METHOD FOR SCALING FRESH FISH AND REMOVING ITS INTERNAL ORGANS AND DEVICE FOR IMPLEMENTATION OF THE OFFERED METHOD

Abstract: Method and device for scaling fish and removing its internal organs by continuously advancing the fish along a treatment path while simultaneously exposing the fish body to high-pressure water jets (26). During treatment the fish is positioned vertically, with its belly downwards. The forces (14, 46, 48) required for holding and transporting the fish are applied laterally to the upper part of the fish body, which is harder, without however touching the belly area, which is soft and therefore is left free. Descaled fish proceeds to a position for cutting the belly area and removing internal organs. The treatment is carried out in the same device, efficiently and without deterioration of gustatory properties.

Description: Method for scaling fresh Ωsh and removing its internal organs and device for implementation of the offered method Field of the invention The proposed invention is pertinent to the technology and equipment for the treatment of fresh fish and can be applied for example in various branches offish industry, in marketing, in public catering etc. Background of the invention To the present day a technology and, consequently, a machine is not available that would allow to combine together the process of high-quality scaling of fish and the process of removing its internal organs, to bring these processes together in time, and thus create possibility of combining these two usually separate operations into a single one, which could substantially improve consumer qualities of goods. The present invention offers a new method for fish scaling and removal of internal organs, as well as a machine for its implementation and its main object is elimination of the above-indicated deficiency. There are known in the art various methods and devices for fish scaling and for the removal of internal organs. However these methods and devices are mostly devised to perform the above operations in separate and on separate machines and by different methods. For example, it is well known to use for scaling the brushes made from various materials and rotating at different angles to the fish surface (USA patents Nos. 5197916, 5184973. This method can be implemented with relative success for scaling frozen fish. When, however it is required to scale fresh fish, this method can damage the skin. Furthermore it can damage thin and fine tissues of abdominal cavity and rupture or badly traumatize internal organs. All this is associated with worsening the gustatory properties. Therefore, for scaling fresh fish the above method is not suitable if it is required to preserve gustatory properties. In order to improve the fish scaling quality, a method of scaling has been devised in which a compressed air jet is employed. This method is disclosed in Japanese patent No. JP6339336. Unfortunately this method is only of limited use, because it requires powerful compressors, which employs the most expensive type of energy i.e. compressed air and therefore this method is unavoidably is expensive. There are known other inventions offering to use water jets under high pressure for scaling fish. So, for example, Japanese patent No.4228023 offers to remove scale by means of water jets supplied through elongated rectilinear slits with their length exceeding the maximum width of the treated fish. In order to maintain gustatory properties the patent suggests removing entrails in advance, on a separate machine, since the existing methods and devices for a conveyer transportation offish in the course of scaling do not provide for safety of fish internal organs. Thus in order to carry out the scaling properly more than one operation and more than one machine is required. Nevertheless the method and device disclosed in this Japanese patent No.4228023 applying water jets under high pressure as a tool for scaling is the closest to our invention, since it can offer the highest quality of treatment. However, the method disclosed in Japanese '023 patent indicated above does not use all the advantages of the fish scaling by water jets. For example, this method employs such a sequence of operations, which does not provide for a satisfactory quality of scaling. Firstly, the Japanese device anticipates removing entrails prior to scaling. In this case it is practically impossible the clean the cut fish belly with a water jet, due to loss of elasticity and resistivity of the body tissue. Secondly, the elongated rectilinear nozzle shape employed in this method also will not provide for scaling quality because various parts of the fish body require dissimilar modes of operation with water jets (different angles of jet inclination, different distances from the nozzle to the surface to be treated etc.). Under the conditions when a jet supplied from a single nozzle treats the entire fish width, it is not possible to provide for a reliable and high-quality scaling of all portions of the fish body. Thirdly, the method of fixation and transportation the fish in the course of treatment as suggested in the '023 patent does not allow to protect the fish belly from being squeezed by the transportation elements and thus cannot guarantee preserving of gustatory properties. Therefore the method disclosed in '023 patent would be unavoidably forced to offer to scale the entrails separately. But not only '023 patent fails to suggest satisfactory method of fixation and transportation of the fish. Not even one out of the considered patents solves this problem. Basically, the fish is secured and moved either flat wise (patents of USA Nos. 5628680, 5197916, patents of Japan JP 4228023, JP 4837898) or on its back, with belly upwards (patents of USA Nos. 4091506, 4837898). Since the width of the transportation mechanism is kept constant and is not designed to accommodate the fish width, it might happen that the fish belly is over squeezed