DE20004048U1 - Device for electronically controlled low-temperature cooking with integrated rapid cooling - Google Patents

Description

Device for electronically controlled low-temperature cooking with integrated rapid cooling

The invention describes a device that can be used in households, restaurant kitchens or large kitchens. It is possible to carry out various processes for temporary food storage and subsequent preparation, such as cooking, frying, baking and cooling, in a time-controlled manner, whereby additional technical measures can be used to speed up the process steps mentioned and to preserve and improve taste. The invention does not represent a combination of known individual components of conventional kitchen technology, but it is shown that the suggestions made as a whole lead to new effects.

For the automatic treatment of foodstuffs that require prior storage or are subjected to certain thermal processing processes, there are already sophisticated technical solutions that have been more or less described and have so far been partially applied.

DE-OS 195 14 178.4 proposes that after a cooling process with a time-dependent switch to heating and cooking, measures should be taken to prevent undesirable drying out, e.g. of food, by targeted exposure to moisture. Further proposals are made for the treatment of food with a rapid temperature rise of 40 to 50°C during cooling followed by cold storage.

DE-OS 196 14 309 offers a significant improvement to the solution described above. By deliberately dividing the otherwise available space (baking or roasting oven) into at least three thermally insulated compartments, it is possible to prepare animal or vegetable products for human consumption independently of one another and, if necessary, in parallel. Using a closed system of two channels for hot and cold air that can be switched on independently of one another for each compartment, meals can be prepared either in a time-controlled manner or according to

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Prepared raw materials or already cooked meals can be stored for a period of time that is acceptable from a food hygiene perspective, during which time reheating can be achieved by redirecting the air currents. However, the supply of air currents to the above-described compartments is rather complicated and can be achieved using controllable solenoid valves.

The German utility model application 297 06 351.0 can be seen as a refinement of the technology of low-temperature cooking and the removal of the fumes that are nevertheless produced. In the cooking/baking chamber, there is an integrated extractor hood on the top of the chamber, where a fan with suction and pressure nozzles sucks the light from the cooking process and directs it into a pipe coil on the back of the oven, which carries out a heat exchange with the ambient air. The frying and cooking fumes that precipitate in this are then collected in a collecting tray located below the cooking chamber. The extracted moisture-laden air mixture is cleaned of salt or fat particles using adapted activated carbon filters. The moisture that occurs during baking and is not needed is discharged into the environment by operating a flap in the extractor hood.

The solution according to the invention, which is explained in the description presented here, is partly based on DE-OS 196 14 3U9, but goes beyond it in terms of process technology and also in terms of the apparatus and perfects it.

In accordance with the task, the new facility should be able to be used universally, adapted to the respective location, which will save the space that would otherwise be required for individual devices that have previously only existed in this form.
Other effects that can be achieved in the sense of the task include in particular:

- Energy, time and drinking water savings

- Compliance with increasingly strict hygiene regulations

- Reduction of investment expenditure, e.g. when redesigning a kitchen in conjunction with optimal use of existing work space

- technologically improved manufacturing methods, whereby the service life of the high-quality device (operating characteristics) is also given greater importance.

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In the further description of the application model, a clear presentation of the device according to the invention is given, with parallel process steps being explained.

The basic equipment of the device according to the invention includes a conventional electric oven, which is designed as a circulating air oven. It essentially consists of the combined cooling and cooking chamber or baking chamber, a cooling unit arranged under the said chamber, a closed channel circuit with an inlet and outlet opening in the cooling and cooking chamber or baking chamber (tube) and variously arranged heating coils as well as switchable high-speed fans for the purpose of rapid cooling or rapid fermentation. In addition, there is a vent shaft in the upper part of the tube, which fulfills its function primarily in the cooling and baking treatment stages.

The tube is a state-of-the-art insulated room in which cooling processes can take place using the cooling unit or cooking and baking processes can take place using a time-controlled electric heater. This tube contains grates that can be inserted at different heights and a heated base plate for contact heating of containers filled with saturation or active ingredient additives. ■..·■·.

