Method and apparatus for producing a foamed meat or fish product

Abstract

The invention relates to a method of producing a foamed meat product, comprising the steps of: feeding a pumpable raw material containing comminuted meat or fish and strand-like connective tissue components to a dispersing apparatus with a chamber with a cylindrical rotor arranged therein, which is provided, on its circumference, with a number of cavities to create cavitation, feeding a gas to the dispersing apparatus and operating the dispersing apparatus while creating cavitation and dispersing the gas supplied, in the process of which the sinews or ligaments are passed through the chamber, and creating a foamed meat or fish product containing strand-like connective tissue components, which can be sterilised.

Claims

1. A system for producing a foamed meat or fish product, said system comprising: a shock wave reactor that accepts a gas and meat mixture and produces the foamed meat or fish product; and a back pressure valve for providing an overpressure to components of the system upstream of the back pressure valve, further comprising at least a first comminution apparatus operably disposed upstream of the shock wave reactor that receives a source of meat and/or fish and provides a comminuted meat/fish preparation.

2. The system of claim 1, further comprising a gas supply unit operably disposed relative to the at least a first comminution apparatus to provide gas to the comminuted meat/fish preparation.

3. The system of claim 2, further comprising a second comminution apparatus, at least one mixer, a return line operably disposed relative to the shock wave reactor, at least one cooling apparatus, or a combination of these.

Description

(1) The invention will now be explained by describing worked embodiments, reference being made to a drawing, in which

(2) FIG. 1 shows a worked embodiment of an apparatus in accordance with the invention.

(3) FIG. 2 shows a section view of a first variant of a dispersing apparatus,

(4) FIG. 3a shows a section view of a second variant of a dispersing apparatus,

(5) FIG. 3b shows a schematic view of the second variant of the dispersing apparatus,

(6) FIG. 3c shows a view of the dispersing apparatus according to FIG. 3b in cross-section,

(7) FIG. 3d shows a perspective view of a rotor of the dispersing apparatus according to FIG. 3b,

(8) FIG. 4 shows details of the supply of gas to the dispersing apparatus,

(9) FIGS. 5 a-d show a static mixing element in a number of views,

(10) FIG. 6 shows a cumulative frequency distribution of the gas bubble sizes in the foamed, sterilised meat product, and

(11) FIG. 7 shows a detailed gas bubble size distribution.

(12) The method and apparatus of the invention will be explained below with reference to the exemplary illustration of an apparatus for producing a meat product in accordance with FIG. 1 which contains gas bubbles or is foamed.

(13) Meat (and/or fish) to be processed in accordance with the invention is fed in a cooled or frozen state to a comminution apparatus 2, in which it is chopped to a size that makes it possible to process the foamed product. Comminution to a size of less than 3 mm, preferably less than 1 mm, less than 0.5 mm or less than 0.1 mm is appropriate. In the process, meat fibres and any bones present can be comminuted to the dimensions stated. Since, however, sinews, ligaments, twisted connective tissue membranes and similar elements are very difficult to comminute, because of their structure and strength, they may remain with little comminution or uncomminuted in the otherwise comminuted meat.

(14) It may be provided in this context that, in addition to the amount of strand-like connective tissue components, such as sinews and/or ligaments, which is present in any case in the meat or fish to be processed, an additional amount may be added as well, which may come, for example, from the processing of meat into products in which a content of connective tissue components such as sinews or ligaments is undesirable and from which the latter are removed.

(15) A sample formulation for the production of a foamed meat product will now be explained. A portion of meat and animal by-products (especially poultry liver, poultry gizzards, poultry separator meat, pigs' stomachs, pigs' lungs) amounts to approx. 45 to 55% by weight, especially 52% by weight. Water is added in a proportion of approx. 30 to 40% by weight, especially 36% by weight. Emulsifiers and salts are also added.

