METHOD FOR BAKING A DESSERT USING STEAM DESCRIPTION OF THE INVENTION The invention relates to a method for baking a dessert in an automated domestic oven using steam. Some types of desserts, especially delicate desserts such as créme brulee and cheesecakes, benefit from steam baking. The introduction of steam into the baking cavity adds moisture to the dessert and decreases the cooking speed of the dessert to facilitate uniform heating and cooking. The steam acts as an insulator or a buffer to facilitate good heat transfer throughout the dessert. As a result, the steam prevents the outer part of the dessert from falling and the inside of the dessert cooking insufficiently. Ovens that are found in most homes today are usually not equipped with a system that introduces steam into the oven cavity during the dessert baking process. In response, bakers have developed various home remedies to supply steam inside a furnace cavity. Such remedies include surrounding the dessert with a water bath, placing a pan in the oven before preheating and filling the pan with water when the dessert is placed in the oven, spraying water on the walls of the oven with a spray bottle after placing Dessert in the oven, throw ice cubes in the bottom of the oven to create steam. Another method involves forming perforations in the bottom of an aluminum cupcake container, placing the container on the bottom grill of the oven, filling the aluminum container with boiling water about one minute before putting the dessert in the oven so that the water drip on the bottom of the oven and get to create steam, and remove the aluminum container after approximately five to ten minutes. Although home remedies are successful in introducing steam into the oven cavity, they are relatively unpredictable and inconvenient. Water or ice introduced into the oven cavity vaporizes to create steam, which fills the oven cavity. The amount of steam in the oven can be quantified as a relative humidity, and the degree of relative humidity affects the dessert's baking process. Because water or ice is introduced manually, the amount of steam and therefore the relative humidity are not regulated and in addition, the relative humidity is not regulated as a function of the cooking cycle time. As a result, the relative humidity in the oven cavity may differ from the ideal conditions at various times during the baking process. In addition, some of the methods may require the baker to periodically check the dessert and add more water or ice to the cavity if necessary. This process can be inconvenient for a baker who wishes to leave the dessert unattended after placing the dessert in the oven. Some modern ovens of greater prestige incorporate an automated steam generation system that can be used to bake the dessert. These ovens eliminate the need for a baker to manually enter water or ice into the cavity. A method for baking a dessert using steam according to an embodiment of the invention during a cooking cycle in an automated domestic oven with a cooking cavity, a heating system for heating the cooking cavity, and a steam system for introducing steam within the cooking cavity comprises a first heating step comprising preheating the cooking cavity at a first temperature at a first heating rate, a second heating step comprising preheating the cooking cavity from the first temperature to a second temperature at a second heating speed lower than the first heating rate; and introduce steam inside of the cooking cavity. The first temperature can be at least the boiling point of water. The first heating step may comprise a differential heating of the cooking cavity at a first temperature. The first heating rate can be about 19.4 ° C / minute (35 ° F / minute). The second heating step may comprise uniformly heating the cooking cavity to a second temperature. The second heating rate can be about 3.3 ° C / minute (6 ° F / minute). The second temperature can be a temperature just below the desired minimum steam cooking temperature. The desired minimum steam cooking temperature can be approximately 121.11 ° C (250 ° F). The second heating step may comprise reducing a duty cycle of at least one upper heating element and a lower heating element of the heating system to reach the second heating rate. The duty cycle of the upper heating element may be less than the duty cycle of the lower heating element. The introduction of steam can occur during the second heating step. According to a modality, the introduction of steam does not occur during the first heating step. The method may further comprise a third heating step for heating the cooking cavity to a third temperature from the second temperature. The third temperature can be entered by a user inside a control panel of the oven. The cooking cavity can be maintained at a predetermined relative humidity during the third heating step. The predetermined relative humidity can be a maximum relative humidity for the furnace. The method may further comprise operating a convection fan of the oven to circulate air in the cooking cavity during at least one of the first heating step, the second heating step and the third heating step. The method may further comprise stopping the operation of the convection fan after the third heating step. The convection fan may remain off for the remainder of the cooking cycle after the third heating step. The method may further comprise maintaining the cooking cavity at a third temperature until the end of the cooking cycle. The method may further comprise introducing a decreasing amount of steam into the cooking cavity after maintaining the predetermined relative humidity. The method may further comprise finishing the introduction of the decreasing amount of steam prior to the end of the cooking cycle.
