HK1221005B - Method for cooking a cooking product, and cooking device - Google Patents

Description

Method for cooking food and cooking device

Technical Field

The invention relates to a method for cooking food, in particular with steam, and to a correspondingly designed cooking device.

Background

EP723115 a2 describes a method for cooking meat, in which a cooking chamber is heated with hot air during a food temperature conditioning phase in the following manner: the food temperature follows a desired food temperature function that depends on time. In this way, a certain food temperature (core temperature) can be reached at a desired time. However, it has been found that by following this procedure it takes a relatively long time for the food to cook, since the slope of the desired food temperature function, which is time dependent, must not be chosen too steep in order to avoid local overheating at the meat surface.

EP2537418 a1 describes a method for cooking food (e.g. meat) in a cooking apparatus with steam, wherein the food is sealed in a bag. The cooking chamber is heated with steam, wherein the food temperature is measured by a food temperature measuring probe and regulated by a regulating circuit on a gradually rising slope until the food temperature reaches the final food temperature. While monitoring the cooking chamber temperature to avoid exceeding limits. Followed by an optional high temperature stage with elevated temperature. By this method the food can be cooked quickly and in a gentle manner.

Although cooking with steam is considered gentle, the use of a bag to seal the food is a limitation in the usability of the oven. Therefore, it is an object to develop a gentle steam cooking method that does not rely on sealing food in a bag and still allows for gentle cooking of food.

Disclosure of Invention

In a method for operating an oven according to the invention, food is inserted into its cooking chamber and the cooking chamber temperature in the cooking chamber is controlled in the following manner: the food temperature follows a time-dependent desired food temperature function, wherein the desired food temperature function has at least a first phase and a second phase following the first phase and has a steeper gradient in the first phase than in the second phase.

For this purpose, the cooking chamber is preferably heated by steam insertion in doses (dised) (optionally also by using further heating means), with the result that a more efficient heat input in the food is made possible without the need to use very high temperatures in the cooking chamber.

In a further preferred version of the method, the food is heated in a cooking chamber without a steam isolation bag.

Preferably, the desired food temperature function is selected such that it increases over time to the final food temperature such that the desired core temperature is reached at the end of the food temperature conditioning phase. In a preferred version of the invention, the desired function is thus an approximation to an exponential process of the food temperature with a steep temperature rise during the first phase and a gradual convergence to the final food temperature during the second phase. In a particularly preferred version of the invention, it is desired that the food temperature function therefore increases monotonically, in particular strictly monotonically, e.g. linearly, during a first and a second phase, wherein the second phase immediately follows the first phase. The transition between the first stage and the second stage may be located in a food temperature interval between 10 ℃ and 30 ℃ below the final food temperature.

The duration or end time of cooking when the food should be prepared for completion can be preset. Preferably, the maximum cooking duration is below 3 hours, which corresponds to a significantly shorter duration compared to a typical soft cooking with steam.

Preferably, the first and second stages having a time dependent desired food temperature function are preceded by a pre-heating stage. This pre-heating stage brings the food from any initial temperature to a pre-programmed food temperature. It is preferably located in the interval between 20 ℃ and 30 ℃, particularly preferably in the interval between 23 ℃ and 27 ℃. Thus, the food is brought to an accurately determined temperature, regardless of any initial temperature (which may vary, for example, between a freezing temperature and room temperature), before the start of the first phase of the time-dependent desired food temperature function.

Advantageously, it should be noted that the cooking chamber temperature never rises too much. In a preferred embodiment, this is achieved by controlling the cooking chamber temperature in the following manner: which exceeds the final food temperature by a maximum of 30 c, in particular by a maximum of 15 c, in particular by a maximum of 10 c. Alternatively or additionally, the cooking chamber temperature may be controlled in the following manner: which does not exceed a predefined fixed limit temperature, wherein the fixed limit temperature is less than 105 deg.c. During the preheating phase, the cooking chamber temperature is preferably limited to a range between 60 ℃ and 80 ℃.

Once the respective limit temperature is reached, the temperature is lowered below the desired food temperature function to ensure that the cooking chamber temperature does not rise further.

The invention is particularly suitable for cooking meat (wherein fish is also counted as meat in this context), since in this case the cooking process can be terminated after the desired core temperature has been reached. In this case, the final food temperature is selected according to the generally known favorable core temperature of the particular meat. However, the method can also be used for other types of food, such as vegetables.