during transportation. For example, if the fish is moving flat wise, then in case there is some fish of small width, the holding and transportation elements over squeeze the belly. This is associated with damaging or destroying those entrails and deteriorating the gustatory properties. The same happens in those cases when the fish is held and transported with its belly up and is based on its back. Thus, despite there are known methods and devices for fish scaling, which employ high- pressure water jets, nevertheless they have very essential drawbacks noted above. Consequently, we can draw the conclusion that for the time being no method or machine are available where the fish scaling and removal of its entrails could be performed together, in a single operation, using water jets and without deteriorating the gustatory properties. Since no method of reliable, qualitative and efficient fish scaling is known, the removal of the viscera is performed on separate machines and devices, and very often it is carried out in combination with using high pressure water jets (patents of USA Nos. 4837898, 4535509, WO 9812929). This separate operation is performed prior to the fish scaling and very often they are even left to be done by the customer. Objects and summary of the invention The offered method of scaling fresh fish by means of the high pressure water jets is free from the above listed drawbacks, and allows to create a high-quality treatment technology and machine for fish scaling and entrails removal. Distinctive features and essence of the proposed method comprise the following: a) Fish scaling and removal of internal organs from abdominal cavity using high-pressure water jets is performed by positioning the fish vertically, with the belly downwards. The forces, required for holding and transporting the fish are applied strictly to the upper part of fish body, which is harder, without however touching the belly area, which is soft and therefore is left free. The above approach is implemented as follows: prior to the treatment the fish is positioned vertically and the lower surface of its belly is put on some reference plane A (see Fig. l). The means for fixation the fish and its transportation are located at some distance HI above the reference plane. This distance is selected to ensure, that even the belly area of the fish having maximum width (H2=max.) would not touch the fixation means. In this case this condition is also met for smaller fish. Positioning of the fish as explained above allows to avoid traumatizing the viscera during scaling and thus to preserve the gustatory properties irrespective of the fish size. b) The most rational sequence of steps is offered: in the beginning, the whole fish surface is scaled and only then the belly is cut and its internal organs are removed including kidneys (the so called "blood spots"). By virtue of this sequence of steps, the quality of the abdomen cavity scaling is improved as compared with the known methods when the fish is supplied for scaling in disemboweled condition. Since after disembowelment, the belly tissues lose elastic properties this area practically is not susceptible to scaling. c) The scaling is done throughout the whole width of the fish in sequence, by separate zones (selectively). This distinctive feature of the method takes into consideration the fact that various zones of the fish surface have different size of scale and is defined by different adhesion of the scales to skin. Therefore the offered method provides for the treatment of various sections of the fish surface by means of directing the water jet through the nozzles located at different inclinations to the fish body surface and residing at various distances from the treated surface sections. The geometry of the nozzle is selected to provide for a fiat fan-shaped jet. By virtue of this provision, the quality offish scaling substantially improves in comparison with the known in the art methods. d) After scaling, the fish is advanced to the position for removing viscera. The fish is positioned here in such a way, that the longitudinal plane of the fish body is aligned with the cutting disc (see Fig.2a). The upper part of the cutting disc always protrudes at a preset distance h from base surface A of the transportation system (Fig. 2a,b). By virtue of the above described positioning procedure, which is carried out before removing viscera the cleaning quality is significantly improved since the cutting disc is set up with respect to the fish body to cut the required part of the body irrespective of the body thickness. The disc is set up in such a manner, that on the one hand, under no circumstances the cutting edge should damage those fish organs which could cause change the gustatory properties and, on the other hand, would provide the mandatory cutting of the fish anus where a part of the viscera is held. Besides, the cleaning quality of the internal abdominal cavity is even more improved since cutting with the belly being downwards facilitates removal of the entrails, which easily fall down due to gravitation force. The quality of washing of the abdominal cavity is improved, since the probability for retention of removed organs and dirty liquid in the internal cavity significantly decreases. On the basis of the above explained distinctive features and advantages a new method for scaling fresh fish and removing its internal organs as well a machine for its implementation are offered. Brief description of the drawings The present invention will now be described in detail with references to the drawings. Fig.l . Schematic representation explaining positioning of fish to be cleaned according to the present invention. Fig.2a, b. Schematic representation explaining displacement of fish in the position of cutting the belly. Fig. 2c. Isometric representation of the proposed apparatus for the fish scaling and removal of internal organs. Fig.3a, b. Side and front views