EP1975517B1 - Method for controlling cooking processes in a steaming area - Google Patents

Description

Field of application and state of the art

The invention relates to a method for controlling cooking processes of a food in a cooking chamber of a Dampfgargerätes such as a steamer.

It is from the DE 103 27 861 A1 It is known to control a cooking appliance having a cooking space into which a food has been introduced by means of a sensor which detects a gas concentration in the cooking space. The gas concentration is observed over time, including by forming the first derivative.

From the DE 103 35 295 A1 Another method is known with which a moisture in a steam cooking appliance can be detected. In this case, however, an influence of the cooked food on the moisture is not detectable.

Task and solution

The invention has for its object to provide an aforementioned method with which problems of the prior art can be avoided and in particular a cooking process of food in a steam cooking appliance can be controlled by leaking from the food or gas.

This object is achieved by a method having the features of claim 1. Advantageous and preferred embodiments of the invention are the subject of the other claims and are explained in more detail below. The wording of the claims is expressed by express Reference made to the content of the description.

During the cooking process, during the cooking process, at least at times, in particular during a measuring phase, a concentration of a gas or moisture emerging from the food or in the cooking space is detected by a sensor such as a gas sensor over time. During the measurement phase, moisture or steam is not introduced into the steam cooking space during the operation of the steam cooking appliance, so that gas or moisture escaping from the food to be cooked can influence the sensor system sufficiently clearly or succinctly for reliable measurement. During this measuring phase, the sensor system or a sensor is evaluated or the measured values are evaluated over time for a specific time. During the measuring phase, the cooking end is determined for a given cooking process with fixed times of the supply of steam or the steam cooking operation by evaluating the sensors over time. In addition, at least the following step a) is performed. In step a), steam is introduced into the cooking chamber or the food to be cooked is steamed before the measuring phase during a vapor phase, as is the case with the cooking operation of the steam cooking appliance. After this vapor phase and again before the measuring phase, the steam supply is completed or is set during a ventilation phase, and by aeration of the cooking chamber, the concentration of steam or gas or moisture in the cooking chamber is at least significantly reduced. This can be a reduction by, for example, half, advantageously a strong reduction to values similar to the ambient air. In step b), steam is again introduced into the cooking chamber after the measuring phase during a vapor phase, or the food to be cooked is steamed, as it corresponds to the cooking mode of the steam cooking appliance. During this Vapor phase is omitted an evaluation of the sensor or it is no longer measured, as it is also advantageous in step a).

Thus, it is thus ensured in the context of the invention that during the measurement phase or before no steam has been introduced as part of the cooking operation in the cooking chamber, so that here the influence of the moisture of the food is relevant or can be reliably determined by the sensor , If, in the course of the selected cooking process, the food is then steamed after the measuring phase, for example when baking rolls, the cooking end is already determined beforehand by evaluating measurements during the measuring phase. At the same time, the introduction of steam is taken into consideration with regard to the end of cooking. Alternatively, due to the selected cooking process, the food is steamed before the measuring phase or steam in introduced the cooking chamber. Then, during the ventilation phase, this amount of steam or a vapor concentration is reduced to such an extent that steam or moisture emerging from the food to be cooked can be detected by the gas sensor. It is also possible to carry out both step a) and step b), ie to steam the food twice.

The fundamental determination of the end of cooking on the basis of the measured values of the sensors can be carried out as in the DE 10 2007 003 225 Such a measurement for detecting moisture is a direct measurement, especially if the moisture is measured directly.

Alternatively, a determination for a particular type of sensor that odgl no own gas sensor. carried out as in the DE 10 2005 042 698 Such a measurement for detecting the moisture is then an indirect moisture measurement or moisture detection, since the moisture is determined in another way and is not measured directly.

In an embodiment of the invention may at the end of the measurement phase or shortly before the end, especially if the Garende has already been determined, the Dampfgargerät continue to operate as before. This can be a kind of follow-up phase of the measurement phase, which is either additional or included. Again, with the gas sensor being measured, no steam should be supplied from the outside during this time. This type of follow-up time can be used in the event of a fault such as Opening a door to the cooking chamber, the measurement results of the sensors of the expected or previously determined course vary greatly or disturbed. The decay of this disorder can then be awaited or then a re-determination of the Garendes done. If, during this follow-up phase, the measurement results do not deviate significantly from the expected or predetermined course, then the cooking process can continue to run as previously determined until the end of cooking.