Brief Description of Drawings

Further embodiments, advantages and applications of the invention are derived from the dependent claims and from the following description which is now made with reference to the drawings. Thereby illustrated in the following figures:

fig. 1 is the most important components of a cooking apparatus; and

fig. 2 is a qualitative process of the food temperature TGG, the cooking chamber temperature TGR, and the desired food temperature TGGs.

Detailed Description

The cooking device according to fig. 1 has a cooking chamber 1 for receiving food 2, for example on a metal plate or grid 3. Furthermore, the apparatus has a controller 4 and a steam generator 5. The steam generator 5 serves to heat the cooking chamber 1 with steam. The steam generator 5 may utilize additional hot air to generate superheated steam at temperatures above 100 ℃.

Other means for heating the cooking chamber may also be present, for example, an electrical resistance heater. The cooking device is preferably an oven with steam cooking function, however it may also be a pure steam cooking device, for example.

The controller 4 comprises means 6 or the like for generating a desired food temperature function, which means a time-dependent desired value TGGs of the food temperature TGG. The means 6 may be, for example, memory and computing means which generate such functions in a known manner. Preferably, the means 6 are formed such that the desired food temperature function TGGS comprises a first phase and an immediately subsequent second phase, wherein the food temperature adjustment phase of the device is first increased and monotonically increased (in particular strictly monotonically increased) from a starting value temperature to an intermediate temperature lying, for example, 25 ℃ below the final food temperature TGGE, and subsequently increased with a flatter gradient, but still monotonically increased (in particular strictly monotonically increased), up to the final food temperature TGGE. The gradients of the first and second stages may be set as follows: this final food temperature TGGE is reached within a time period, which may be set by a user via an input unit (not shown) of the oven. This period of time may be 3 hours or less.

Furthermore, the controller 4 comprises a first regulator 7 and a second regulator 8, each of which can compare the current value with the desired value and generate a control variable in such a way that the current value is adapted to the desired value.

The first regulator 7 is connected to a food temperature measuring probe 9. The food temperature measuring probe 9 measures the food temperature TGG, the so-called core temperature, of the food 2 substantially in the middle. The desired value TGGS of the temperature of the food is supplied by the device 6 as desired value to the regulator 7. The regulator 7 compares the food temperature TGG with its desired value TGGs and generates from this comparison a desired cooking vessel temperature TGRS, which is selected in such a way that the food temperature TGG tends to reach its desired value TGGs.

The second regulator 8 is connected to a cooking chamber temperature measurement probe 10. The cooking chamber temperature measuring probe 10 measures a cooking chamber temperature TGR. The second regulator receives the desired value TGGS from the first regulator, compares it with the current cooking chamber temperature TGR and generates from this comparison a control signal for the steam generator 5. This control signal controls the steam generation and is selected in the following way: the cooking chamber temperature TGR tends to reach its desired value TGRs. If the device is controlled based on a preset cooking chamber temperature TGR (e.g. during a pre-heating phase as further described), only this part of the control is necessary.

The regulators 7 and/or 8 or generally the controller 4 are advantageously formed in the following manner: the cooking chamber temperature TGR does not exceed the limit temperature TLIM 105 ℃. In this way, thermal damage to the food surface can be avoided.

Hereinafter, a cooking method performed with the above cooking apparatus will be described. It is however noted that the described cooking method corresponds to only one of a plurality of possible operating modes of the cooking apparatus. The cooking apparatus is also generally capable of cooking food by employing other conventional methods.

In the mode of operation described herein, the food temperature measurement probe 9 is first inserted into the food 2. In the embodiment according to fig. 1, the measuring probe 9 has been inserted directly into the food 2. No steam barrier bag is used (which protects the food from the hot steam in the cooking chamber and is described in e.g. EP2537418 a 1).

The food 2 provided with the measuring probe 9 is then inserted into the cooking chamber 1 and the cooking procedure is started. The subsequent steps of this cooking program run automatically and are controlled by the controller 4. The course of the cooking temperature TGG, the desired food temperature TGGs, and the cooking chamber temperature TGR during this cooking procedure is shown in fig. 2. Thus, the food temperature TGG is illustrated with a dashed line covering a continuous drawn line of desired food temperature values TGGS. The upper line in fig. 2 represents the cooking chamber temperature with two different processes TGR (1), TGR (2).

