GB2225208A

GB2225208A - Cooling device for smoking oven

Info

Publication number: GB2225208A
Application number: GB8923554A
Authority: GB
Inventors: Alan Jackson
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-10-21
Filing date: 1989-10-19
Publication date: 1990-05-30
Also published as: GB8824703D0; GB8923554D0

Abstract

Coolers, comprising heat sinks such as water filled radiators, for use in smoking ovens to control the temperature of the smoke being used to smoke food are designed to remove both heat from the smoke and also radiant heat from the smoke generator. Figure 3 shows a cooler 31 in a smoke oven 20. <IMAGE>

Description

COOLERS FOR SMOKING OVENS This invention relates to coolers for ovens for smoking foods and relates in particular to coolers for use in ovens used for the cold smoking of foods.

Conventionally foods such as meats and fish are smoked in ovens or containers by burning for example wood chips in the bottom of the smoker or an adjacent smoke box and letting the smoke rise or pass to the smoker and smoke the food which is typically laid on racks. It has been found that the burning wood chips create a lot of heat which heats the food being smoked. This heating of the food whilst desirable in some forms of food smoking processes is undesirable in the cold smoking of foods such as fish because the heat effectively cooks the surface of the food forming a barrier preventing the smoke from penetrating and thus flavouring and preserving the food properly. Elevated temperatures can also encourage the growth of harmful bacteria.

A number of solutions, none of which are particularly satisfactory, have been tried to reduce the temperature of the oven and the smoke to prevent this unwanted overheating of the food. These solutions include, for example increasing the air flow in the smoking oven to try to reduce the temperature of the smoke, this tends to air dry the food, or by generating the smoke at a location remote from the oven and passing the smoke through long tubes, often refrigerated, before it is passed into the smoking oven where the food is located.

Another known solution is to have a smoking oven with hollow walls through which air is drawn to try and reduce the temperature of the smoke by taking heat from the oven. These prior art solutions are both expensive and not very effective in producing cool smoke. Furthermore they act by cooling or trying to cool the hot smoke and do not operate by reducing the heat output from the smoke source.

It is an object of the present invention to mitigate and obviate these problems and provide a device, for use in a smoking oven, which reduces the temperature of the smoke efficiently whilst being simple and easy to operate. It is a further object of the present invention to provide a process for smoking foods which process uses the aforesaid device to produce smoked food having a superior flavour to foods smoked in conventional smoking apparatus.

According to the present invention there is provided a cooling device for use in a smoking oven wherein said device comprises or includes a heat sink, whereby in use smoke from a smoke generator, for the smoking oven passes around the said heat sink before reaching the food to be smoked.

According to a further aspect of the present invention there is provided a process for smoking foods wherein said process comprises smoking foods in a smoking oven having a cooling device comprising or including a heat sink around which smoke is passed before the smoke reaches the food to be smoked.

By smoking oven is meant any container or apparatus which is adapted for smoking food. Typical smoking ovens are stainless steel boxes having sawdust smoking boxes in the base and racks above the tray for storing the food to be smoked.

By heat sink is meant any device which can be used to extract heat from the smoke oven, and in particular radiant heat from the heat source, e.g. burning wood chips, and transfer that heat away from the food to be smoked. Preferably the heat sink of the present invention will comprise or include water cooled radiators. These radiators will preferably be made from a material, such as metal, which transfers heat readily. Suitable metals include for example brass, copper and stainless steel. Preferably the heat sink will be in a form, including for example tubes and apertured radiators, which readily allows the smoke to be passed through it The heat sink is preferably placed above or close to the burning material that produces the smoke so as to absorb as much of the radiant heat from the burning material as possible as well as the heat associated with the smoke.However it will be appreciated that the heat sink may be placed anywhere where it can absorb radiant heat from the smoke source and where the smoke for the smoke oven can pass around it.

The heat sink is preferably water cooled with water from any suitable supply being fed into one end of the heat sink and allowed to flow from the other end of the heat sink thus taking heat away. It will be appreciated that other known heat sinks, including for example refrigerant tubes may also be employed in the present invention. It will also be appreciated that other heat transfer fluids, apart from water, may also be used to cool the heat sink.

In a preferred embodiment the temperature of the smoking oven can be monitored by a known temperature sensor and that information about the oven temperature used to control the rate of e.g. the water flow through the heat sink and thus control the rate of heat taken up by the heat sink thus controlling the temperature of the smoke. Equally it will be appreciated that when other heat sinks are used similar control mechanisms may be employed.

Food smoked by a process using the novel cooling device of the present invention has a superior taste to food smoked conventionally. In addition because the heat of the oven can be controlled readily it means that denser smoke can be used, because it does not increase the temperature as it would do in a conventional oven, thus the smoking times can be reduced with consequent cost savings. Additionally because the oven temperature is kept low and the air flow is reduced the degree to which the outside of the food is cooked or air dried is reduced. Furthermore it is possible, using the novel cooling devices of the present invention to prolong the smoking time without cooking or air drying the food thus increasing the flavour of the food.As an additional benefit this prolonged smoking with possible novel cooling devices of the present invention increases the antiseptic and natural preserving qualities of the smoking process.