(16) A first pump 4 conveys the comminuted meat to a mixer 6, in which additives are metered in as required and depending on the formulation and mixed with the meat. Examples of such additives are water, fat, oil, salt, ice, emulsifiers, spices, gels, vegetable components, leaves, fibres, vegetables, cereals, starch, hydrocolloids, proteins, minerals, colorants and preservatives in comminuted or uncomminuted form.

(17) A second pump 12 conveys the meat preparation further to a fine comminution apparatus 14, which forms an emulsifying station at the same time.

(18) After the mixture exits the emulsifier 14 and, where applicable, a further pump 12, a gas with which the meat preparation is to be foamed is supplied at a gas inlet 16. In principle, any gas suitable for use with foodstuffs may be used for this purpose, such as helium, hydrogen, nitrogen, oxygen, argon, NH.sub.3, N.sub.2O, CO.sub.2, air etc., though those gases are particularly suitable which are both inert, i.e. oxygen-free in particular, and which exhibit the lowest possible solubility in water, or in the meat preparation to be foamed. Nitrogen exhibits considerably lower solubility than CO.sub.2 and is therefore preferable as a matter of principle.

(19) A gas-supply unit, here for example a pressure-swing adsorption unit 18 (FIG. 4), supplies pressurised nitrogen via an air filter, a pressure reducing valve 20, a flow meter 22, a needle valve 24, a cut-off valve 26 and a check valve 28 to the gas inlet 16, where the gas enters the comminuted and emulsified meat preparation in metered form.

(20) The gas/meat mixture is delivered to a dispersing apparatus 30 in the form of a shock wave reactor, in which the gas is dispersed into small gas bubbles. The structure and action of the dispersing apparatus 30 are explained by FIGS. 2 and 3.

(21) FIG. 2 shows a first embodiment of the dispersing apparatus 30 (shock wave reactor) and FIG. 3 a second embodiment in various views, which consists substantially of a cylindrical chamber 32 closed on all sides, in which a rotor 34 is mounted such as to be rotatable about an axis of rotation 36. The rotor 34 is likewise cylindrical and is spaced apart on all sides from the peripheral and end walls of the chamber 32, so that the space formed in this way (free chamber volume) is filled with the gas/meat mixture to be processed.

(22) Arranged on the periphery of the rotor 34 are a number of radially aligned bore holes 40, which lead in a manner known per se to the formation of shock waves and cavitation bubbles, which collapse and lead in this way to a fine dispersion of the gas supplied. The dispersion process is indicated in FIG. 2 in that the gas supplied is present in relatively large bubbles 42, whereas the product exiting contains finely dispersed gas bubbles, which are merely hinted at in FIG. 2.

(23) The cavitation bubbles formed collapse principally in the interior of the bore holes 40 and lead to extremely great shear forces and pressure waves, which result not only in a particularly fine dispersion of the gas supplied, but also in a relatively uniform size distribution, or in a limited scatter in the size distribution of the gas bubbles formed.

(24) When the dispersing apparatus 30 is started or restarted, the desired product quality is not obtained immediately, but experience has rather shown that about 1 to 2 times, preferably 1.5 times the free chamber volume must be passed through the dispersing apparatus before a steady operating state is reached. In order to avoid having to reject as waste the material produced during such a starting-up period which does not meet the requirements, a return line 44 and optionally a further pump 12 is provided, with which the material can be circulated via the dispersing apparatus 30. A cooling apparatus 46 ensures that the heat introduced into the product by the dispersing apparatus 30 is dissipated, because the gas bubble content means that heating of the product is undesirable, and also that emulsified fats remain largely solid. A temperature of less than 30 C., preferably less than 25 C., 20 C., 17 C., 15 C., 12 C. or between 2 C. and 8 C., and especially 5 C. is appropriate. During the recirculation of the product, neither gas nor meat preparation is supplied.

(25) Material exiting the dispersing apparatus 30 can be recirculated not only in the course of a startup process, but also, if the need arises, in the event of a delay in the filling area, so that the dispersing apparatus does not need to be switched off in such cases. In particular, it is appropriate to cool the recirculated material with the cooling apparatus 46 in such a case.