In an embodiment of the invention, the case that the vapor phase according to step b) is performed, so after the measurement phase once again steam is supplied, are taken into account in the control accordingly. The Garende can be brought about or shortened earlier, since with the steam is another energy input into the food. For this purpose, it may be provided that in a controller of the Dampfgargeräts the supplied amount of steam is known and the energy content of this steam is calculated, for example, also based on its measured temperature. In turn, the resulting energy input into the food can be calculated, which depends on the temperature conditions and / or the design conditions in the oven.

A vapor phase, in particular according to step a), can take 5 to 15 minutes. A measurement phase can take between 5 and 30 minutes. Advantageously, the measurement phase lasts so long or is carried out until a characteristic point or portion of the course of the measured values or the evaluation of the sensor is reached, due to which the cooking end can be calculated with sufficient accuracy. For this purpose, it may be provided that an operator enters the type of food in the steam cooking appliance in any way. Alternatively, the type of food can be determined from the evaluation of the sensor during the measurement phase, possibly taking into account further parameters, such as a type of vapor phase input by an operator, either at the beginning of the cooking process prior to the measuring phase and / or after the measuring phase. Also this is on the aforementioned DE 10 2007 003 225 pointed. In an embodiment of the invention, a gas sensor may be configured to directly measure a moisture in the cooking chamber or steam, which exits the food, for which the gas sensor is advantageously designed as a humidity sensor.

The Dampfgargerät may have a ventilation system for the cooking chamber, which makes it possible, depending on the progress of the cooking process, the air in the oven more or less quickly or more or less exchange with ambient air. This ventilation system may be controlled by a controller of the Dampfgargerätes in the context of the previously determined cooking process and possibly taking into account the determined during the measurement phase Garendes. It can, for example, with flaps, sliders or the like. be provided, which can be driven in particular by an electric motor.

During a vapor phase according to step a), the cooking chamber is advantageously closed or an air supply or ventilation of the cooking chamber, in particular with fresh air from the ambient air, is greatly reduced or suppressed. Here, substantially hot steam is supplied according to the steam cooking operation of the steam cooking appliance.

In an embodiment of the invention, the ventilation system of the cooking chamber can be open during the ventilation phase or the cooking chamber can be ventilated maximum. This results in the fastest possible removal of the steam from the cooking chamber or a reduction in the vapor content.

In yet a further embodiment of the invention advantageously takes place during the measurement phase, a low ventilation of the cooking chamber. These may be about 5% to 15% of a maximum possible ventilation, so that here during the measurement phase a certain, for the determination sufficiently large amount of moisture in the oven can occur, which over time by the sensor and especially by a gas sensor can be detected. For this purpose, the ventilation system of the cooking chamber or the Dampfgargerätes be open only to a small extent. Too much aeration would in turn allow too much moisture to escape from the cooking chamber and falsify a measurement or make it impossible.

During a possibly occurring before the measurement phase vapor phase according to step a), in which also a heating of the cooking chamber can take place, there is still no need for the detection of measured values. Since a determination of the end of cooking, which is ultimately a main object of the invention of the present application, can only take place on the basis of the evaluation of the curve for the moisture progression over time, there must be usable values for this, as they are not present, especially at the beginning of a cooking process. Thus, in order to obtain the necessary process information for determining the end of cooking, the sensor system should no longer be disturbed by external influences during the measurement phase, so that no change in the vapor content takes place, which indicates an incorrect state during the evaluation. Furthermore, in the cooking chamber due to a previously made steaming no too high concentration of vapor should be present, otherwise the amount of moisture exiting the food is too low and can no longer be sufficiently safe and accurate compared to an existing moisture quantity.

These and other features are apparent from the claims and from the description and drawings, wherein the individual features each individually or a plurality in the form of sub-combinations in one embodiment of the invention and on others Be realized areas and can represent advantageous and protectable versions for which protection is claimed here. The subdivision of the application into individual sections as well as intermediate headings does not restrict the general validity of the statements made thereunder.

