GB1575351A - Stuffing of food casings - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO THE STUFFING OF FOOD CASINGS (71) We, UNION CARBIDE COR PORATION, a corporation organized and existing under the laws of the State of New York, United States of America, whose registered office is, 270 Park Avenue, New York, State of New York 10017, United States of America, (assignee of VYTAUTAS KUPCIKEVICIUS and ANTON LEROY MIKA), do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to method and apparatus for sizing control in food casing stuffing.

In particular the invention is concerned with sizing discs for use with and in apparatus for controlling product diameter uniformity in the production of stuffed casing food products, the sizing discs having casing inner surface contacting rim widths which bear a dimensionally specific relationship to the disc diameter and to the desired product diameter for respective given or preselected materials of disc construction.

In the meat packing industry, techniques are known for the automatic and semiautomatic filling of various types of casings with viscous meat emulsion. In general, these techniques include positioning a shirred continuous film casing length over a stuffing horn and thereafter continuously deshirring the casing and stuffing the deshirred casing with viscous meat emulsion fed under pressure through the stuffing horn and into the casing interior. As used herein, the term casing or tubular casing is intended to mean tubing of natural or manufactured materials, and the term casing length" is intended to mean continuous tubular casing lengths.Shirred tubular casings are also known to persons familiar with the art as "sticks", such "sticks" being long lengths of casing having a substantially large bore, which have been shirred and compressed into short compact self-sustaining lengths, or which may be a package of shirred and compressed casing sheathed inside a retaining sleeve. Apparatus and processes are well known in the food casing art for producing shirred tubular cellulosic food casings such as, for example, the apparatus and processes disclosed in U.S. Patent Nos. 2,983,949 and 2,984,574 to Matecki. These apparatus may be employed in the preparation of pleated and compressed tubular casings wherein the compression ratios (unshirred to shirred stick length) are in the order of at least about 40:1 and up to about 100:1 or even greater.Using suitable food stuffing machinery, casing lengths can be stuffed and formed into unit size links of particulate or comminuted viscous materials, such as meat emulsions, or the like.

In the art of producing sausages and similar food products, the finely divided meat compositions commonly referred to as emulsions, are conventionally stuffed into the tubular casing materials of long length which, as stated above, may be of natural or manufactured materials. Large sausage products used in slicing for multislice package putup are usually made in casings which range in size from the trade designation #21/2 (73 mm. diameter) to #9 (129 mm.

diameter). In the production of large sausage products, a clip closed end casing of precut length is first manually sheathed over the end of a stuffing horn and then stuffed with a food emulsion. As the stuffing operation progresses, the clip closed end of the casing moves outward of the stuffing horn and the casing itself deshirrs and reattains its original length, or a length substantially close to its original length. The stuffed casing is then tied, twisted or clipped into predetermined unit length cylindrical packages.

The stuffed and encased food emulsion is subsequently cooked and cured according to one or the other of conventional processes, depending on the product being made, and may thereafter be and usually is sliced and packaged into units of predetermined weight and slice count for retail sale. The high speed slicing devices employed in such packaging operations are pre-set to yield a specific weight-by-slice count for use in obtaining unit packages of equal weight.

Therefore an important aspect of a commercially acceptable large sausage product is that the tubular finished processed sausage product have a substantially uniform diameter from end to end and in successive pieces of the same designated size. Moreover, the diameter of the slices must be uniformly precise in order to assure that the slices will fit into the preformed rigid packaging frequently used.

Since a large sausage casing stuffed with a food emulsion has two generally hemispherical, rounded ends, these rounded ends are generally not used in producing equal weight packages and are either discarded or reworked. Thus another aspect of importance commercially is to have a large sausage casing stuffed with uniform tight ends to thereby minimize the amount of end portion food product cut off from the uniformly cylindrical portion.

Years of commercial utilization of manufactured sausage casings such as prepared from unsupported or fibrous reinforced cellulose have provided the experience for determining optimum stuffing and processing conditions for various classes of sausage product. Sausage generally needs to be encased or stuffed to "green" or unprocessed diameters that have been selected on such experience and recommended for such optimum performance. In commercial practice, a recommended stuffing diameter for each size and type of casing has been established and tabulated in recommended operating procedures determined by the casing manufacturer for guidance of the sausage maker.

