Abstract
A method of treating a meat-substance containing a bone structure. The bone marrow is coagulated with microwaves generated by a solid-state RF energy source. The microwave heating may be carried out prior to a heat treatment of the meat-substance and/or may be carried out after slaughtering and before the fresh slaughtered meat-substance is frozen.
Claims
1. A method of treating a meat-substance containing a bone structure comprising bone marrow in an apparatus, the method comprising: coagulating the bone marrow with microwaves generated by a plurality of solid-state RF energy sources, wherein the apparatus comprises a housing, a conveyor for conveying the meat-substance through the housing, the meat-substance is configured to be arranged on the conveyor in rows, the plurality of solid-state RF energy sources are arranged in rows on the apparatus, the rows of the plurality of solid-state RF sources are configured to be aligned with the rows of the meat-substance on the conveyor such that one or more of the rows of the meat-substance arranged on the conveyor pass under a respective one of the rows of the plurality of solid-state RF sources, wherein the apparatus comprises a cooling chamber comprising a cooling agent, the cooling chamber is located in between the housing and the conveyor, the cooling chamber surrounds the conveyor, wherein the method comprises measuring a temperature of one of more of the plurality of solid-state RF energy sources, and then based on the measuring step, the method comprises controlling a fluid flow of the cooling agent and/or a temperature of the cooling agent to cool the plurality of solid-state RF energy sources.
2. The method according to claim 1, wherein the coagulating is carried out prior to a subsequent heat treatment of the meat-substance.
3. The method according to claim 2, wherein the coagulating is carried out after slaughtering and before a step of freezing the meat-substance.
4. The method according to claim 1, wherein the meat-substance is thawed and then subjected to a subsequent heat treatment.
5. The method according to claim 4, wherein the bone marrow is heated during a thawing step.
6. The method according to claim 4, wherein the subsequent heat treatment step is carried out in an oven or a fryer or prior to a step of freezing the meat-substance.
7. The method according to claim 1, wherein a power level, frequency, wavelength, phase versus time, amplitude, magnitude of radiated power and/or direction of the plurality of solid-state RF-energy sources is set such that radiation penetrates the meat-substance and the bone structure.
8. The method according to claim 1, wherein a temperature of the bone structure and/or the bone marrow is measured during the coagulating step.
9. The method according to claim 8, wherein a signal of a temperature measurement is utilized to control the plurality of solid-state RF-energy sources.
10. The method according to claim 1, wherein the meat of meat-substance is at least partially frozen without freezing the bone structure and simultaneously and/or afterwards the bone marrow is coagulated with the microwaves generated by the plurality of solid-state RF energy sources.
11. The method according to claim 10, wherein, the meat of the meat-substance is heated to 60? C.-100? C.
12. The method according to claim 10, wherein the meat-substance is frozen to ?10? C. or less.
13. The method according to claim 1, wherein the method comprises controlling the plurality of solid-state RF energy sources with a control system by comparing transmitted energy with reflected energy and then based on the comparing step, the method comprises a step of adjusting new energy transmitted by the plurality of solid-state RF energy sources.
14. The method according to claim 1, wherein the method comprises measuring a temperature of the bone marrow with a temperature sensor.
15. The method according to claim 1, wherein before the coagulating step, the method comprises freezing the meat-substance without freezing the bone structure and the bone marrow.
16. The method according to claim 15, wherein the method comprises a step of measuring a temperature of the bone marrow with a temperature sensor.
17. The method according to claim 16, wherein the meat of meat-substance is at least partially frozen without freezing the bone structure and simultaneously the bone marrow is coagulated with the microwaves generated by the plurality of solid-state RF energy sources.
18. The method according to claim 16, wherein the meat-substance is treated with the microwaves generated by the plurality of solid-state RF energy sources until the bone marrow is entirely coagulated and after the bone marrow is entirely coagulated, the method comprises freezing the meat-structure.
19. The method according to claim 1, wherein the cooling agent is water.
20. The method according to claim 1, wherein the cooling agent is gas or air.
Description
BRIEF DESCRIPTION OF THE FIGURES
(1) FIGS. 1a-1c, 2a-2c, 3a-3c, 4 and 5 each depict a heat treatment line 1 comprising conveyor means.