The dessert may be in the cooking cavity during the first and second heating steps. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: Figure 1 is a perspective view of an exemplary automatic domestic furnace. Figure 2 is a schematic view of the furnace of Figure 1. Figure 3 is a schematic diagram illustrating a furnace controller of Figure 1 and the exemplary components in operative communication with the controller to execute a method for baking a dessert of according to one embodiment of the invention. Figure 4 is a schematic diagram illustrating a method for baking a dessert according to an embodiment of the invention. Figure 5 is a schematic graph illustrating a temperature and relative humidity in a cooking cavity of the oven of Figure 1 during the execution of the dessert baking method shown in Figure 4. Figure 6 is a table of the exemplary parameters for the implementation of the method for baking a dessert shown in Figures 4 and 5. With reference now to the figures, Figure 1 illustrates an exemplary automatic domestic oven 10 which can be used to implement a method for baking desserts with steam according to with one embodiment of the invention. The oven 10 comprises a cabinet 12 with an open-faced cooking cavity 14 defined by the walls of the cooking cavity: a pair of separate side walls 16, 18 attached to an upper wall 20, a bottom wall 22, a wall 23 later (Figure 2). A pivotable door 24 in a hinge 27 selectively closes the cavity 14 and a sensor 26 detects an open position of the door 24 and a closed position of the door 24. When the door 24 is in the open position, a user can have access to the door 24. the cavity 14 while the door 24 is in the closed position prevents access to the cavity 14 and seals the cavity 14 of the external environment. Furnace 10 further comprises a control panel 28 accessible to the user to enter desired data of the cooking parameters, such as the temperature and time of manual cooking programs or to select automated cooking programs. The control panel 28 communicates with a controller 30 located in the cabinet 12, as shown in Figure 2. The controller 30 can be a controller proportional to its integral and its derivative (PID) or any other suitable controller, such as it is well known in the automatic oven technique. The controller 30 stores data such as default parameters, manual input baking parameters and automated cooking programs, receives data input from the control panel 28, and sends the data output to the control panel 28 to display a condition of the oven 10 or otherwise communicate with the baker. Additionally, the controller 30 includes a timer 32 to maintain a time record during manual and automated cooking programs and a cooling fan 24 located in the cabinet 12 to draw cooling air into the cabinet 12 and direct the air in the direction of controller 30 to prevent overheating of controller 30 by heat conducted from cavity 14. Cooling air flows around the outside of cooking cavity walls 16, 18, 20, 22, 23. With continued reference to Figure 2, the oven
further comprises a heating system 35 having an upper heating element 36, commonly referred to as a grate, and a lower heating element 38. The schematic illustration of Figure 2 shows the lower heating element 38 being concealed or mounted below the cooking cavity bottom wall 22 in a housing 40 of the heating element. The heat from the lower heating element 38 is led through the bottom wall 22 and into the cavity 14. Alternatively, the lower heating element 38 can be mounted inside the cavity 14, as is well known in the oven art. In addition, the upper and lower heating elements 36, 38 can be mounted on the side walls 16, 18 of the cavity 14, as described in US Patent No. 6,545,251 to Allera et al., Which is incorporated herein by reference. reference in its entirety. The heating system 35 according to the illustrated embodiment further comprises a convection fan 42 which circulates air and steam, when present within the cavity 14. The convection fan 42 can be any suitable fan and can be mounted at any location of the cavity 14, such as in the rear wall 23. In addition to the heating system, the oven 10 comprises a steam system 44 preferably mounted within the cabinet 12 and configured to introduce steam into the cavity 14. The steam system 44 in the illustrated embodiment comprises a steam boiler 46 which heats the steam. water stored in steam system 44. However, the steam system 44 can be any suitable system that is capable of introducing steam directly into the cavity 14 or introducing water that becomes vapor in the cavity 14 and is not limited to the system shown schematically in Figure 2. Figure 3 is a block diagram schematically illustrating a control system of the furnace 10. The control system comprises the controller 30, which is operably communicated with the control panel 28 as described above, the sensor 26 of door, cooling fan 34, heating system 35, and steam system 44. The door sensor 26 communicates to the controller 30 the open or closed position of the door 24 and the controller 30 communicates with the cooling fan 34 to activate or deactivate the cooling fan 34 to control the temperature of the controller 30. The controller 30 instructs the heating system 35 to activate or deactivate the upper heating element 36, the lower heating element 38, and the convection fan 42, either all together, individually or in groups, and provides the instructions concerning the temperature of the cavity 14 and the speed at which the heating system 35 heats the cavity 14. Similarly, the controller 30 instructs the steam system 44 to activate or deactivate the steam boiler 46 and provide instructions concerning the desired temperature of the water in the steam system 44 to reach the desired relative humidity in the cavity 14. As established in The above, the exemplary oven 10 can be used to implement a method for baking a dessert with steam according to one embodiment of the invention. The method 50 comprises various steps during which the heating system 35 operates to control a temperature of the cavity 14 and the steam system 44 operates to control