(26) In addition, it is possible to arrange a buffer container in any convenient location downstream of the dispersing apparatus 30, such as after the mixing head 82 or immediately before the filler head 94, which makes it possible to receive a certain amount of the foamed meat or fish product, such as 10, 20, 50 or 100 times a amount envisaged for filling a container, so that a corresponding number of containers can be filled from the buffer container. Since the throughput of the dispersing apparatus cannot as a rule be adjusted exactly to the flow of material which is filled through the filler head 94 averaged out over time, it is possible to have the dispersing apparatus 30 running in cycles until the buffer container is filled, then to switch it off and only to switch it back on when the buffer container has been emptied to a set residual level, such as 5% or 10% of its capacity.

(27) Two branches 52, 53 are arranged downstream of an outlet 50 from the dispersing apparatus 30, the first branch 52 leading to the cooling apparatus 46, and a first partial flow path 54 and a second partial flow path 56 following on from the second branch 53. The first partial flow path 54 can be closed with a cut-off valve.

(28) First of all, an inlet 60 for additives is provided in the second partial flow path 56, to which a colorant metering pump 62 is connected in the example illustrated. Alternatively, any other additive could be introduced at this point, e.g. vegetables or cereal paste, gels, aspic, gravy, dairy products, hydrocolloids, starch, proteins, minerals, colorants and preservatives, and/or a meat or fish emulsion or a suspension containing pieces of meat or fish can be dispersed in.

(29) After the inlet 60 comes a static mixing unit 64, in which a series of static mixing members 66 are arranged. FIG. 5 shows a static mixing member 66 in different views, the mixing member consisting substantially of a length of cylindrical pipe with mixing surfaces 68 arranged radially and axially and pointing inwards, and with a mixing finger 70 arranged between them.

(30) When the throughput is sufficient, a good mixing effect results, so that the additive previously introduced is mixed with the foamed meat product. When the throughput is low, a dispersing effect is caused. Because of the arrangement of the inclined mixing surfaces pointing down-stream and the mixing fingers, fibre-like components of the foamed meat product and especially the sinews, ligaments etc. contained in it, can move through the mixing members with no difficulty and do not become trapped. Preferably, a number of mixing members 66 are arranged in series, especially aligned at 90 to one another, as is made clear by positioning projections 72 and corresponding positioning recesses 74 arranged at 90 thereto, which are disposed on the respective axial ends of a mixing member and with which two adjacent mixing members can be coupled in a positive fit.

(31) The first partial flow path 54 is connected to a first inlet 80 of a mixing head 82, while the second partial flow path 56 is connected to a second inlet 84 of the mixing head 82.

(32) In operation, it can be provided that that 50% to 95%, such as 85%, of the material exiting the dispersing apparatus 30 flows through the first partial flow path 54, while the remaining amount flows through the second partial flow path 56 and the static mixing unit 64.

(33) A filler head 94 serving as a metering apparatus follows the mixing head 82. In this context, it is proposed that the material exiting the dispersing apparatus 30 is introduced into the filler head 94 via a back-pressure valve 95 and a static mixing unit 64. The arrangement of a back-pressure valve has the advantage that upstream, i.e. in the dispersing apparatus 30, a particular minimum pressure can be maintained, e.g. at least 1.5 bar or a pressure between 2 and 2.5 bar. At least one pressure sensor 98 and a density measuring device 97 are provided in order to ensure that as far as the filler head 94 an overpressure of approx. 0.5 to 6 bar, preferably 1 to 4 bar and more preferably 1.5 to 3 bar prevails within the material conveyed. The reason why this is important is that, because of the gas content, the foamed material must as far as possible not be exposed to a partial vacuum in certain cases, in order not to impair the gas bubble structure.

(34) Alternatively, a conventional filling apparatus can be installed downstream of the mixing head, with an intake and dispensing station, at which material coming from the mixing head is optionally drawn in metered amounts and dispensed in metered amounts.