Brief description of the drawings

Fig. 1

einen schematischen Seitenschnitt durch einen Dampfgarer mit einem Ansaugkanal, einem Wasservorrat, einer Heizung zur Dampferzeugung, einem Garraum und einem Belüftungssystem und

Fig. 2

ein Diagramm des Verlaufs der Feuchte über der Zeit mit fünf eingezeichneten Phasen des Betriebs.

Embodiments of the invention are shown schematically in the drawings and are explained in more detail below. In the drawings show:

Fig. 1

a schematic side section through a steamer with a suction duct, a water supply, a heater for steam generation, a cooking chamber and a ventilation system and

Fig. 2

a diagram of the course of the moisture over time with five phases of the operation.

Detailed description of the embodiments

In Fig. 1 a steam oven 11 is shown with a housing 12. The steamer 11 has a cooking chamber 13, in which a food support 14 is included along with cooked food 15 which is to be prepared in the steamer 11 and in the preparation of a vapor deposition is possible or even useful , Access to the cooking chamber 13 via a door 16, via which a Wrasenabzug 17 is provided. Inside the fume hood 17, a flap 23 is provided, which can be actuated by a control 36, for example, by an electric motor. The cooking chamber 13 is heated by a top heat radiator 19a and a bottom heat radiator 19b. These are controlled via the controller 36 together with an operating unit 37 according to a desired operator's default, such as temperature, water vapor composition and / or cooking time. The controller may include a memory, not shown, are stored in the information about certain programmed cooking processes.

The housing 12 has on its rear side access to an intake passage 21 through which fresh air can be brought into the cooking chamber 13. A flap 22 is provided to close the intake passage 21 can. The flaps 22 and 23 together form a ventilation system for the steamer 11, which is controlled by the controller 36. This will be explained in more detail below.

The intake passage 21 leads after the flap 22 to a water tank 30 as a water reservoir with water 31 over. In the water tank 30, a heater 32 is arranged to be controlled by the controller 36 from the water 31 to generate steam 34. Then, the steam 34 is brought by means of a fan 24 through the intake passage 21 into the cooking chamber 13. Also, the operation of the fan 24 is monitored by the controller 36, particularly as part of the ventilation system. Via a temperature sensor 38 and a humidity sensor 39, which forms the sensor system or is a part thereof, the operating conditions in the cooking chamber 13 can be monitored for influencing by the controller 36.

Via a further inner flap 27, which can be operated in cooperation with the flaps 22 and 23 of the ventilation system, a ventilation of the cooking chamber 13 and an air flow can be controlled. It can be supplied with open dampers 22 and 23 fresh air from the outside with normal water vapor content, for example, the so-called flushing of the cooking chamber 13 to flush out the steam 34 from the oven. When the inner flap 27 is open and the outer flap 22 is closed, the air in the cooking chamber 13 can be circulated. there the generation of additional steam 34 is also possible in the circulation operation, since here, too, the circulated air is passed through the intake passage 21 to the water tank 30.

In Fig. 2 a course of the moisture F over the time t is shown, which occurs for example when baking food such as bread or rolls. However, it should be noted that the course of the humidity F according to Fig. 2 Although it can be detected with the humidity sensor 39 in the cooking chamber 13. At the same time, however, this moisture profile can only be determined in this form if no additional moisture or steam is introduced through the steam cooking operation of the steam cooker 11. In this respect, the curve is according to Fig. 2 a more theoretical curve without external influences.

In the course of time t different phases of the moisture F are shown as temporal sections. During the first time or the vapor phase I, steam can be introduced into the steamer 11 during preparation of the food item 15, or the food item 15 can be steamed. This is expressed by the steam operation or the course of the curve D, which is shown thinner than the humidity F. Insofern, it is also understood that during the vapor phase I actually determined by the humidity sensor 39 in the cooking chamber 13 steam content or course of the Humidity differs from the theoretical humidity curve F.