a relative humidity of the cavity 14. The temperature and relative humidity during the steps are they are selected to produce a dessert that has desired external and internal characteristics, such as texture and color. As used herein, the term "dessert" refers to any type of dessert that benefits from steam baking. Examples of desserts include, but are not limited to, delicate desserts such as créme brulee, cheesecakes, pies, custards, and soufflés. In addition, the method for baking a dessert according to the invention is also useful for cooking egg and cheese dishes such as quiche. The steps of the method 50 according to one embodiment of the invention are shown in a flow diagram of Figure 4, which shows the functions of the heating system 35 and the steam system 44 during each stage of the method 50, and the The corresponding temperature of the cavity 14 and the relative humidity of the cavity 14 for the stages are illustrated schematically in Figure 5. Figure 5 is not intended to report the actual behavior of the temperature and relative humidity during the method, rather, Figure 5 represents a general behavior of these properties. It will be apparent to someone with ordinary experience in the furnace technique that, in reality, the actual temperature and the actual relative humidity fluctuate
-5 around a target temperature and a relative humidity during the operation of a furnace. Before the first step of the method 50, the baker prepares the dessert and places the dessert and a corresponding dessert support, such as a baking dish or a baking tray, if used, inside the cavity 14, as shown in FIG. indicated by step 51 of Figure 4. In general, reference may be made to step 1 as a dry preheating step wherein the heating system 35 heats the cavity 14 to a first temperature at a first heating rate ri (step
52), and steam system 44 is off or not activated
(step 54). According to one embodiment of the invention, the first temperature is a temperature approximately equal to the boiling point of water. The first temperature is at least equal to about the boiling point of the water so that the vapor entering the cavity 14 during stage 2 maintains a vapor phase (or the water entering the cavity 14 will undergo a change phase). steam, if the steam system 44 introduces water into the cavity 14), as will be discussed in more detail below with respect to step 2. The first heating rate is relatively high so that the cavity 14 whereby the cavity 14 quickly reaches the first temperature. The heating immediately comprises heating the cavity 14 rapidly, such as by heating the cavity 14 as soon as possible or at a speed that minimizes the time for the cavity 14 to reach the first temperature. Stage 1 ends when cavity 14 reaches the first temperature or after the predetermined time period. Step 2 proceeds to step 1 and can generally be referred to as a pre-humidification stage where the steam system 44 is activated to heat the water, such as by the steam boiler 46, to pre-humidify the cavity 14 (step 56) while the heating system 35 continues to preheat the cavity 14. Wait until the end of stage 1 to start the steam system 44 ensures that the temperature of the cavity 14 is high enough to maintain the vapor in a vaporized state . As a result, the vapor will not condense in the cavity 14 and will form droplets of water in the walls 16, 18, 20, 22, 23, the dessert, or in any other element within the cavity 14. The formation of water droplets on the porcelain, which is a material that is found in the walls 16, 18, 20, 22, 23 of the cavity of many ovens, can undesirably damage the material. When the water in the steam system 44 reaches its boiling point, the steam begins to enter the cavity 14 and raises the relative humidity in the cavity 14. According to one embodiment of the invention, the relative humidity of the cavity 14 reaches maximum relative humidity during stage 2 or at least at the end of stage 2. Thus, at the end of stage 2, cavity 14 is moistened, a condition wherein the relative humidity of cavity 14 is greater than the relative humidity of the cavity 14 before the introduction of steam and is at a desired level for the initial baking of the dessert. At the same time, the heating system 35 raises the temperature of the cavity 14 to a second temperature at a second heating rate r2 lower than the first heating rate (step 58). According to one embodiment of the invention, the second temperature is just below a desired minimum steam bake temperature, as will be discussed in more detail thereafter. The second heating rate is relatively low so that the temperature of the cavity 14 slowly approaches the second temperature to avoid exposure of the dessert to excessive direct radiation and to ensure that the cavity 14 is uniformly heated. The term "uniformly heated" refers to all spaces and walls 16, 18, 20, 22, 23 of the cavity 14 and elements, such as baking grates, baking tins and baking trays, in the cavity 14 reaching the first temperature. A uniformly heated cavity results in a dessert item with a higher quality with consistent final characteristics. When the cavity 14 is heated uniformly and the baker opens and closes the door 24, the temperature of the cavity 14 almost immediately returns to the temperature of the cavity 14 before the opening of the door 24. When step 2 ends, either when the cavity
14 reach a desired relative humidity, such as the maximum relative humidity, or the second temperature, or after a predetermined period of time, stage 3 begins. During step 3, the heating system 35 increases the temperature of the cavity 14 to a third temperature (step 60) at a third heating rate r3 optionally greater than the second heating rate and less than the first heating rate, and Steam system 44 maintains the maximum or desired relative humidity (step 62). According to one embodiment of the invention, the third temperature is equal to a set temperature, which can be a temperature entered by a user through a user interface in the control panel 28 or set by an automatic cooking program , and is at least equal to the minimum desired steam bake temperature.