(35) Beneath the filler head there are scales, with which the filling of a particular container 102 is monitored and the filling procedure is terminated. Downstream of the filler head, there is a metering apparatus 106 for lumpy additives. After that, closing, sealing 108 and sterilization 110 devices are positioned.

(36) After part of the available filling volume of the container 102, e.g. 70% to 90% of it, has been filled with the foamed meat product, the rest of the available filling volume, or part of it, can be filled with lumpy additives such as vegetables, fruit, cereals, pieces of meat, slaughterhouse by-products, meat analogues, pieces of fish, fish analogues, surimi, pieces of egg, pieces of fruit, nuts or pieces of nut.

(37) The invention is suitable for implementing various product concepts, such as a) meat or fish foam with nothing added, b) meat foam with vegetables and/or cereals added, c) meat foam with vegetable or cereal pastes introduced in a marbled pattern, the density of which is approx. 1 g/ml, d) meat foam with pieces of meat mixed in, slaughterhouse by-products and/or meat analogues (chunks), e) meat foam with pieces of meat and/or meat analogues in layers at the top or bottom, f) meat foam with a layer of gel/aspic at the top or bottom, which may also contain pieces of meat, meat analogues, pieces of vegetable or cereals, g) meat foam with pieces of meat, pieces of vegetable or meat analogues in layers at the top or bottom, which are present in a gravy, h) meat foam containing pieces of egg mixed in or in layers at the top or bottom, possibly in gravy or in gel/aspic, i) meat foam containing individual foods mixed in or in layers at the top or bottom, possibly in gravy or in gel/aspic (individual foods: meat or animal by-products, milk and dairy products, eggs and egg products, oils and fats, yeasts, fish and fish by-products, cereals, vegetables, vegetable by-products, vegetable protein extracts, minerals, sugar, fruits, nuts, seeds, algae, molluscs and crustaceans, insects, bakery products).

(38) One method of detecting connective tissue in fresh meat has been further developed on the basis of Strange and Whiting (Strange E. D., Whiting, R. C., Effects of added connective tissues on the sensory and mechanical properties of restructured beef steaks, Meat Science 27, (1990) pp. 61-74) for detecting connective tissue even in heat-treated, foamed fish/meat products:

(39) Materials:

(40) 1. Stainless-steel analytical sieve (0.300 mm), Retsch 2. 2,000 g 15% H.sub.3PO.sub.4 solution (20 C., pH 1; 1.5 M H.sub.3PO.sub.4) 3. 1,000 g 5% NaOH solution (20 C., pH 12.2; 1.25 M NaOH) 4. Aqua dest. (20 C.) for rinsing solid samples on the analytical sieve 5. Mixer 3MIX 7,000, Krups, mixing member: egg-beater 6. Colloid mill MK/MKO, IKA magic LAB, IKA GmbH & Co. KG, speed=12,000 r.p.m., 450 setting angle (1 turns on the setting ring: radial gap=0.398 mm 7. Laboratory analytical balance, Sartorius 8. Drying cabinet T 6030, Heraeus Thermo Scientific 9. Desiccator
Method: 1. Determine the dry mass (DM in %) of the sample (at 104 C. until constant weight is reached) 2. Comminute/stir approx. 50-55 g sample (weigh in precisely P) with 100 ml water for 30 s with a hand mixer on level 1 with egg-beaters. 3. Comminute the suspension through the IKA colloid mill: IKA MK/MKO (radial gap 0.398 mm=>1 turns); rinse the colloid mill with water. 4. Separate solids via a stainless-steel sieve with a mesh width of 0.30 mm. 5. Leave solids/residue for 5 hours in 500 ml NaOH solution (stir occasionally) 6. Separate solids again with a stainless-steel sieve with a mesh width of 0.30 mm. Rinse off caustic soda remaining on the sieve with water 7. Steep the sieve with the residue in the phosphoric acid for 60 seconds 8. Rinse the sieve with water 9. Dry the sieve at 104 C. until constant weight is reached 10. Weigh the dry mass retained (R) on the 0.30 mm sieve 11. Express the results: proportion of fibrous connective tissue [>0.30 mm; %]=((R)100)/((DM in %)(P))