When a casing is understuffed from the recommended "green" diameter, the result generally is a processed product that is not uniform in diameter from end to end and from piece to piece; the product is undesirably wrinkled in appearance; and the processed sausage may have an emulsion breakdown yielding undesirable pockets of fat or liquid.

When a casing is overstuffed from the recommended "green" diameter, the casing may split or break apart at the stuffing station or subsequently, in transport to or in the cooking/smoking processing operations.

This results in a costly waste of emulsion and in the labor expense for cleanup.

For many years, the apparatus and methods employed to prepare such encased food products, particularly food products encased in large diameter casings, have relied largely if not exclusively on manual manipulation in controlling the stuffing of food emulsion into predetermined length sausage links or packages. Recently, advances in the art have resulted in the introduction of apparatus for machine control of the stuffing operation which have provided means for preparing uniformly sized encased products such as disclosed, for example, in U.S. Patents 2,871,508, 2,999,270, 3,264,679, 3,317,950, 3,454,980, 3,457,588, 3,553,769, 3,621,513 and 3,751,764. Of particular interest in this respect is applicants' copending (U.K. Patent) application No.

44988/76 (Serial No. 1565356 the disclo- sure of which is incorporated here by reference.

In the automatic sausage casing stuffing technique epitomized in the above-noted copending application No. 44988/76 (Serial No. 1565356) the technique is found to involve the combination of a sizing ring or disc arranged and disposed inside the casing being stuffed, coacting with an annular snubbing ring arranged and disposed exteriorly of the casing at a selectably variable distance along the casing length from the sizing ring. The sizing ring has an outer rim circumference greater than the inner circumference of the casing, and the annular snubbing ring has an inner passage circumference smaller than the outer circumference of the finished sausage product being made.Both the sizing disc and the snubbing ring are disposed in coaxial alignment with the stuffing horn of the sausage making machine, and provision is made to controllably vary the linear distance between the sizing disc and the snubbing ring.

By lessening this linear distance, the change in the path of casing moving from its stretched circumference as it deshirrs over the sizing disc, to its proscribed circumference as it passes through the space between the stuffing horn outer surface and the inner passage circumference of the snubbing ring, becomes more abrupt and increased frictional forces at the areas of casing contact with these control elements will increase a braking or holdback action on the casing.

Conversely, by increasing the linear distance between the sizing disc and the snubbing ring, the change in the path of the casing between these two casing contacting elements become less abrupt, effecting a decrease in frictional forces at the casing contact areas with a consequent decrease of braking or holdback action on the casing.

Now, it can be readily appreciated that for a given and reasonably closely maintained set of operating parameters, including type and condition of casing, consistency of the emulsion, emulsion pump speed and output pressure and, say the parts wear condition of the stuffing apparatus, an increased holdback force on the casing will tend to cause higher casing internal pressure and a larger product circumference, while decreased holdback force on the casing will lessen casing internal pressure and make for a smaller product circumference.

Since the desideratum is to maintain a constant product circumference, for the purposes and reasons hereinabove described, the linear distance between the sizing disc and the snubbing ring is controllably changed to compensate for variations and aberrations in the other aforedescribed operating parameters which are not so easily controlled.

Thus, prior to the present invention, the advance in the art which comprises the invention disclosed in the aforementioned U.K. Patent Application No. 44988/76 (Serial No. 1565356) comprehended the attainment of holdback control by controllably varying the distance between the sizing disc and the snubbing ring.

As development of the apparatus and method concepts disclosed in the aforesaid U.K. Patent Application No. 44988/76 (Serial No. 1565356) progressed, it became apparent that a greater degree of control and expansion of the range of the attainable product diameter was necessary, not towards making products of greater varying diameters, but towards providing greater compensating potential in the stuffing apparatus to accommodate the uncertainties attending variations in casing compositions and materials, variations in meat emulsion, and variations in other operating parameters. Viewed from the position of engineering development, this constituted a goal to provide a capability to understuff and/or to overstuff the casing being filled in any given stuffing operation to an extent greater than heretofore possible and with enhanced control and precision.It was further apparent to and substantiated by the developers that while increasing the sizing disc diameter increased the casing holdback and could provide some degree of increment at the overstuffing end of the controlled range, such step not only did nothing for the understuffing end of the range, but if carried too far, it could stretch the casing to an extent so far greater than the diameter of the finished sausage product, that the casing material elastic limit would be exceeded, or the casing otherwise detrimentally affected.

