CA2089513C - Dog food in the shape of a bone and a process for its production - Google Patents

Abstract

A strand consisting of an external envelope based on cereals and an internal filling is formed by cooking/co-extrusion. While the external envelope is still thermo-plastic, the strand is coat and moulded to form the bone.
A food for dogs in the shape of a bone consisting of an external envelope 1 based on cereals and an internal filling 2 is obtained in this way.

Description

~~89~~.3 This invention relates to a food for dogs in the shape o~ a bone and to a process for the production of this food.
The predilection of dogs for bones is well known. In addition, a food for dogs has to satisfy certain nutrition al requirements.
Various attempts have been made to provide food for dogs to satisfy this dual requirement of shape and composi-tion.
US-PS 3,567,459 describes a process for the production by extrusion of foods for dogs resembling bones in which a thermoplastic mass in the form of a flavoured edible paste is extruded in the form of a cylindrical strand which is then transformed by an unspecified technique into a food in the shape of a bone.
This document, which is confined to the production of a product having the external shape of a bone made from a flavoured edible paste, does not provide for the production of a product having the appearance of a bone while satisfy-ing the requirements in regard to nutritional qualities.
This is because, since the extruded product has to be thermoplastic, the paste from which it is formed cannot at the same time readily satisfy nutritional requirements in regard to composition which conflict with this thermoplas-tic character, Tn addition, a.t is known that it is impos-Bible to extrude a paste having a fats content of more than a few percent.
Now, it has been found that a food for dogs in the shape of a bane consisting of an external anveloge based on cereals and an internal filling of any kind enables the dual requirement of shape aind nutritional qualities to be satisfied, the shape being obtained by ~rirtue of the thermoplastic properties of the envelope and the nutrition-al qualities resulting from the filling. In addition, since this product has a crispy texture on the outside and a marrowy texture on the inside, it is in itself much more appetizing for the dog than a bone extruded in accordance with the prior art.
Accordingly, the present invention relates to a food far dogs in the shape of a bone consisting of an external envelope of edible paste and an internal filling of any kind.
Tt has also be found that this product can be obtained by cooking/co-extrusion under certain conditions.
In the context of the invention, cooking/co-extrusion is understood to be a process of the kind described, for example, in US-PS 3,480,445, in which an external envelope is extruded under pressure with a small addition of water.
During this step, the water is evaporated and the envelope is cooked, the cooked product expanding as it leaves the extrusion die. At the same time, a filling of any kind is co-extruded inside the envelope. According to the prior art, the product is then canventionally cooled and cut into pieces.
EP 178 878 describes a device for cutting a strand consisting of an external envelope of an edible paste and an internal filling of any kind. According to this docu meet, a conveyor belt transports the strand, at least one knife being arranged above the conveyor belt. The knife makes a reciprocating downward movement combined with a longitudinal movement in the direction of advance of the product to be cut. On the one hand,. however, this document does not relate to a cooked product and, cm the other hand, only enables a strand to be cut perpendicularly of its axis.
Now, co-extruded cooked products cannot be compared with products obtained by simple co-ektrusion which then have to be cooked to give a finished product. This is because uncooked products are highly deformable: Thus, compression of the fi7Lling which inevitably accompanies 35. cutting merely results in stretching of the envelope which 2~~9513 enables the compressed filling to assume the necessary position. By cantrast, products obtained by cooking/co-extrusion lead directly to a finished product. Thus, the plastic character of a product obtained by such a process is very limited and compression of the filling caused by a knife cannot be completely compensated by stretching of the envelope which can only ever be minimal.
Finally, the prior art does not enable products of any shape to be produced from a co-extruded strand.
Accordingly, the object of the present invention was to solve these problems by making it possible to produce a food for dogs in the shape of a bone obtained by cooking/
co-extrusion and consisting of an external envelope of edible paste and an internal filling.
Accordingly, the present invention relates to a process for the production of a food for dogs in the shape of a bone in which a strand consisting of an external envelope of edible paste based on cereals and an internal filling is produced by cooking/co-extrusion and, while the envelope is still thermoplastic, the strand is cut longi--tudinally in such a way that the cutting tool does not enter the filling, the strand also being cut into segments perpendicularly of its length and simultaneously moulded.
