can vary in thickness form 1 /2 inches to as much as 4 inches. Accordingly, it will be apreciated that the distance from the top surface of the pork belly to the spray head will vary between 1 and 3 /2 inches, in proportion to the thickness of the pork belly. If it is desired to optimize the distance from the spray head to the top surface of the pork belly, the pork bellies are either graded according to thickness or the apparatus is provided with means for adjusting the spray head in response to the thickness of the pork 'belly to maintain the optimum distance, as, for example, by the means shown in FIGS. 2 and 3.

It is apparent that when the pork bellies are skinned to remove an outer portion of the skin only, exposing the pebble fat, more hair roots remain on the pork belly than when the belly is skinned more deeply. Deeper skinning, however, removes more fat and thus results in a reduction of yield, yield being defined as the ratio of the weight of the belly before skinning to the weight of the belly after curing.

The water pressure at the spray head may be varied between 500 and 900 pounds per square inch (p.s.i), depending upon the rate of travel of the bellies past the spray head and the severity of the hair root problem, i.e., the density of the hair roots remaining in the pebble fat. For normal hair root conditions, the rate of travel of the mesh belt is typically 30 feet per minute and the pressure is about 700 pounds per square inch while employing the spray head shown in FIG. 4, which uses 33 gallons of water per minute. It is preferred to increase the water pressure rather than to increase the volume of the water because a high volume of water tends literally to wash away fat, whereas a fine, low-volume, highpressure spray tends only to remove the hair roots or follicles. Thus it is seen that a surprising result is achieved in accordance with the present invention. While one might reasonably expect that an effert to remove the relatively hard and dense hair follicles, with stubs of air attached, from the soft pebble fat of the pork belly by means of a spray of water, would result simply in loss of pork fat and leave the hair roots imbedded in the belly, or require the ablating away of the fat surrounding the follicles and susbtantial concomitant product loss. Contrary to such expectations, however, the removal of hair roots in accordance with the present invention results in no loss of fat from the pork belly.

The speed at which the mesh belt travels can, of course, be varied to match the capacity of the workers and the rate of operation of other parts of the production line and adjusted according to the severity of the hair root problem. Typically, the rate of travel varies from 12 to 40 feet per minute. At these rates, a belly requires from 3 to 6 seconds to pass through the spray.

It has been observed that the apparatus of the invention shown in FIG. 1 performs most effectively when the pork bellies are moving past the spray head contiguously. No complete explanation is known for this fact, but it is believed that, when the pork bellies are so arranged on the mesh belt, they may have a damping effect on the turbulence of the water spray beneath the hood and thus permit the spray to operate with less interference. However, the phenomenon may also be attributable to the possible, pre-warming efiect produced by the hot water flowing and splashing forward (in a direction opposite the direction of belt travel) from the spray from one belly to the next.

From the above, it may be seen that substantial savings can be achieved through the use of the present invention, both in the increase in yield and the reduction of the per-unit cost of labor. It is no longer necessary to scrape the pork bellies to remove the hair roots or to skin deeply to take out the hair roots along with the skin, both of which previously necessary operations, reduce the amount of saleable fat. Using the process of the invention, there is essentially no loss of weight of the skinned belly. Moreover, while it might be expected that pork bellies contacted with hot water would be more susceptible to rancidity, peroxide-value tests show that pork bellies cleaned by the process of the invention showed less rancidity than bellies cleaned by manual scraping. Since the time of contact of the belly with the water is of such short duration, the rise in temperature of the surface of the belly is very slight. Normally, the temperature rise is 7 F. in the first A inch of the belly only. The belly may be quickly and easily recooled to curing temperature.

It is apparent that other variations and modifications may be made without departing from the present inven- 6 tion. Accordingly, it should be understood that the forms of the present invention described above and shown in the accompanying drawing are illustrative only and not intended to limit the scope of the invention.

What is claimed is:

1. A method of removing hair roots from a skinned pork belly comprising the step of spraying the belly with water at a temperature of -140 F. under 500900 p.si. pressure from a spray head at least as wide as the belly and located a few inches from the belly, and at an angle of 25-45 degrees from the perpendicular measured from the surface upon which the belly rests.

2. The method according to claim 1 wherein the temperature is about F., the pressure is about 700 p.s.i., and the angle is about 35 degrees.

3. A method of removing hair roots from a skinned pork belly comprising the steps of:

conveying the belly on a mesh belt past a spray head at least as wide as the belly and located a few inches from the belly, and

impinging upon the belly, from the spray head, water at a temperature of 130-140 F., under 500900 p.s.i pressure, and at an angle of 25-45 degrees from the perpendicular, measured from the surface of the mesh belt and toward the approaching belly.

4. The method according to claim 1 wherein the temperature is 140 F. the pressure is 700 p.s.i., and the angle is about 35 degrees.

5. Apparatus for removing hair roots from a skinned pork belly comprising:

a mesh belt for conveying the belly;

a spray head disposed a few inches above the belt, at least as wide as the pork belly, and positioned so as to direct water at an angle of from 25-45 degrees from the perpendicular, measured from the surface of the belt and toward the approaching belly; and

a pump for providing a supply of hot Water to the spray head and under pressure of 500-900 p.s.i. at the spray head.

6. Apparatus according to claim 5 further comprising means for selectively controlling the supply of water.

7. Apparatus according to claim 5 further comprising means for adjusting the position of the spray head in response to the thickness of the pork belly, whereby an optimum distance between the spray head and mesh belt is maintained.

References Cited UNITED STATES PATENTS 2,389,404 11/ 1945 Barker l7l 1.1 2,412,338 12/1946 Jasper l747 2,635,284 4/1953 Hunt 17-1 1.1 2,783,496 3/1957 Thomas l747 LUCIE H. LAUDENSLAGER, Primary Examiner U.S. Cl. X.R. l747

Images