To generate the cooking and baking heat, two heating coils are arranged in the upper part of the tube, which can be switched electrically one after the other for the heating and cooking period in order to reach different temperatures, depending on when the food stored in the tube is to be prepared: In parallel, it is planned that another heating coil, which is arranged in the base plate of the tube, can be switched on with bottom heat.

In addition to the fan in the rear wall of the tube, which ensures "normal" air circulation, there are 2 or more high-speed fans in the rear wall of the tube, which can be electronically operated, particularly in the "rapid fermentation" and "rapid cooling" phases, which advantageously allows the cold or warm air to be transferred more quickly to the core of the product to be cooked. This ensures that meat products, for example, are heated quickly in such a way that the pores close and mass loss during cooking is kept to a minimum. The cooking chamber temperature sensor and core temperature sensor, the latter being located like a probe inside the food to be prepared, switch off a lower heating level and in particular the additional fans when the cooking temperature is reached, whereby the cooking process in the low-temperature cooking range between 75° C and 100° C continues until the

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The cooking process can continue until the cooking is complete. After this, all energy supply is stopped and, if necessary, the cooling (quick cooling) of the meat products or a meal is initiated within a period of around 4 hours that is safe from a food hygiene perspective.

The air currents generated during snow cooling are conveyed by means of a closed duct system, with inlets and outlets in the tube at the bottom, on one side on the left, and at the top of the tube, on the right. After the temperature (core temperature) has dropped to around 5° C, the cooling phase is continued with all fans switched off. The contact with the ambient temperature or outside air, which is necessary in this situation, as is the case with baking and roasting, is established by means of another exhaust air duct located in the upper part of the tube. It is necessary that the temperature gradient between the environment and the cooling/cooking chamber (tube) is not balanced out. For this purpose, there is also a heating coil with a low heat output in the upper part of the tube, near the exhaust air duct, which only needs to be switched on in a controlled manner when the outside temperature is lower than that measured in the tube. Such a configuration is conceivable, for example, in unheated side rooms or storage rooms.

As a further improvement in the taste of products to be cooked, a technical measure is proposed in which a water reservoir with a capacity of several liters is provided on the rear wall (outside), whereby the required water is passed on to a modified narrow evaporation tray, known as a bain-marie, on the floor and inside of the tube. A float device coupled to the bain-marie (evaporation tray) ensures that the liquid level is always around 1/21, whereby in addition to the effect of not drying out a roast, aromas introduced into the liquid have a flavor-enhancing and digestible effect as it precipitates on the same. The circulating air fan can be operated while the aroma air is being humidified using the bain-marie (evaporation tray). The float control can be electronically adjusted.

The combination of alternating cooling and heating makes new processes in the food industry possible in the cooking and cooling processes in one device. In addition to the fermentation process, important preparatory and post-processing steps can also be carried out.

The invention will be explained in more detail using an embodiment.
Figure 1 shows a schematic representation of the device according to the invention.

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The reference symbols used therein have the following meaning:

I-tube

1 - Heating coil

3 - Cooking spiral 1

4 - Cooking spiral 2
f - recirculation fan

(< - high speed fans
7 - Garraiimtemperature filler
K - Nuclear Operation Guide
9 - Inlet opening
IU - outlet)ffiuing

11 - Drainage channel

12 - Heating coil

13 - Water reservoir at the back (indicated)
1 A - supply line for water

1 5 - Baininarie evaporation dish

16 - Cooling unit with Lüder

17 - Slide-in grids

18 - Menu setting

A conventional electric oven with built-in circulating ventilation has a cooking, baking, grilling or cooling chamber, the tube 1, which is insulated against heat or cold loss. In addition to the circulating fan 5 positioned centrally in the rear wall of the tube 1, there are further symmetrically arranged high-speed fans 6 of small diameter, which are electronically controlled and can be optionally switched on in the "quick cooling" and "quick fermentation" heating stages. In the upper part of the tube I there is, in order to achieve a rapid heating temperature, firstly the heating coil 2 with a power of up to 3 kW and, secondly, the cooking coil 1 [3] which is to be put into operation for the duration of the cooking. In the immediate vicinity of these, an exhaust duct 11 is provided above, at the opening of which the heating coil 12 is arranged. The latter only has a heating power which does not exceed 0.3 kW.