of the device represented in Fig.2c. Fig.4a. Partial enlarged side view of treatment path for the fish scaling. Fig.4b. Schematic top view of the treatment path for the fish scaling. Fig.4c. Cross-Sectional views of positions I, II,III,IV of Fig.4b. Fig.4d. Representation of the nozzle for supplying water jet to be used in the proposed apparatus. Fig.4e. Side view of the area for cutting the belly. Fig.4f. Top view of the area for cutting the belly. Fig. 4g. Cross-section 1 - 1 of Fig.4f. Fig.5. Enlarged representation of the proposed device front view. Detailed description of the preferred embodiments With reference to Figs.2c,3a, 3b, the proposed apparatus or machine 10 for scaling wish and removing its viscera comprises the following main components: a frame 12 on which a belt conveyer 14 with appropriate drive 16, is mounted, a receiving tray 18 with a bottom 20, a drive 22 of high pressure pump 24 creating water jets, which are delivered through nozzles 26, a machine cover 28, appropriate piping system 30 for drainage and removal of wastes, a cutting means 32 for cutting the fish belly to enable entrails removal, a console with control system 34 for operating the machine, a spring means 36 for maintaining required distance between guiding rollers 38 of the belt conveyor. The machine operates in the following way: the fish is manually (or from an automatic loader) fed on the receiving tray. The fish is supplied is succession, one by one. As best seen in Fig. l the fish is positioned vertically on the bottom of the receiving tray, i.e. its belly facing downwards and its head forward. The fish is advanced by conveyor along the upper plane of the machine frame. This plane will be referred to further as a treatment path and its level is designated in Figs.1,2 by numeral A. This level is the same as of the bottom of the receiving tray. Belts of conveyer 14, which is driven by drive 16, transport the fish. High-pressure pump 24 is driven by drive 22 to provide for high pressure of about 14-16 bars, sufficient to supply water jets through nozzles 26 mounted in various areas along the treatment path. Cover 28 provides for reliable protection of an operator from splashing and piping system 30 allows removing waste materials from the treatment path. The belts of the conveyer are arranged at both sides of the fish to support the fish laterally, the belts are arranged to touch the fish body substantially in the upper part thereof, since the tissues in this part are relatively hard. With reference to Fig.4a,4b it is seen that conveyor 14 comprises left branch L and right branch R. Each branch consists of three parallel belts, residing one on another. The belts are directed by plurality of guiding rollers 38, which are arranged in such a manner that only one side of the fish body is in contact with the corresponding branch, while the opposite side of the fish body is exposed to water jets, emerging from nozzles 26 and cleaning the fish from scale. The fish advances along the treatment path and water jets successively treat its lateral sides. The treatment path comprises successive discrete positions I, II, III, IV, which are shown in Fig.4b. Referring now to Figs.4a, 4c it is seen, that belts of each branch are arranged in such a manner that when the fish moves, the middle zone B is left open between upper and lower conveyor belts. This zone is exposed to water treatment by jets emerging from nozzles located at one side of the fish. From the opposite side there are left two zones exposed: C and D (the upper and lower zone). The above mentioned can be illustrated by Figs. 4b and 4c, in which it is seen that in working position I the upper and lower belts of the left branch do not touch the left side of the fish body (motion-wise) since they are guided by common roller 381, located remote from the fish body. The middle belt of the left branch is guided by roller 382, which is located close to the fish to ensure that the middle belt touches left side of the fish body. Common roller 383, situated at the opposite side is located close to the fish body and all three belts touch the right side of the fish. In the free space available between the fish and the upper and lower belt of the left branch reside nozzles 261u and 261b, which direct high-pressure water jet correspondingly to the left top and to the left bottom zones C, D of the fish body. The left middle part of the fish body is not treated so far, since it is contact with middle belt, guided by roller 382. It can be appreciated that left side of the fish is in contact either with one or two belts of the left branch, while the opposite side is always in contact with three belts of the right branch. By virtue of this provision fish is advanced by conveyor along the treatment path. Spring means 36 keeps the distance between rollers to be sufficient for reliable frictional engagement and driving by belts of the left and right branch. Having passed working position I, the fish advances to position II, in which the middle belt of the left branch is directed by roller 384 to be remote from the fish body, thus providing room for a left middle nozzle 261m. The height of this room defines left middle zone B, which is available between upper and lower belts, guided by upper and lower rollers 385,386. Nozzle 261m directs high-pressure water jet to the left middle zone B, which has not been treated yet. Three belts of the right branch touch the right side of the fish by virtue of common roller 387, situated proximate to the fish body. After completing the treatment of the left side, the fish proceeds to working position III, in which its right side is treated. Upper right zone C and lower right zone D are treated first by water jets, emerging respectively from nozzles 26ru, 26rb. The middle zone B is in contact with the belt of the right branch, directed by roller 388. The upper and lower belts of the right branch are directed by common roller 389 to be