If an undersized diameter sizing disc was used in an effort to increment the understuffing end of the range, the results would be different but equally undesirable since the casing would not be stretched enough to provide uniform stretch-sizing to enable attainment of a precisely uniform stuffed product diameter.

With this then being the state of the art, the present invention was conceived and developed to provide a greater than heretofore attainable degree of control and range between overstuffed diameters and understuffed diameters in food casing stuffing operations.

The invention also seeks to provide greatly increased capability to adjust for, compensate, and correct a greater than heretofore possible number and variety of operational swings, parameter variations, maladjustments, and apparatus parts wear in food casing stuffing operations.

According to a first aspect of the present invention there is provided a method of sizing control in food casing stuffing in which method the casing being stuffed is first expanded by interior circumferential contact, and then contracted by exterior circumferential contact, the circumferential contact being maintained circumferentially uninterrupted, and the width of the interior circumferential contact area being maintained at from 0.05 to 1.0 times the interior diameter of the casing at the area of interior circumferential contact.

Preferably the outer circumferential rim width of the sizing disc is in the order of from about 0.15 to about 0.5 times the overall diameter of the disc.

According to a second aspect of the present invention there is provided an apparatus for food casing stuffing which comprises a food casing stuffing sizing disc having a circumference greater than the interior circumference of a food casing within which it is to be used, and a circumferential rim width of from 0.05 to 1.0 times the overall diameter of the disc, means downstream of said sizing disc, for contracting said casing by exterior circumferential contract and means downstream of said contracting means for stuffing the food casing.

Preferably the width of circumferential contact area is maintained at from 0.15 to 0.5 times the interior diameter of the casing at the area of interior circumferential contact.

The invention will hereinafter be further described by way of example with reference to the accompanying drawings in which: Figure 1 is a side elevation schematic view showing apparatus according to the second aspect of the present invention in place on a stuffing apparatus in cooperative arrangement with other stuffing apparatus elements, and Figures 2 to 5 are respective sectional representations of alternative embodiments of sizing discs of apparatus in accordance with the second aspect of the present invention.

Figure 1 of the drawing shows a section of a length of food casing 11 in place on the stuffing horn 13 of a casing filling machine.

Only those parts of the casing filling machine essential to an understanding of this invention are shown in the drawing. The casing 11 is shown shirred at the right in the drawing and undergoing deshirring and filling as it passes from right to left to its ultimate filled condition shown in drawing Figure 1 at the left.

A sizing disc 15 is disposed concentrically on the stuffing horn 13 interiorly of the casing 11, with its outer circumferential rim 17 in slideable contact with the inner circumferential surface of the casing 11 adjacent the shirred portion of casing at the right in Figure 1 of the drawing.

An annular snubbing ring 19 having an inner passage 21 circumference smaller than the outer circumference of the finished sausage product being made is arranged and disposed concentrically on the stuffing horn 13 adjacent the end thereof as shown in the drawing. In the illustrated embodiment, the snubbing ring 19 fulfills a second function which is to serve as a sealing ring to hold the casing snugly against the stuffing horn outer surface and thereby prevent emulsion backflow into the as yet unfilled zones in the deshirring casing. It should be noted that the sizing discs according to this invention may be used with equally advantageous results with other forms of snubbing rings. It is not essential. for instance, that the inner passage 21 of the snubbing ring be so small as to define a casing to stuffing horn sealing relationship.It is necessary only that the snubbing ring inner passage 21 be small enough to effect the degree of contraction of the casing necessary to the range of sizing control desired.

As sausage product emulsion 23 under pressure from an emulsion pump means, not shown; feeds into the casing 11 from the stuffing horn 13, the casing fills to the condition shown at the left in Figure 1 of the drawing. The casing 11 is continuously drawn from its shirred condition shown at the right in Figure 1. over the rim 17 of sizing disc 15. and then circumferentially proscribed and infolded through passage 21 of the snubbing ring 19.A combination of the adjustment of the distance X shown in the drawing Figure 1, the diameter D of the sizing disc. and the ratio of the sizing disc rim width W to the sizing disc diameter D, W/D. determines the extent of the braking or holdback force on the casing length as it stretchedly advances over the rim 17 of sizing disc 15. is then infolded through passage 21 of snubbing ring 19, and ultimately progresses to its fully stuffed condition. When the distance X is increased, as explained hereinabove, there is a lessening of the casing braking or holdback action and the casing will tend to be understuffed, while a decrease in the X distance will tend to effect casing overstuffing.