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The fermentation spiral 1 [3] and the fermentation spiral 2 [4] are designed to provide the upper heat and the lower heat and achieve a maximum heating output of approx. 1.5 kW.

The processes of rapid cooking, cooking and rapid cooling are monitored by a cooking chamber temperature sensor 7 positioned centrally in the oven, which is closely related to the core temperature sensor 8. The core temperature sensor 8 is a flexible probe that monitors the ripening process, for example that of a roast, inside the meat during cooking.
After the meat dishes have been cooked, the temperature can be regulated to storage temperatures within 4 hours and the high-speed fans 6 are put into operation again for this purpose. The corresponding cooling is developed by a cooling unit 16 which is housed below the tube 1, in a space which is also insulated. The temperature is gradually reduced via a cooling circuit which has an inlet 9 and an outlet 10 in the tube 1.

Furthermore, there is a water reservoir 13 on the outer rear wall of the stove, which is connected to a modified bain-marie evaporation tray via the supply line 14. The latter is located on the rear side of the bottom of the tube 1 and is supplied with a liquid level of approx. 1/2 liter by means of a float switch (not shown in detail). The advantageous use of these details is that meat dishes can be prevented from drying out and, if necessary, the taste can be improved by adding flavorings.

Claims (7)

1. Device for electronically controlled low-temperature cooking with integrated rapid cooling, consisting of a substantially modified circulating air oven, characterized in that the cooling and cooking chamber, the tube ( 1 ) and the chamber with the cooling unit ( 16 ) are insulated against cold and heat loss, wherein in the upper region of the tube ( 1 ) two heating coils ( 2 , 3 ) for the top heat, which can be controlled electrically for rapid cooking and cooking, and in the region of the base a heating coil ( 4 ) for the bottom heat are arranged and in addition to the circulating air fan ( 5 ) in the rear wall of the tube ( 1 ) there are further high-speed fans ( 6 ) which can be switched on temporarily during the rapid cooking/rapid cooling period, and a single-channel system running over the tube ( 1 ) with diametrically opposed inlet and outlet openings ( 9 , 10 ) is available for rapid cooling, wherein in the upper Part of the tube ( 1 ) an exhaust duct ( 11 ) is attached for the baking period. 2. Device for electronically controlled low-temperature cooking according to claim 1, characterized in that a cooking chamber and a core temperature sensor ( 7 , 8 ) in conjunction with the time-controlled electronics have contact with the thermal processes inside the tube ( 1 ). 3. Device for electronically controlled low-temperature cooking according to claim 1, characterized in that a heating coil ( 12 ) is additionally attached to the exhaust air duct ( 11 ). 4. Device for electronically controlled low-temperature cooking according to claim 1, characterized in that a bain-marie evaporation tray with aromas and water ( 15 ) is placed inside the tube ( 1 ), which is located on the floor in the rear area, and is connected via the supply line ( 14 ) to a water reservoir ( 13 ) which is attached to the outer rear of the cooker. 5. Device for electronically controlled low-temperature cooking according to claim 4, characterized in that the liquid level of the bain-marie evaporation tray ( 15 ) is float-controlled with electronic readjustment. 6. Device for electronically controlled low-temperature cooking according to claims 1, 2 and 4, characterized in that a menu setting ( 18 ) is additionally provided in the control panel of the device according to the invention. 7. Device for electronically controlled low-temperature cooking according to claims 1 and 6, characterized in that slide-in grids ( 17 ) enable the tube ( 1 ) to be divided up for simultaneous cooking processes.