(41) Amounts of connective tissue found in this way in foamed products before and after sterilisation:

(42) TABLE-US-00001 TABLE 1 Dried fibrous and solid connective tissue determined by washing out over 0.3 mm sieve (shown in % by Recovery rate of weight of the dry mass of the foamed fibrous and solid meat/fish product investigated) connective tissue, before sterilisation after sterilisation after 95% 95% sterilisation [%] Foamed confidence Aver- confidence after sterilisation meat/fish Average interval age interval Average product [%] +/ [%] [%] +/ [%] [%] with trout 10.56 2.65 1.13 0.29 10.71 with salmon 6.75 0.42 0.89 0.36 13.20 with beef 6.70 0.83 1.18 0.27 17.67 with chicken 7.19 1.15 0.73 0.14 10.13

(43) After sterilisation, lower figures are regularly found for the remaining strand-like connective tissue components, because the majority of the collagen from the membranes etc. is degraded to water-soluble gelatine during the sterilisation process. Sinews are detected very well with the method.

(44) TABLE-US-00002 TABLE 2 Dried fibrous and solid connective tissue determined by washing out over 0.3 mm sieve Recovery rate (shown in % by weight of the dry of fibrous and mass of the raw material used) solid connective before sterilisation after sterilisation tissue, after 95% 95% sterilisation [%] confidence confidence after sterilisation Average interval Average interval Average [%] +/ [%] [%] +/ [%] [%] Chicken liver 0.137 0.054 0.017 0.012 12.42 Pig's lung 8.504 0.604 1.177 0.651 13.84 Deboned turkey meat 2.516 0.247 0.100 0.025 3.96 Pig's stomachs 7.081 2.822 0.678 0.349 9.57 Cattle lung 12.075 1.918 2.492 1.148 20.64 Chicken gizzards 7.321 1.761 0.913 0.341 12.47 Trout cut-offs 3.626 0.328 0.381 0.136 10.51 Salmon cut-offs 4.740 0.344 0.388 0.117 8.19 Duck meat 0.953 0.160 0.090 0.013 9.42

(45) Table 2 shows the amounts and recovery rates of strand-like connective tissue components for different types of meat.

(46) The high proportion of larger connective tissue (larger than 0.30 mm) before foaming makes it clear how necessary it is to use a method that can process high viscosities irrespective of the fibres or pieces and which ensures a fine gas distribution.

(47) FIGS. 6 and 7 show a cumulative frequency distribution and a detailed gas bubble size distribution.

(48) The diameters of the gas bubbles of equal volume d.sub.3.2 in the sterilised foam range from approx. 20-2,000 m diameter. The mean was approx. 0.73 mm diameter.

(49) The Reynolds numbers when mixing or dispersing other pumpable components into the foam were found to lie in the range 0.0010<Re<0.0150.

(50) Pumpable component (vegetable paste): 0.0023<Re<0.0051.

(51) Average Re number at the mixing point: 0.0140<Re<0.3,000.

(52) The fluctuations are due to the formation of the average speeds: In one case, the average was formed over the mass, and in the second calculation it was formed over the flow surfaces.

(53) Formulation Information:

Example 1: Foamed Meat/Fish Product (Batch Size 80 kg)

(54) TABLE-US-00003 Vitamin/mineral/nutrition mix: 1.80% Emulsifiers (individually or a 1.00% combination of substances in accordance with the list of emulsifiers for animal feed from Community Register of Feed Additives pursuant to Regulation (EC) No 1831/ 2003, Appendices 3 & 4, Annex: List of additives (status: Released 21 May 2010.) Vegetable fibre powder 3.00% (SBP, cellulose) Hydrocolloid 0.20% (e.g. CMC carboxy-methyl- cellulose or individual or a combination of substances from the list of additives for animal feed from Community Register of Feed Additives pursuant to Regulation (EC) No 1831/2003, Appendices 3 & 4, Annex: List of additives (status: Released 21 May 2010.) Pigs' blood plasma powder 2.00% Turkey separator meat 5.00% Chicken gizzards 6.00% Pig's stomachs 12.00% Chicken liver 14.00% Pigs' lungs 15.00% Water 40.00%
Process Information:

(55) All the meat is frozen (18 C.) and comminuted to approx. 2020 mm.