An embodiment of the present invention will now be described by way of example only with reference to the following drawings in which Figure 1 is a schematic representation of a known smoking oven, Figure 2 is a schematic representation of another known smoking oven, Figure 3 is a representation of the oven shown in Figure 2 but incorporating a novel cooling device of the present invention and Figure 4 is a schematic representation of a cooling device of the present invention.

Referring now to Figure 1 this shows a smoke generator 1 remote from the smoking oven 2. The smoke is pushed from the smoke generator 1 by a fan 3 and then passed through a cooler 4 before it passes through a valve 5 into the smoke oven 2.

The smoke is then extracted by a fan 6 and exhausted to the air. It is clear from this example that a lot of expensive machinery is involved in trying to cool the smoke and that the cooler 4 cannot absorb any radiant heat from the smoke generator.

Referring now to Figure 2 this shows a smoke oven 20 having a smoke generator 21 comprising three boxes 22, which contain the material which creates the smoke, typically wood chips. The smoke created rises in the direction of arrows A smoking the food in the oven. Air is drawn through the smoke oven 20 by a fan 25 the air entering the oven by vents 26,27.

Air can also be drawn through the walls 28,29 of the smoke oven 20. This air flow in the walls is designed to cool the smoke oven and reduce the temperature inside the smoke oven.

The smoke and heated air are expelled at the top of the oven 30. Again the cooling air in walls 28 and 29 cannot absorb much of the radiant heat from the smoke generator 21.

Referring now to Figure 3 this shows a smoke oven 20 as shown in Figure 2 with the addition of a cooling device 31 of the present invention which is placed above the smoke generator 21. The cooling device 31 has an inlet pipe 32 and an outlet pipe 33 . The inlet pipe is connected to a suitable water supply, not shown, and the flow of water can be regulated by, for example a valve, not shown, so as to control the smoke oven temperature. The smoke A passes around the cooling device 31 and in addition the cooling device 31 is so placed as to absorb a lot of radiant heat from the smoke generator as well as absorbing heat from the smoke.

Referring now to Figure 4 this shows a plan view of a cooling device 31 of the present invention. The cooling device 31, which is made from copper, has an inlet pipe 32 and an outlet pipe 33 and a series of holes 34 through which the smoke can pass. The smoke passing over the cooling device 31 transfers heat to it thus cooling the smoke. It will be appreciated that cooling devices in other shapes including coils and additional devices for the collection of condensation may be employed. Equally it will be apprecaited that it is not necessary for all the smoke to pass over a cooling device of the present invention nor that the cooling device of the present invention covers all the area of the smoke generator.

Example 1 Salmon to be smoked according to an embodiment of the process of the present invention are prepared in a conventional manner and placed in a smoke oven fitted with a cooling device of the present invention. The cooling device is made operational and smoke is generated conventionally and passes through and around the salmon. The temperature inside the oven is maintained at or about 800F by controlling the cooling device and the salmon is left in the smoke for the required time. The smoked salmon can then be removed. It will be appreciated that any food may be smoked using this process.

It will also be appreciated that other time intervals and temperatures may also be employed.

Claims

1. A cooling device for use in a smoking oven wherein said device comprises or includes a heat sink, whereby in use smoke, from a smoke generator, for the smoking oven passes around the said heat sink before reaching the food to be smoked.

2. A cooling device as claimed in claim 1 wherein the said heat sink is placed in a smoke oven so as to absorb radiant heat from a smoke generator in said smoking oven.

3. A cooling device as claimed in any preceding claim wherein the said heat sink comprises at least one hollow member through which a fluid can be passed.

4. A cooling device as claimed in any preceding claim wherein the said heat sink is made from metal.

5. A cooling device as claimed in claim 3 in which the fluid is water.

6. A cooling device as claimed in claim 3 wherein the said heat sink comprises a radiator having a number of hollow members through which a fluid can be passed.

7. A cooling device as claimed in any of claims 3,4,5 and wherein the ability of the said heat sink to absorb heat can be altered by controlling the passage of a fluid through the said heat sink, the control of the passage of fluid being regulated by a temperature sensor in the smoke oven.

8. A cooling device substantially as hereinbefore described with reference to the accompanying drawings 3 and 4.

9. A process for smoking foods wherein said process comprises smoking foods in a smoking oven having a cooling device comprising or including a heat sink around which smoke is passed before it reaches the food to be smoked.

10. A process for smoking foods as claimed in claim 9 wherein said process comprises placing the said cooling device so as to absorb radiant heat from a smoke generator in the said smoking oven.

11. A process for smoking foods wherein the process includes the use of cooling device as claimed in any of claims 1-8.