remote from the right side. The opposite side of the fish is in contact with the all three belts of the right branch, directed by common roller 390. After completing the treatment in position III the fish proceeds further to working position IV, where the right middle section B of the fish body is treated by water jet emerging from the right middle nozzle 26rm. The upper and lower zones C, D are in contact with the upper and lower belt of the right branch. Corresponding guiding rollers direct these belts. The middle belt of the right branch is kept remote from the right side of the fish by virtue of guiding roller 393. The left side of the fish is in contact with the all three belts of the left branch guided by a common roller 394. Thus the sequence of treatment of the right side is the same as of the left side due to similar design of the right branch and due to similar construction and location of rollers and nozzles. While the fish advances from position I to IV, water jets are also directed to the lower part of the fish body. The jets emerge from dedicated bottom nozzles 26b arranged along the treatment path under each working position. The fish is moving along the treatment path uninterruptedly, one after another, and since all the nozzles operate simultaneously several fish are cleaned at a time. In Fig.5 it is shown how fish is advanced along the treatment path being driven by three conveyor belts at the left side and by two conveyor belts at the right side. The treatment area is above level A of the treatment path and is separated therefrom by a distance H. This distance is selected to ensure, that irrespective of the fish size H2, shown in Fig.l the belly area would never be compressed laterally between opposite belts. The lower part of the fish body is exposed to water jets emerging from the bottom nozzles (not shown). By virtue of this provision the belly area is carefully washed around by water. Furthermore, by virtue of the above explained positioning it is ensured that the belts compress only hard tissues of the fish body. Spring means 36 is selected to provide for lateral compression force, which is required to ensure reliable frictional engagement and transporting the fish by belts, without however puncturing the tissues. In practice the spring means should be suitable to exert lateral compression force of 2 kg on either side. Now, referring to Fig.4d we are going to explain construction of nozzles employed in the present invention. Each nozzle is configured as cylindrical bushing, provided with an orifice 40 having diameter d. The rear end of the nozzle is provided with a screwed portion S and the forward end is formed with a diametrical groove 42, having V-shaped cross-sectional configuration. The groove angle φ and diameter d of the orifice are chosen in such a manner that water jet, emerging from the nozzle would provide a reliable scaling. In practice, for water jet supplied under 14-16 bar pressure diameter d is 3 mm and angle φ is 50+2 deg. By virtue of this provision it is possible to deliver a flat fan-shaped jet, which is very efficient for removing the scales. It is advantageous to dispose the nozzles in working positions in such a way, that adjacent nozzles deliver overlapping water jets and thus to ensure better scaling. The optimal distance between the nozzles and the fish surface is established empirically. This distance is kept constant irrespective of the fish thickness by proper positioning the guiding rollers. Having passed scaling, the fish by means of the same conveyer is transported along the treatment path to the position for the removal of internal organs. As seen in Figs.4e, 4f this position is provided with rotating cutting disc 32 for cutting the fish belly. Residing in the beginning of this position a lever mechanism 44 is provided. This mechanism aligns the fish with the cutting disc by virtue of dedicated rollers 46,48, mounted on respective levers and connected therebetween by a spring means 50. As seen in Fig.2b the lever mechanism keeps the distance B between rollers and the disc constant and thus ensures that the fish gripped between rollers is always cut along its middle plane, coinciding with the plane of the cutting disc. Referring to Fig.2a it is seen that cutting disc protrudes above level A of the treatment path by a distance h to ensure that the cut is sufficiently deep and provides for easy removal of viscera. Furthermore, the alignment ensures that the fish is cut through its anus and thus removal of viscera is even more facilitated, since the major part of the viscera is held up in the anus. Conveyor advances the cut fish further to cleaning position, which is located beyond the disc. In this position an expanding means 52 is provided, which has conical end 54 facing the fish and forcing the belly walls apart. Mounted beneath the cleaning position nozzles 60,62 are provided, which supply water for cleaning the belly and outwashing the entrails. It is advantageous if the nozzles are directed to the fish belly at a small inclination, facing one another. The entrails and dirty water are easily evacuated from the cut belly by gravitation. The clean fish is evacuated from the apparatus via discharge tray 64. By virtue of the above described method and apparatus a very high quality of fish scaling is ensured combined with complete cleaning of the fish from viscera. It should be understood that the present invention should not be limited to the above described example and embodiments. One ordinarily skilled in the art can make changes and modifications without deviation from the scope of the invention. The scope of the present invention is defined in the appended claims. However it should be understood that the features disclosed in the foregoing description, in the following claims and/or accompanying examples may separately and in any combination thereof, be material for realizing the present invention in diverse forms thereof.