First, the steam generator 5 is activated so that the cooking chamber temperature TGR starts to rise. (optionally, the cooking chamber may also be heated by, for example, an electrical resistance heater or another suitable heating device). The cooking program illustrated in fig. 2 begins at time t0, at which time the cooking chamber temperature is 60 ℃.

During an optional first (pre) heating phase for warming (temper) the food in a gentle manner and to compensate for the different initial temperatures, the food is heated while measuring the temperature of the food. This phase ends at time t1 when the food has a selectable, programmable food temperature, such as 20 ℃.

During a further optional second phase, which follows the first phase, the cooking of larger food pieces is accelerated. The degree of acceleration can be assessed by the course of the food temperature TGG during the first phase.

For example, the cooking chamber temperature in the second phase may be derived from the duration of the first phase, wherein the first cooking chamber temperature TGR (1) at a duration not longer than the preset duration t1 is selected. In this example, this temperature is an initial temperature of 60 ℃. If the duration is longer than the preset duration t1, a second cooking chamber temperature TGR (2) may be selected. In this example, this temperature is constantly 70 ℃, as shown in fig. 2 (after heating), in order to accelerate the heating of the food.

If the desired food temperature is still not reached after reaching the preset maximum duration tmax of the first phase, the first phase may be stopped and a subsequent second phase with an even higher preset temperature, e.g. 80 c, may be started. This process is not shown in fig. 2.

In an alternative example, three temperature settings of 60 ℃, 70 ℃ or 80 ℃ for the second stage may also be derived from the gradient of the food temperature during the first heating stage.

During an optional second heating stage, the food is heated with a selected cooking chamber temperature of 60 ℃, 70 ℃ or 80 ℃ up to a (second) selectable food temperature, e.g. 25 ℃. If this temperature is not reached after the preset time t2, the cooking process is stopped by displaying an error message to the user.

During the first two heating phases, the temperature increase is determined by the cooking chamber temperature. The heating phase after these two optional pre-heating phases is controlled by a preset desired food temperature function TGGS, i.e. a time dependent desired value TGGS of the food temperature TGG. In principle, the individual heating phases can be controlled by a preset TGGS function, but such control can increase the cooking chamber temperature TGR to a higher level than desired.

The desired value TGGS describes that during the heating phase, as shown in fig. 2, there is first a steeply increasing desired value followed by a flatter phase ending at the final food temperature TGGE is reached. The desired food temperature function shown in fig. 2 can be considered as an exponential process of the type TGGE (1-exp (-kt)), where k is a time constant that depends on the desired cooking time, which is approximated with two linear segments. When the curve initially rises more steeply, the cooking chamber temperature TGR is avoided to have a very high value at the end of the heating phase. On the other hand, overshoots (overshoots) in the food temperature, especially in the case of small food pieces, can be avoided better than simple linear processes, as described for example in EP2537418 a 1.

The gradient of the steeper first phase of the desired food temperature function may be selected in the following manner: maximum heat insertion into the core of the food is possible without affecting the quality of the final product of the cooking process. For meat, the gradient is in the range from about 0.7 ℃/minute to 1.5 ℃/minute, and particularly in the range from about 1.1 ℃/minute to 1.3 ℃/minute.

The second phase starts at time T3a, at which time the food temperature is increased to a temperature which has a defined temperature difference Δ T from the final food temperature TGGE. The difference deltat may for example be chosen in the range between 10 and 30 c or between 15 and 30 c below the final food temperature, preferably in the range between 23 and 27 c below the final food temperature.

The gradient of the second stage may then be determined by the relationship between the temperature Δ T and the remaining cooking time T3 b-T3 a.

During this second phase, the food is preferably gently brought close to the final food temperature, preferably without overshoot of the food temperature and close to the final food temperature TGGE. In this way, subsequent cooking of the food after cooking is terminated is limited.

As shown in fig. 2, during the whole phase, the protective conditions ensure that the temperature of the cooking chamber is limited to a maximum temperature TLIM of 105 ℃. This temperature can be reached and possibly even exceeded by the use of superheated steam.