(56) In a Paddle Mixer:

(57) 1st step: mix meat with minerals for 3 minutes.

(58) 2nd step: add half the water (30 C.) and mix for a further 2 minutes.

(59) 3rd step: add remaining dry ingredients, rotate for 1 minute in each direction.

(60) 4th step: add emulsifier and remaining water.

(61) Before emptying, mix for approx. one minute to drain. Total mixing time approx. 10 min.

(62) The meat mixture is now at a temperature of approx. +2 C. and is emulsified in an emulsifying apparatus through a combination of blades and 1.5 mm perforated disks. The mixture is now at a temperature of approx. 5 C.

(63) The mixture is then conveyed at a mass flow of 2.2 kg/min, with the addition of 2.2 l nitrogen or comressed air through a shock wave reactor (ex HydroDynamics, Rome, Ga., US). The speed of the rotor is 1,800 r.p.m. The rotor has a diameter of 304.8 mm and a width of 50.75 mm. 2 parallel rows of holes, each with 30 holes, are arranged on the circumference. The individual holes have a diameter of 18.8 mm and a depth of 50 mm. The volume of a hole is 13.5 ml. The distance between the circumference of the rotor and the fixed housing is =6.4 mm.

(64) The temperature of the foam obtained in this way is: 32.0 C. At this temperature, the foam can be filled directly, controlled by gravimetry, volumetry or pressure.

(65) After the foam has been filled in a suitable container (tin, bowl, pouch), and the latter has been sealed and sterilised thermally (T>110 C.), a stable product is obtained (fully preserved), which can be stored at room temperature for at least 2 years. The stable foam product is characterised by a homogeneous distribution of the gas bubbles, a moist, shiny, solid foam texture and a high level of acceptance by pets.

Example 2: Foamed Meat Product With Fish (Batch Size 80 kg)

(66) TABLE-US-00004 Vitamin/mineral/nutrition mix: 2.00% Emulsifiers (individually or a combination of 1.00% substances in accordance with the list of emulsifiers for animal feed from Community Register of Feed Additives pursuant to Regulation (EC) No 1831/2003, Appendices 3 & 4, Annex: List of additives (status: Released 21 May 2010.) Vegetable fibre powder (SBP, cellulose) 1.30% Hydrocolloid 0.20% (as in Example 1) Pigs' blood plasma powder 1.50% Turkey separator meat 5.00% Chicken gizzards 6.00% Pig's stomachs 12.00% Chicken liver 13.00% Pigs' lungs 13.00% Salmon by-products 7.00% Water 38.00%
Process Information:

(67) All the meat and fish materials are frozen (18 C.) and comminuted to approx. 2020 mm.

(68) In a Paddle Mixer:

(69) 1st step: mix meat with minerals for 3 minutes.

(70) 2nd step: add half the water (30 C.) and mix for a further 2 minutes.

(71) 3rd step: add remaining dry ingredients, rotate for 1 minute in each direction.

(72) 4th step: add emulsifier and remaining water.

(73) Before emptying, mix for approx. one minute to drain. Total mixing time approx. 10 min.

(74) The mixture of meat and fish is now at a temperature of approx. +2 C. and is emulsified in an emulsifying apparatus through a combination of blades and 1.5 mm perforated disks. The mixture is now at a temperature of approx. 5 C.

(75) The mixture is then conveyed at a mass flow of 2.0 kg/min, with the addition of 2.0 l nitrogen or comressed air through a shock wave reactor (ex HydroDynamics, Rome, Ga., US). The speed of the rotor is 2,200 r.p.m. The rotor has a diameter of 266 mm and a width of 50.75 mm. 2 parallel rows of holes, each with 24 holes, are arranged on the circumference. The individual holes have a diameter of 18.8 mm and a depth of 50 mm. The volume of a hole is 13.5 ml. The distance between the circumference of the rotor and the fixed housing is =6.4 mm.