(2) FIGS. 6, 7, 8, 9, 10, 11, and 12 each depict an embodiment of the inventive method
DETAILED DESCRIPTION
(3) FIGS. 1a-1c depict a heat treatment apparatus 1 comprising conveyor means 10, here an endless belt, running through a housing 8, here a tunnel shaped housing, provided with an inlet 21 and an outlet 20, which are separated from each other. The substances 11 is transported past at least one, preferably a multiple, of solid-state RF energy sources 2. The housing 8 can extend in the transport direction around the substances 11 to be heat treated and/or around the conveyor means 10. The housing preferably comprises a slot at the inlet and at the outlet for the conveyor means 10. The housing 8 can be similar to a Faraday cage preventing electromagnetic waves coming out of the housing. At least the inner wall 9, but preferably the entire housing 8, can be made of metal, preferably steel, for instance stainless steel to shield the electromagnetic radiation. In a preferred embodiment, the housing 8 comprises reflection- and/or absorption means at its inner surface to at least partially eliminate radiation from external sources that enters the housing through the inlet and/or the outlet. The reflection- and/or absorption means avoids that this electromagnetic radiation reaches the antenna 17. The radiation from the multiple antennas preferably need not have to be shielded from each other.
(4) The number of solid-state elements 2/antennas 17 preferably depends on, for instance, the required heating power, the width of the belt, the length of the housing, the number and/or size and/or consistency of substances 11, the position of the substances on the belt, the speed of the belt and/or the desired accuracy and/or speed of the heat treatment process, particularly the uniformity of the heating process. FIGS. 1a-1c show an embodiment with multiple solid-state elements 2/antennas 17 positioned in each and every line of food substances. The substances 11, here provided in arrays, are transported continuously or intermittently from the inlet 21 to the outlet 20 and past the solid-state RF energy sources 2, which emit microwaves, which heat the substances 11. Preferably, a multitude of rows, here five, of elements 2/antennas 17 are provided along the path of the substances 11. The rows of solid-state elements 2/antennas 17 are provided preferably equidistantly and/or each line comprises a multitude of solid-state elements 2/antennas 17, which are preferably arranged perpendicular to line of transportation of the substances 11. In each row, the solid-state elements 2 are preferably arranged equidistantly. Each solid-state element 2 is preferably controlled individually and/or each solid-state element 2 or a group of solid-state elements 2/antennas 17 in one line are controlled individually.
(5) Regarding the embodiment of FIGS. 2a-2c, reference can be made to the disclosure regarding FIGS. 1a-1c. FIGS. 2a-2c show an embodiment wherein the heat treatment apparatus 1 is provided with multiple, here three solid-state elements 2/antennas 17, here above the substances and two in one of the two sidewalls of housing 8. In this example, the substances are arranged in an array and transported as an array past the solid-state elements 2/antennas 17.
(6) FIGS. 3a-3c depict an embodiment with randomly oriented meat substances on the conveyor means 10. Otherwise, reference is made to disclosure regarding FIGS. 1a-1c and FIGS. 2a-2c.
(7) Regarding the embodiment according to FIGS. 4a-4c reference is made to the disclosure according to the previous Figures. FIGS. 4a-4c depict a cross view and a detail of an embodiment of a solid-state RF energized microwave apparatus. The solid-state energy sources 2 comprise a waveguide 16 and/or an antenna 17. The energy sources are preferably in direct contact with chamber 14 wherein the substances can be (pre)heated and/or (pre)cooked. Preferably microwave transparent shielding means 23 are provided to prevent pollution of the waveguide and antenna for example with the food substance.
(8) Regarding the embodiment according to FIG. 5 reference is made to the disclosure according to the previous Figures. FIG. 5 depicts a cross view of an embodiment of a solid-state RF energized microwave apparatus wherein a cooling chamber 18 is provided which is connected to a cooling circuit for instance a water cooling- and/or a gas-, preferably air-, cooling circuit. Shielding means 23 as depicted in FIGS. 4a-4c are preferably provided to protect the solid-state element 2/antenna 17 against the cooling medium. Despite this efficient energy management additional cooling of the waveguides and connected antennas may be desirable in case of high energy output, for example during a long period of operation time. In another not depicted embodiment the solid-state RF energy source can be cooled and/or its power supply. This can be done per RF energy source 2 if needed. The cooling of the solid-state RF energy source(s) is preferably controlled by a temperature measurement, which measures the temperature of one or more of the RF energy source 2 and based on this reading controls a fluid flow of the cooling agent and/or its temperature.