Claims: What is claimed 1. A method for scaling fish and removing its internal organs, in which the fish is advanced in a longitudinal direction along a treatment path while the fish body is exposed to water jets, said method comprising a) positioning the fish on the treatment path with its belly being downwards and its head forward b) applying lateral forces substantially to the upper part of the fish body to enable holding the fish and its advancement along the treatment path. 2. The method as defined in claim 1 , comprising positioning the fish on a reference plane while the longitudinal middle plane of the fish body being perpendicular to the reference plane. 3. The method as defined in claim 2, in which the level of said reference plane is selected to prevent applying lateral forces to the belly area. 4. The method as defined in claim 1 , comprising successive advancing the fish from scaling position to position for removing internal organs. 5. The method as defined in claim 4, comprising cutting the belly area in the position for removing internal organs. 6. The method of claim 3, comprising exposing the opposite lateral sides of the fish body to high-pressure water jets. 7. The method of claim 6, in which said high-pressure water jets are delivered under pressure 14-16 bar. 8. The method of claim 7, in which opposite lateral sides of the fish body are exposed to said high-pressure water jets not simultaneously. 9. The method of claim 8, in which one lateral side of the fish body is exposed to high-pressure water jets only after completing treatment of the opposite lateral side. 10. The method of claim 9, comprising directing said high-pressure water jets to various zones of lateral side. 1 1. The method as defined in claim 6, comprising exposing the belly area to water jets. 12. The method of claim 5, comprising aligning the longitudinal middle plane of the fish body with the plane of the cutting disc. 13. The method of claim 5, comprising forcing the belly walls apart to facilitate evacuation of internal organs. 14. A device for fish scaling and cleaning its internal organs by means of high pressure water jets, said device comprising a) A supporting frame suitable for mounting various components of the device, said frame defines a treatment path, along which the fish proceeds from scaling position to position for removing internal organs b) a transporting means, suitable for advancing the fish along the treatment path, wherein the fish is positioned during transportation with its belly area downwards c) a water jet delivery means, suitable for producing high-pressure water jets and directing the jets to the fish body d) a cutting means suitable for cutting the belly area to enable evacuation internal organs therefrom. 15. The device as defined in claim 14, in which said transporting means comprises endless conveyor, consisting of two opposite branches, arranged at lateral sides of the treatment path to transport the fish along the treatment path. 16. The device as defined in claim 15, in which said water jet delivery means comprises pump and plurality of nozzles, directing the water jets to various zones of the fish body. 17. The device as defined in claim 16, in which each of the branches comprises three parallel belts, directed by corresponding guiding rollers, said rollers are located in such a manner that one lateral side of the fish body is always in frictional engagement either with one or with two belts of the one branch, while the opposite lateral side of the fish body is in frictional engagement with all three belts of the opposite branch and there is provided a room between the fish body and those belts, which are not in frictional engagement with the fish body, said room is sufficient for deployment therein of at least one nozzle for directing high- pressure water jet to the corresponding lateral side of the fish body. 18. The device as defined in claim 16, comprising a spring means for maintaining constant distance between the opposite belts, said spring means is sufficient to exert lateral force on each fish side, said force is sufficient for frictional engagement and reliable advancing the fish along the treatment path without however damaging the fish body tissues. 19. The device as defined in claim 18, in which said nozzles are configured to provide jet discharge in the form of flat fan-shaped flow. 20. The device as defined in claim 14, comprising alignment mechanism for alignment the middle longitudinal plane of the fish body with the plane of the cutting disc.

Inventors: PURETZ AVROHOM, PURETZ, AVROHOM
Applicants: JERSEY GLOBAL INTERNAT S A, PURETZ AVROHOM, JERSEY GLOBAL INTERNATIONAL S.A., PURETZ, AVROHOM
Application year: 2000
Main classification: A22C25
IPC codes: A22C25