By virtue of this particular form of cutting, in which the cutting tool does not enter the falling during the longitudinal cutting of the strand, but only during the perpendicular cutting into segments to form the individual bones, minimum compression is appiied to the filling which thus stays inside i.ts envelope without a tendency to flow 3~ put therefrom.
Other features and advantages will become apparent from the following description'in conjunction with the accompanying drawings provided purely by way of example, wherein:
Figure 1 is a diagrammatic partial section through a 2~~~~~3 bane according to the invention.
Figure 2 is a perspective view in a section of a cooked/co-extruded strand before cutting.
Figure 3 is a diagrammatic view of an arrangement for carrying out the process according to the invention.
Figure 4 shows part of the arrangement illustrated in Fig. 3.
Figure 5 is a diagrammatic view illustrating the cutting line of a co-extruded strand.
As shown in Fig. 1, a bone according to the invention consists of an external envelope 1 of an edible cereal-based paste and an internal filling 2. This bone is in the shape of a long bone, i:e. it consists of a tubular body corresponding to the diaphysis of a real bone and has a head at either end corresponding to the epiphyses of an actual bone.
The process for making this product essentially com-prises forming a strand consisting of an external envelope based on cereals and an internal filling by cooking/co-extrusion. While the external envelope is still thermo-plastic, the strand is cut and moulded to form the bone.
Since the thermoplastic properties last for only a few seconds after leaving the cooking/co-extrusion arrangement, the cutting operation has to take place in a short time.
Thus, in contrast to the prior art, cutting is carried out before cooling of the product axed not afterwards.
One example of a thermoplastic composition for an external envelope is a mixture of wheat,flour, sugar and salt, for example in the following ratios by weight: flour 89%, sugar 10% and salt 1%. Water is added to this mixture in a quantity of 5 to 20%. This' is because it has been found that, under typical cooking/co-extrusian conditions, i.e. a pressure of approximately 100 bar and a temperature of the order of 150°C, the addition of water represents a good compromise between expansion on leaving the extrusion 20~~~~.3 die and the thermoplastic character.
The filling may consist of a mixture of 70% by weight fats, 20% by weight fibers, such as mixture of flour and bran, and 10o sugar. Another compasition may consist, for 5 example, of a mixture of 43% by weight fats, 33% sugar, 15%
fibres, ~% meat and 3% various additives.
In a principal embodiment of the invention, the strand does not have a circular cross-section on leaving the cooking/co-extrusion arrangement. Tnstead, as illustrated in Fig. 2, the strand consists of an external envelope 1 having a central body 3 of circular or elliptical cross section and two lateral appendages radially opposite one another relative to the central body 3. Thus, the external envelope 1 consists of a central body 3 and two lateral ribs 4, the central body 3 containing the filling 2.
Finally, the strand is cut and moulded into segments in the shape of a bane. To this end, the strand is cut longitudinally at its sides in zones where there is no filling to give the profile of a bone by forming the tubular body and the two heads. The strand is also cut perpendicularly of its length to form segments moulded into the shape of a bone.
In cases where 'the extruded strand has the shape illustrated in Fig. 2, the strand is cut longitudinally along its ribs 4. In cases where the extruded strand has a circular or elliptical cross-section, fox example as a result of preliminary flattening, longitudinal cutting is carried out along the sides of the strand without the cutting tool entering the filling. Accordingly, it is useful in this case to have an envelope of adequate thick-ness.
The process according to the invention is carried out using the arrangement illustrated in Fig. 3. This arrange-menu comprises a cooking/co-extrusion unit 5, for example of the type described in US-p8 3,480,445, and a cutting 20~~~~3 unit 6 fox cutting the strand obtained. A device 7 for flattening the strand, consisting for example of a cylinder rotatable about its horizontal axis and perpendicular to the direction of advance of the strand, may be arranged between the cooking/co-extrusion unit 5 arid the cutting unit 6. A conveyor belt 8 may be provided to transport the strand from the cooking/co-extrusion unit 5 to the cutting unit 6.
The cutting unit 6 consists of two vertically adjacent cylinders 9 and l0 with parallel horizontal axes perpen-dicular to the direction of advance of the conveyor belt 8.