During the vapor phase I, the flaps 22 and 23 are substantially closed or it is supplied with little air from the outside and may be made only by opening the inner flap 27 a kind of circulation. After completion of the vapor phase I is followed by a ventilation phase II. Here, the steam operation is stopped, so that no additional steam is introduced into the cooking chamber 13. During the ventilation phase II at least the flaps 22 and 23 of the ventilation system are open and the humidity in the cooking chamber 13 is by operation brought out of the fan 24, so the cooking chamber 13, so to speak flushed with fresh air. In this case, the opening width of the flaps 22 and 23 can be sensibly varied by the controller 36. Furthermore, either the moisture content in the cooking chamber 13 due to the previous vapor phase I can be reduced, for example to half, or the moisture can be removed as completely as possible or ambient air can be introduced into the cooking chamber 13.

After completion of the usually relatively short aeration phase II, the measurement phase III begins. For this purpose, the flaps 22 and 23 are largely closed to allow a small air supply or a low air exchange, for example, with 5% to 15% of a maximum ventilation level. Then, the operation of the steamer 11 corresponds to an operation of a normal oven, ie with at least the top heat 19a and / or the top heat 19b and without steam supply.

By reducing or removing the moisture from the vapor phase I in the cooking chamber 13, the amount of moisture corresponding to the moisture profile F according to FIG Fig. 2 emerges from the food 15 and prevails in the cooking chamber 13, play a more significant and important role. Thus, therefore, the moisture profile F can be detected by the humidity sensor 39. During the measurement phase III, which is carried out over a longer period of time, a method according to the DE 10 2007 003 225 be performed to regulate the cooking process of the food 15 in the steamer 11 or to determine an end of the cooking process. On the one hand, usually already before the start of the cooking process, the food to be cooked 15 is entered by an operator in the controller 36 of the cooking appliance, for example by means of the control unit 37. Furthermore, due to the course of the moisture F over time during the measurement phase III the end of the cooking can be predetermined or calculated. If this is done during the measurement phase III, a follow-up phase III 'is started. This follow-up phase III ', which is optional, is characterized in that it starts at a time when the cooking end is already predetermined. Furthermore, the measured values of the humidity sensor 39 and thus also the course of the humidity F over time are still recorded and evaluated. Should a fluctuation or disturbance of the measured values of the sensor 39 take place again during this time, the end of the cooking must be recalculated. However, this is already in the aforementioned DE 10 2007 003 225 described,

After the end of the follow-up phase III ', a second vapor phase IV can be carried out, which corresponds to the aforementioned step b). Here, as shown by the gradient for the vapor deposition D, once more steam is introduced into the cooking chamber for steaming the food 15. This can be done as described above. Again, it should be noted again that thus the moisture content in the cooking chamber 13 changes significantly compared to the moisture profile F of the food 15 alone. However, since the end of cooking has already been predetermined during the measurement phase III, and it has also been calculated that, and whether a second vapor phase IV follows again, this does not disturb. Finally, after the end of the second vapor phase IV, the food to be cooked 15 is considered finished and the cooking end is reached. It can be provided in various embodiments still to vent the cooking chamber 13, for example by re-opening the flaps 22 and 23 and operation of the fan 24. As can be seen from the foregoing description, it is advantageous if at least the flaps 22 and 23 of the ventilation system can be adjusted almost continuously for the most infinitely variable ventilation or ventilation of the cooking chamber thirteenth

With the invention can thus be advantageously achieved that not only in an oven, but also in a steamer 11 a provision the Garendes a Garguts 15 can be performed due to the time course of emerging from the food moisture F, although actually such a moisture determination in a steamer due to heavy steam, at least during certain times of the cooking process is not possible. The process is suitably suitable for a food to be cooked, which does not have to be permanently vaporized or at its intended preparation does not constantly high concentration of steam in the oven must be present, such as bread, rolls or other pasta, possibly even cake. Furthermore, it should be noted that during a ventilation phase II before the measurement phase III is not necessarily all steam or all moisture must be removed from the oven. However, the existing moisture is to be reduced to such an extent that the moisture exiting from the food to be cooked can be detected by the humidity sensor 39 sufficiently accurately in order to determine, based on the theoretical course Fig. 2 to determine the end of the cooking.