(9) FIG. 6 depicts a first embodiment of the inventive method. The meat substance is provided through an inlet 21 into an apparatus 5 in which the marrow of the bone of the meat structure is at least partially, preferably entirely coagulated by microwaves generated by solid-state RF energy source. Due to this coagulation, the coloring of the meat due to marrow migration through the bone into the meat in the subsequent heat treatment step 7 is minimized. The heat treatment step can for example be frying, browning, smoking, cooking and/or heat treatment by subjecting the food substance to impingement with hot air and/or super-heated steam. Subsequently, the meat product exits the line, as symbolized by arrow 20 and is for example frozen and/or packaged. The skilled person understands that the heat treatment is optional.
(10) FIG. 7 depicts a second embodiment of the inventive method. In the present example, preferably freshly slaughtered meat substance, which was not yet been frozen is provided through an inlet 21 into an apparatus 5 in which the marrow of the bone of the meat structure is at least partially, preferably entirely coagulated by microwaves generated by solid-state RF energy source. Subsequently, the meat substance including bone marrow/bone structure will be frozen 3A in a freezer, before it is for example packaged.
(11) FIG. 8 depicts a third embodiment of the inventive method. The meat substance is provided through an inlet 21 into a thawer 4 in the meat substance is thawed. In the same apparatus before, during and/or after, but preferably during, the thawing, the marrow of the bone of the meat structure is at least partially, preferably entirely coagulated by microwaves generated by solid-state RF energy source. Due to this coagulation, the coloring of the meat due to marrow migration through the bone into the meat in the subsequent heat treatment step 7 is minimized. The heat treatment step can for example be frying, browning, smoking, cooking and/or heat treatment by subjecting the food substance to impingement with hot air and/or super-heated steam. Subsequently, the meat product exits the line, as symbolized by arrow 20 and is for example frozen and/or packaged. The skilled person understands that the heat treatment is optional.
(12) FIG. 9 depicts a fourth embodiment of the inventive method. The meat substance will first be frozen 3B preferably without freezing the bone structure and bone marrow. By freezing the meat substance, preferably in a range between 0 and ?20? C., it will be highly transparent to microwaves. In a next step 5 microwave energy generated with solid-state RF energy sources will be applied in order to coagulate the bone marrow. The temperature of the meat around the bone structure should be increased up to the desired temperature, preferably between 60? C. and 100? C. (reduction of bacteria to a safe level). Due to the frozen meat substance the meat will accumulate less microwave energy. In a next step the food product will be finally frozen 3A.
(13) This process is advantageous for further processing of the product, because the meat substance needs later only to be heated until a temperature of for instance 72? ? C. while the bone marrow/structure is already cooked until the desired temperature, i.e the bone does not need to be heated. This will reduce the residence time (shorter process time) within the oven resulting in less evaporation of food substance moisture and less energy consumption.
(14) FIG. 10 depicts a fifth embodiment of the inventive method similar to FIG. 9 except after coagulation 5 the substance will in this embodiment be subjected to heat treatment step 7.
(15) FIG. 11 depicts a sixth embodiment of the inventive method. The meat substance and preferably not the bone marrow/bone structure will simultaneously be frozen 3B and subjected to a heat treatment with solid-state RF energy sources in order to coagulate 5 the bone marrow. This method results in relatively small ice crystals preventing ice crystals from breaking down the bone structure. Freezing will take place from the outside to the inside and coagulation of the bone marrow will take place at the inside. After this combined step 3B/5 and/or after coagulation 5 of the bone marrow has finished freezing will be continued till the entire food substance including bone marrow is frozen 3A to the right temperature.
(16) FIG. 12 depicts a seventh embodiment of the inventive method similar to FIG. 11 except after freezing 3B/coagulation 5 the substance will in this embodiment be subjected to heat treatment step 7.
(17) All described embodiments are directed to microwaves generated by solid-state RF energy sources however the described embodiments can also be applied by microwaves generated by a magnetron.
LIST OF REFERENCE SIGNS
(18) 1 processing apparatus, microwave apparatus, heat treatment apparatus 2 solid-state RF energy source 3A freezing meat substance including bone marrow/bone structure 3B freezing meat substance and preferably not freezing bone marrow/bone structure 4 Thawing 5 solid-state RF energy source microwave marrow coagulation 7 further heat treatment 8 housing 9 inner wall housing 8 10 conveyor means 11 product, food product, substance 13 solid-state RF energy source microwave drying 14 product chamber, cooking chamber 16 waveguide 17 antenna 18 cooling chamber 20 outlet, exit 21 inlet 23 microwave transparent shielding means