In the course of the development of this invention, operating experience indicated that a desirable objective would be the attainment of capability to overstuff the product being made to a diameter increment of 0.010", and to understuff the product to a 0.06" diameter decrement respectively over and under the industry recommended stuffed diameter. It was found, as discussed hereinabove, that increasing or decreasing the sizing disc diameter D, could not in and of itself accomplish this. It was further found that the fullest practically attainble variation in the distance X between the sizing disc 15 and the snubbing ring 19, similarly could not accomplish the sought goal, nor could the combination of these variable parameters. It was then projected that increasing the widths of the rim surfaces of the sizing discs would produce the desired results.

Experimental work included the testing of assorted sizing disc sizes of from 1.5 inches (3.81 cm) to 5.0 inches (12.7 cm) diameter.

For each sizing disc size tested, sample discs were made having 1/8 inch (.32 cm), 1/4 inch (0.64 cm), 1/2 inch (1.27 cm), 3/4 inch (1.91 cm), 1 inch (2.54 cm), 1-1/2 inch (3.81 cm) and 3 inch (7.62 cm) rim widths.

Tests led to the conclusion that sizing discs with rim widths of less than 1/4 inch (0.64 cm) and greater than 1-1/2 inches (3.81 cm) were not useful in attaining the sought goal, but that discernible stuffing range increments resulted with all tested sizing disc diameters when the rim widths were from 1/4 inch (0.64 cm) to 1 inch (2.54 cm).

The tests also showed that for all tested sizing disc diameters, the rim width most effective in producing the desired results was 3/4 inch (1.91 cm).

From the data thus compiled the range of rim widths W to diameter of sizing discs D, W/D, is calculated. The low end of the range, W/D = 0.05, is computed by dividing the narrowest rim width, 0.25 inch (0.64 cm) by the largest considered sizing disc diameter 5 inches (12.7 cm), and the high end of the range W/D = 1.0 is computed by dividing the widest rim width, 1-1/2 inches (3.81 cm) by the smallest considered sizing disc diameter, 1-1/2 inches (3.81 cm).

Similarly the somewhat narrower and preferred range is calculated by dividing the most effective sizing disc rim width, W = 3/4 inch (1.91 cm), by the largest considered sizing disc diameter, D = 5 inches (12.7 cm) to obtain 0.15, the low end of the range, and then by the smallest considered sizing disc diameter, D = 1-1/2 inches (3.81 cm) to obtain 0.5, the high end of the preferrred range.

The sizing disc 15 shown in Figure 1 of the drawing is cup-like in form. Other forms of sizing discs according to the invention are shown in Figures 2-5 of the drawing. Figure 2 shows a solid annulus form. Figure 3.

allows a reversed version of the disc 15 of Figure 1. Figure 4 shows a sizing disc with a T-shaped cross section, and Figure 5 shows a modified T-shaped cross section sizing disc. All of these illustrated embodiments and others not illustrated are within the scope of this invention as long as the criteria of the disc rim width to disc diameter relationships are met.

The materials of construction for fabricating sizing discs according to the inveniton have been found most suitably to be polyethylene, styrene, and stainless steel, and these, while not essential to the practice of the invention in a broad sense, are considered the preferred materials based on experimental testing and experience.

The sizing discs according to the invention will work well in combination with certain alternative apparatus arrangements in addition to the one described hereinabove, including those systems which include snubbing rings with relatively large clearance passages 21 around the stuffing horn. Sizing discs according to the invention, particularly those shaped to have a rim edge protruding in the direction of the progression of the casing as it is filled, work with particularly great advantage in conjunction with the improved food casing stuffing sizing control apparatus and method invention which is the subject of our copending application No. 20119/77 filed concurrently with this application.

WHAT WE CLAIM IS: 1. A method of sizing control in food casing stuffing in which method the casing being stuffed is first expanded by interior circumferential contact and then contracted by exterior circumferential contact, the circumferential contact being maintained circumferentially uninterrupted, and the width of the interior circumferential contact area being maintained at from 0.05 to 1.0 times the interior diameter of the casing at the area of interior circumferential contact.

2. A method as claimed in claim 1 in which the width of the circumferential contact area is maintained at from about 0.15 to about 0.5 times the interior diameter of the casing at the area of interior circumferential contact.