Claims (14)

1. Method for regulating a cooking process of a cooking product (15) in a cooking chamber (13) of a steam cooking apparatus (11) with a heating system (19a, 19b), preferably a steamer device, wherein during said cooking process at least periodically, during a measuring phase (III), a concentration of a gas passing out of said cooking product (15) or a moisture content (F) in said cooking chamber (13) with a cooking product (15) introduced is detected by a sensor system (39) over time (t), wherein during the measuring phase (III) an introduction of moisture or steam (34) into said cooking chamber (13) is ceased and the sensor system (39) is evaluated or the measured values thereof are evaluated with respect to time dependent behaviour over a given time, wherein for a predetermined cooking process with fixed times for supply of steam (34) on a basis of said evaluation of said sensor system (39) during the measuring phase (III) an end of cooking is determined, characterized in that further the following step is performed:

   a) prior to the measuring phase (III), during a steam phase (I), steam (34) is introduced into said cooking chamber (13) and the cooking product (15) is steamed, respectively, wherein following the steam phase (I) and prior to the measuring phase (III) during a ventilating phase (II), a steam supply is ended and the concentration of steam (34) and moisture, respectively, in the cooking chamber (13) are at least significantly reduced by ventilation.
2. Method according to claim 1, characterized in that further the following step is performed:

   b) following the measuring phase (III) during a steam phase (IV) steam (34) is introduced into the cooking chamber (13) and the cooking product (15) is steamed, respectively, wherein during the steam phase an evaluation of said sensor system (39) is ceased.
3. Method according to claim 1 or 2, characterized in that near an end of the measuring phase (III), in particular after completion of determining the end of cooking, the so far continued operation of the steam cooking apparatus (11) remains unchanged, wherein during this time no steam (34) is supplied.
4. Method according to claim 3, characterized in that in case that through a fault or disturbance said measured results of said sensor system (39) differ greatly or are disturbed as compared with said expected or predetermined pattern, subsiding of the disturbance is awaited and then determining the end of cooking is repeated.
5. Method according to any of the preceding claims 2 to 4, characterized in that in case that said steam phase (IV) is performed according to step b), the supply of steam (34) is considered in the control (36) and an end of cooking is caused or effected earlier.
6. Method according to claim 5, characterized in that the supplied amount of steam (34) is known and an energy content is calculated therefrom and consequently said resulting energy introduction into said cooking product (15) is calculated as a function of temperature conditions and/or constructional conditions in the cooking chamber (13).
7. Method according to any of the preceding claims 2 to 6, characterized in that the steps a) and b) are performed both with a first steam phase (I) prior to said measuring phase (III) and with a second steam phase (IV) following said measuring phase (III).
8. Method according to any of the preceding claims, characterized in that during the ventilating phase (II) the steam content in the cooking chamber (13) is reduced to less than a half thereof, wherein preferably a complete air exchange is obtained and steam (34) and moisture, respectively, are flushed out.
9. Method according to any of the preceding claims 2 to 7, characterized in that the steam phase (I, IV) according to step a) and/or step b) takes 5 to 15 minutes.
10. Method according to any of the preceding claims, characterized in that during the measuring phase (III) the measured results of said sensor system (39) are evaluated until a characteristic point or portion is reached on basis of which said end of cooking can be adequately precisely calculated.
11. Method according to any of the preceding claims 2 to 7, 9, characterized in that during the steam phase (I, IV) of step a) and/or step b) the cooking chamber (13) remains closed and an air supply or ventilation of said cooking chamber is greatly reduced or suppressed.
12. Method according to any of the preceding claims, characterized in that during the ventilating phase (II) a ventilation system of the cooking chamber (13) is opened, preferably opened to a maximum.
13. Method according to any of the preceding claims, characterized in that during the measuring phase (III) there is a limited ventilation of the cooking chamber (13), preferably approximately 5% to 15% of a maximum possible ventilation, wherein in particular a ventilation system (22, 23) of the cooking chamber is opened to not more than a small extent.
14. Method according to any of the preceding claims, characterized in that the sensor system is used to measure moisture in the cooking chamber (13) and the sensor system includes a moisture sensor (39), respectively.

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