(76) The temperature of the foam obtained in this way is 31.0 C. At this temperature, the foam can be filled directly, controlled by gravimetry, volumetry or pressure.

(77) After the foam has been filled in a suitable container (tin, bowl, pouch), and the latter has been sealed and sterilised thermally (T>110 C.), a stable product is obtained (fully preserved), which can be stored at room temperature for at least 2 years. The stable foam product is characterised by a homogeneous distribution of the gas bubbles, a moist, shiny, stable foam texture and a high level of acceptance by pets.

Example 3: Foamed Meat Product With Fish (Batch Size 80 kg)

(78) TABLE-US-00005 Vitamin/mineral/nutrition mix: 2.70% Emulsifiers (individually or a 1.00% combination of substances in accordance with the list of emulsifiers for animal feed from Community Register of Feed Additives pursuant to Regulation (EC) No 1831/2003, Appendices 3 & 4, Annex: List of additives (status: Released 21 May 2010.) Vegetable fibre powder (SBP, cellulose) 3.00% Hydrocolloid 0.30% (as in Example 1) Pigs' blood plasma powder 2.00% Turkey separator meat 4.00% Chicken gizzards 6.00% Pig's stomachs 11.00% Chicken liver 13.00% Pigs' lungs 12.00% Trout by-products 6.00% Water 39.00%
Process Information:

(79) All the meat and fish materials are frozen (18 C.) and comminuted to approx. 2020 mm.

(80) In a Paddle Mixer:

(81) 1st step: mix meat with minerals for 3 minutes.

(82) 2nd step: add half the water (30 C.) and mix for a further 2 minutes.

(83) 3rd step: add remaining dry ingredients, rotate for 1 minute in each direction.

(84) 4th step: add emulsifier and remaining water.

(85) Before emptying, mix for approx. one minute to drain. Total mixing time approx. 10 min.

(86) The mixture of meat and fish is now at a temperature of approx. +2 C. and is emulsified in an emulsifying apparatus through a combination of blades and 1.5 mm perforated disks. The mixture is now at a temperature of approx. 5 C.

(87) The mixture is then conveyed at a mass flow of 2.0 kg/min, with the addition of 2.0 l nitrogen or comressed air through a shock wave reactor (ex HydroDynamics, Rome, Ga., US). The speed of the rotor is 1,500 r.p.m. The rotor has a diameter of 203 mm and a width of 50.75 mm. 2 parallel rows of holes, each with 18 holes, are arranged on the circumference. The individual holes have a diameter of 18.8 mm and a depth of 50 mm. The volume of a hole is 13.5 ml. The distance between the circumference of the rotor and the fixed housing is 1=25.4 mm.

(88) The temperature of the foam obtained in this way is 21.0 C. At this temperature, the foam can be filled directly, controlled by gravimetry, volumetry or pressure.

(89) After the foam has been filled in a suitable container (tin, bowl, pouch), and the latter has been sealed and sterilised thermally (T>110 C.), a stable product is obtained (fully preserved), which can be stored at room temperature for at least 2 years. The stable foam product is characterised by a homogeneous distribution of the gas bubbles, a moist, shiny, stable foam texture and a high level of acceptance by pets.

(90) It is possible to use the following permitted additives:

(91) Emulsifiers for Animal Feed from: Community Register of Feed Additives Pursuant to Regulation (EC) No 1831/2003, Appendices 3 & 4, Annex: List of Additives (Status: Released 21 May 2010.)