3. Apparatus for food casing stuffing which comprises a food casing stuffing sizing disc having a circumference greater than the interior circumference of a food casing within which it is to be used, and a circumferential rim width of from 0.05 to 1.0 times the overall diameter of the disc, means downstream of said sizing disc, for contracting said casing by exterior circumferential contract and means downstream of said contracting means for stuffing the food casing.

4. Apparatus as claimed in claim 3 in which the rim width is from 0.15 to 0.5 times the overall diameter of the disc.

5. Apparatus as claimed in claim 3 or 4 in which the material of which the sizing disc is fabricated at least in part from polyethylene or styrene or stainless steel.

6. Apparatus as claimed in any of claims 3 to 5 further comprising a stuffing element over which a shirred food casing may be mounted, the sizing disc being disposed interiorly of the casing with the outer circumferential rim surface contracting the inner surface of the casing as it deshirrs in the course of the stuffing operation.

7. A method of sizing control in food casing stuffing substantially as hereinbefore particularly described with reference to the accompanying drawings.

8. Apparatus for sizing control in food casing stuffing substantially as hereinbefore particularly described with reference to and as illustrated in Figure 1, 2, 3, 4 or 5 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (8)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   diameter, D = 1-1/2 inches (3.81 cm) to obtain 0.5, the high end of the preferrred range.

   The sizing disc 15 shown in Figure 1 of the drawing is cup-like in form. Other forms of sizing discs according to the invention are shown in Figures 2-5 of the drawing. Figure 2 shows a solid annulus form. Figure 3.

   allows a reversed version of the disc 15 of Figure 1. Figure 4 shows a sizing disc with a T-shaped cross section, and Figure 5 shows a modified T-shaped cross section sizing disc. All of these illustrated embodiments and others not illustrated are within the scope of this invention as long as the criteria of the disc rim width to disc diameter relationships are met.

   The materials of construction for fabricating sizing discs according to the inveniton have been found most suitably to be polyethylene, styrene, and stainless steel, and these, while not essential to the practice of the invention in a broad sense, are considered the preferred materials based on experimental testing and experience.

   The sizing discs according to the invention will work well in combination with certain alternative apparatus arrangements in addition to the one described hereinabove, including those systems which include snubbing rings with relatively large clearance passages 21 around the stuffing horn. Sizing discs according to the invention, particularly those shaped to have a rim edge protruding in the direction of the progression of the casing as it is filled, work with particularly great advantage in conjunction with the improved food casing stuffing sizing control apparatus and method invention which is the subject of our copending application No. 20119/77 filed concurrently with this application.

   WHAT WE CLAIM IS: 1. A method of sizing control in food casing stuffing in which method the casing being stuffed is first expanded by interior circumferential contact and then contracted by exterior circumferential contact, the circumferential contact being maintained circumferentially uninterrupted, and the width of the interior circumferential contact area being maintained at from 0.05 to 1.0 times the interior diameter of the casing at the area of interior circumferential contact.
2. 2. A method as claimed in claim 1 in which the width of the circumferential contact area is maintained at from about 0.15 to about 0.5 times the interior diameter of the casing at the area of interior circumferential contact.
3. 3. Apparatus for food casing stuffing which comprises a food casing stuffing sizing disc having a circumference greater than the interior circumference of a food casing within which it is to be used, and a circumferential rim width of from 0.05 to 1.0 times the overall diameter of the disc, means downstream of said sizing disc, for contracting said casing by exterior circumferential contract and means downstream of said contracting means for stuffing the food casing.
4. 4. Apparatus as claimed in claim 3 in which the rim width is from 0.15 to 0.5 times the overall diameter of the disc.
5. 5. Apparatus as claimed in claim 3 or 4 in which the material of which the sizing disc is fabricated at least in part from polyethylene or styrene or stainless steel.
6. 6. Apparatus as claimed in any of claims 3 to 5 further comprising a stuffing element over which a shirred food casing may be mounted, the sizing disc being disposed interiorly of the casing with the outer circumferential rim surface contracting the inner surface of the casing as it deshirrs in the course of the stuffing operation.
7. 7. A method of sizing control in food casing stuffing substantially as hereinbefore particularly described with reference to the accompanying drawings.
8. 8. Apparatus for sizing control in food casing stuffing substantially as hereinbefore particularly described with reference to and as illustrated in Figure 1, 2, 3, 4 or 5 of the accompanying drawings.