The described method is particularly suitable for meat, as initially mentioned. But the method can also be applied to the example of vegetables. In this case, the cooking chamber temperature should be maintained at the desired final food temperature TGGE for a certain time at the end of the food temperature adjustment phase.

If a different crust is desired, the food may be baked in, for example, a pan.

While preferred embodiments of the present invention have been described in the present application, it is expressly intended that the present invention not be limited to these preferred embodiments and may be practiced otherwise than as specifically described within the scope of the claims that follow.

Claims (16)

1. Method for cooking food (2) in a cooking apparatus having a cooking chamber (1) during a cooking period, wherein a food Temperature (TGG) is measured and wherein a cooking chamber Temperature (TGR) outside the food (2) in the cooking chamber is controlled at least during a food temperature adjustment phase of the cooking period in the following manner: the food Temperature (TGG) follows a time dependent desired food temperature function, characterized in that: the food (2) is inserted into the cooking chamber (1) and the desired food temperature function (TGGS) comprises at least two phases with different gradients, wherein a second phase after a first phase has a lower gradient than the first phase.

2. Method according to claim 1, characterized in that the cooking chamber (1) is at least partially heated by hot steam.

3. Method according to claim 1 or 2, characterized in that the food (2) is heated in the cooking chamber without a steam isolation bag.

4. Method according to claim 1 or 2, characterized in that the desired food temperature function (TGGS) is selected such that the temperatures of the first and second phases monotonically increase up to a final food Temperature (TGGE).

5. The method of claim 4, wherein the first stage and the second stage are linear and the first stage transitions to the second stage at a temperature selected from a range between 10 ℃ and 30 ℃ below the final food Temperature (TGGE).

6. The method of claim 1 or 2, wherein for meat the gradient averages between at least 0.7 ℃/minute and 1.5 ℃/minute during the first stage.

7. Method according to claim 1 or 2, wherein the gradient in the second phase is determined by the temperature difference between the food temperature at the end of the first phase and the final food Temperature (TGGE) and the remaining cooking time at the end of the first phase.

8. Method according to claim 1 or 2, characterized by a pre-heating phase preceding the desired food temperature function (TGGS) having at least two phases, wherein the pre-heating phase brings the food (2) to the determined temperature at the beginning of the first phase.

9. The method of claim 8, wherein the cooking chamber Temperature (TGR) during the preheating phase is limited to a range between 60 ℃ and 80 ℃.

10. Method according to claim 8, characterized in that the food Temperature (TGG) is measured during the pre-heating phase and parameters for determining subsequent cooking chamber temperatures (TGR (1), TGR (2)) are derived from the course of the food temperature.

11. Cooking device adapted to perform the method according to one of the preceding claims, having a cooking chamber (1) for receiving food (2),

a food temperature measuring probe (9) for measuring a food Temperature (TGG) of the food (2), and

a controller (4) designed to control a cooking chamber Temperature (TGR) in the cooking chamber (1) during the food thermoregulation phase such that the food Temperature (TGG) of the food (2) follows a time dependent desired food temperature function (TGGS) and such that the desired food temperature function (TGGS) has at least two phases with different gradients, wherein a second phase following a first phase has a lower gradient than the first phase.

12. Cooking device according to claim 11, characterized by a steam generator (5) for heating the cooking chamber (1) with steam.

13. Cooking device according to claim 11 or 12, characterized in that the food temperature measuring probe (9) for measuring the food Temperature (TGG) of the food (2) is designed without a steam insulated bag.

14. Cooking apparatus according to claim 11 or 12, characterised in that the controller is designed in the following way: the gradient of the desired food temperature function (TGGS) in the first stage is on average at least between 0.7 ℃/min and 1.5 ℃/min.

15. Cooking apparatus according to claim 11 or 12, characterised in that the controller (4) is designed in the following way: the controller determines a gradient in the second phase by a temperature difference between the food temperature and a final food Temperature (TGGE) at the end of the first phase and a remaining cooking time at the end of the first phase.

16. Cooking apparatus according to claim 11 or 12, characterised in that the controller (4) is designed in the following way: the controller measures the food Temperature (TGG) during a heating phase preceding the desired food temperature adjustment phase having at least the first and second phases and the controller determines a parameter for adjusting a subsequent cooking chamber Temperature (TGR) according to a course of the food temperature.