(92) TABLE-US-00006 EC No. Additives: Emulsifiers E 322 Lecithins E 432 Polyoxyethylene(20) sorbitan monolaurate E 433 Polyoxyethylene(20) sorbitan mono-oleate E 434 Polyoxyethylene(20) sorbitan monopalmitate E 435 Polyoxyethylene(20) sorbitan monostearate E 436 Polyoxyethylene(20) sorbitan tristearate E 471 Mono and diglycerides of edible fatty acids E 472 Mono and diglycerides of edible fatty acids esterified with: a) acetic acid b) lactic acid c) citric acid d) tartaric acid e) monoacetyl and diacetyl tartaric acid E 473 Sugar esters (esters of saccharose and edible fatty acids) E 474 Sugar glycerides (mixture of saccharose esters and mono and diglycerides of edible fatty acids) E 475 Polyglycerine esters of edible fatty acids E 477 Monoesters of proylene glycol (1.2-propane diol) and of edible fatty acids, alone or mixed with diesters E 480 Stearyl-2-lactylic acid E 481 Sodium stearyl lactyl-2-lactate E 482 Calcium stearyl lactyl-2-lactate E 483 Stearyl tartrate E 484 Polyethylene glycol glyceryl ricinoleate E 487 Polyethylene glycol soybean oil fatty acid ester E 488 Polyethylene glycol glyceryl tallow fatty acid ester E 489 Polyglycerine ether with the alcohols obtained by reduction of oleic acid and palmitic acid E 491 Sorbitan monostearate E 492 Sorbitan tristearate E 493 Sorbitan monolaurate E 494 Sorbitan mono-oleate E 495 Sorbitan monopalmitate E 496 Polyethylene glycol 6,000 E 497 Polymers of polyoxypropylene-polyoxyethylene (M.G. 6,800-9,000) E 498 Partial polyglycerine esters of polycondensed ricinoleic fatty acids
Thickening and Gelling Agents for Animal Feed from: Community Register of Feed Additives Pursuant to Regulation (EC) No 1831/2003, Appendices 3 & 4, Annex: List of Additives (Status: Released 21 May 2010.)

(93) TABLE-US-00007 EC No. Additives: E 400 Alginic acid E 401 Sodium alginate E 402 Potassium alginate E 403 Ammonium alginate E 404 Calcium alginate E 405 Propylene glycol alginate (1.2-propane diol alginate) E 406 Agar-agar E 407 Carrageenan E 410 Carob seed flour E 411 Tamarind seed flour E 412 Guar seed flour, guar gum E 413 Gum tragacanth E 414 Gum arabic E 415 Xanthan gum E 418 Gellan gum E 440 Pectins E 460 Microcrystalline cellulose E 460(ii) Cellulose powder E 461 Methyl cellulose E 462 Ethyl cellulose E 463 Hydroxypropyl cellulose E 464 Hydroxypropyl methyl cellulose E 465 Methyl ethyl cellulose E 466 Carboxymethyl cellulose (sodium salt of the cellulose carboxymethyl ether) E 470 Sodium, potassium or calcium salts of the edible fatty acids, alone or mixed, obtained either from edible fats or from distilled edible fatty acids E 486 Dextrans E 498 Partial polyglycerine esters of polycondensed ricinoleic fatty acids E 499 Cassia gum

LIST OF REFERENCE NUMERALS

(94) 2 Comminution apparatus 4 First pump 6 Mixer 8 Second pump 12 Third pump 16 Gas inlet 18 Pressure-swing adsorption unit 20 Pressure controller 22 Flow meter 24 Needle valve 26 Cut-off valve 28 Check valve 30 Dispersing apparatus 31 Inlet for Dispersing apparatus 32 Chamber 34 Rotor 36 Axis of rotation 40 Bore hole 42 Gas bubble 44 Return line 46 Cooling apparatus 50 Outlet 52 Branch 54 First partial flow path 56 Second partial flow path 60 Inlet 62 Colorant metering pump 64 Static mixing unit 66 Static mixing member 68 Mixing surface 70 Mixing fingers 72 Positioning projection 74 Positioning recess 80 First inlet 82 Mixing head 84 Second inlet 94 Filler head 95 Back-pressure valve 97 Density measuring device 98 Pressure sensor 102 Container 106 Metering apparatus 108 Closing/sealing device 110 Sterilizing device