As illustrated in Fig. 4, the upper cylinder 9 is provided at regular intervals in its outer surface with recessed female impressions 11 of a profile corresponding to the shape of the end product, i.e. consisting of a narrow central part and two widened ends radially spaced from one another and separated by a surface 12 which may be part of a cylinder, each female impression 11 being delimi-ted by an edge line 13 formed by the intersection of the surface 12 and the impression 11. Each female impression 11 has one or more orifices 111 connected to a source of gas under pressure (not shown).
The lower cylinder 10 is provided at regular intervals on its outer surface with projecting male impressions 14 spaced radially from one another and separated by a reces sed surface 15. In the same way as each female impression 11, each male impression 14 has an edge line 16. This edge line 16 is of a profile corresponding to the edge line 13 of the opposite female impression 11, the male impression preferably penetrating slightly intp the female impression.
The two cylinders 9 and 10 are positioned relative to one another in such a way that a male impression always faces a female impression, their respective edge lines thus being in contact.
The mode of operation of the arrangement used to carry 2~~~~~~
out the process according to the invention is described in the following.
A strand consisting of a thermoplastic external envelope and a filling is produced by the cooking/co extrusion unit 5. While it is still thermoplastic, this strand - optionally after having been flattened - is trans-ported to the cutting unit by the conveyor belt.
The strand is then cut by stamping between a male impression and a female impression. Since longitudinal cutting of the strand takes place without the shear line formed by the two edge nines entering the filling, the filling is unablevto flow out from the strand. The cutting of the strand into segments, which is carried out perpen-dicularly, produces a buttonhole in the outer envelope because the shear line enters the filling. However, this buttonhole has a very limited opening so that none of the filling escapes from the envelope.
In Fig. 5, the cutting lines - both longitudinal and perpendicular - are shown in the form of dotted lines,wthe longitudinal cutting,lines being denoted by the reference L and the perpendicular cutting lines being denoted by the reference P.
At the same time as the strand is being compressed between the female and male impressions, its outer surface formed by the thermoplastic envelope l assumes the form of those impressions so that the envelope is moulded into the shape of a bone. More particularly, the filling undergoes slight compression during perpendicular cutting which tends to deform the external thermoplastic envelope at the twos ends of the segment formed so that the envelope is applied to the male and female impressions: Thus, even if the strand has two lateral ribs at tha beginning, these two ribs disappear when the two heads'of the bone are formed.
In addition, as can be seen from Fig. 1, the filling tends to expand radially during perpendicular cutting, thus 20~~~13 producing a filling which is wider at the heads of the final bone than in the tubular body of the bone.
It is possible in the manner described above to obtain a food for dogs in the shape of a bone of which the nutri tional qualities may be modified as required in dependence upon the composition of the filling and which has a crispy external envelope and a marrowy internal filling.
The cylinders 9 and 10 continue to rotate and the male and female impressions separate while the waste produced by cutting is removed. The end product, still held in the female impression, is then ejected by the injection of compressed air through the orifices 111. In addition, ejection by the injection of compressed air has the advan-tage; through the cooling effect which it produces, of fixing the shape of the product which thus loses any thermoplastic character.

Claims (4)

1. A food for dogs having the shape of a bone consisting of an external envelope formed of an edible cereal-based paste, and an internal filling;
said food being formed by cooking and co-extruding the envelope and the filling to form a strand; cutting the strand longitudinally with a cutting tool while the envelope is still thermoplastic, wherein the cutting tool does not enter the filling;
cutting the strand into segments perpendicular of its length; and simultaneously moulding the segments.

2. A process for the production of a food for dogs in the shape of a bone, in which a strand consisting of an external envelope of an edible paste based on cereals and an internal filling is produced by cooking/co-extrusion and, while the: envelope is still thermoplastic, the strand is cut longitudinally with a cutting tool in such a way that the cutting tool does not enter the filling, the strand also being cut into segments perpendicularly of its length and simultaneously moulded.

3. A process as claimed in claim 2, in which the strand consists of an external envelope comprising a central body and two lateral ribs, the central. body containing the filling.

4. A process as claimed in claim 3, in which longitudinal cutting is carried out in the lateral ribs.