1
The user interface may comprise, for example, a button, a touch-sensitive keyboard, a touch-sensitive screen or a voice command unit. When the temperature of the cavity 14 reaches the third temperature or after a predetermined period of time, stage 4 begins. During stage 4, the heating system 35 maintains the temperature of the cavity 14 at the third temperature (step 64) , and steam system 44 decreases and / or terminates steam production. Because the amount of steam generated by the steam system 44 decreases or ceases while the steam in the cavity 14 is lost through the vents, the relative humidity of the cavity 14 gradually decreases (step 66). In addition, during step 4, the convection fan 42 ceases its operation, as indicated in step 64. The convection fan 42 is active during the preceding steps to help distribute air and steam throughout the cavity 14, but at this stage, the convection fan 42 is no longer necessary. The operation of stopping the convection fan 42 prevents an excessively fast cooking speed and undesired premature formation of an outer layer or bark on the outer surface of the dessert. After a predetermined period of time, stage 4 ends and stage 5 begins. Operationally, stages 4 and 5 are substantially identical in that the heating system 35 maintains the cavity 14 at the third temperature (step 68) while that steam system 44 continues to decrease and / or complete steam production (step 70). Again, because the amount of steam generated by the steam system 44 decreases or ceases while the steam in the cavity 14 is lost through the vents, the relative humidity of the cavity 14 gradually decreases. The vapor requirements for the dessert are reduced during the course of the cooking cycle, and at the end of step 5, the cavity 14 is uniformly hot and relatively dry, a condition where the relative humidity of the cavity 14 is relatively lower than the wetting condition and is at or near the relative humidity of the cavity 14 prior to the introduction of the steam. The duration of stage 5 can be variable and depends on a cooking cycle time entered by the user. In this circumstance, the duration of stage 5 is equal to the cycle time entered by the user minus the combined duration of stages 1-4. If the cycle time entered by the user is less than the combined duration of steps 1-4, step 5 can be eliminated, and the duration of stage 4 can be adjusted according to the cycle time entered by the user. Alternatively, the duration of step 5 can be set by an automatic cooking cycle. An exemplary implementation of the method 50 with the furnace 10 described in the foregoing, together with the exemplary operational parameter values, are presented below, with the understanding that the method 50 can be used with any suitable domestic furnace 10 and that the implementation of the Method 50 with different ovens can differ according to the oven used. The exemplary operational parameter values are shown in a table in Figure 6. During step 1, the heating system 35 rapidly heats the cavity 14 to approximately 100 ° C.
(212 ° F), the boiling point of water at sea level. It is well known in the chemistry art that the boiling point of water changes with altitude and dissolved content, and the first temperature can be adjusted accordingly. The duration of stage 1 is approximately 4 minutes; thus, the first heating rate is about 19.4 ° C per minute (35 ° F per minute) if the cavity 14 reaches 100 ° C (212 ° F) at the end of the 4 minutes. However, the cavity 14 can reach the first temperature before the end of the 4 minutes, if desired. The controller 30 instructs the heating system 35 to operate the upper heating element 36 at a duty cycle of 65% and the lower heating element 38 at a 100% duty cycle and to activate the convection fan 42. An exemplary duty cycle is the percentage of the time that the heating element is turned on (i.e. power is supplied to the heating element) during a certain time interval, such as 1 minute. The working cycle of the upper heating element 36 is lower than that of the lower heating element 38 to prevent overheating and excessively browning the exposed upper surface of the dessert that is already present in the cavity 14. After 4 minutes, the second stage, and the controller 30 instructs the heating system 35 to reduce the duty cycles of the upper and lower heating elements 36, 38 to 35% and 65% duty cycles, respectively, to slowly increase the temperature to approximately 120 ° C (248 ° F). The duration of step 2 is about 6 minutes, that is, the first heating rate is about 3.3 ° C per minute (6 ° F per minute) if the temperature of cavity 14 reaches about 120 ° C (248). ° F) at the end of 6 minutes. As with step 1, the temperature in cavity 14 can reach the second temperature prior to the end of 6 minutes if desired. Additionally, the steam system 44 communicates with the controller 30 and turns on the steam boiler 46 for 100% duty cycle operation to raise the relative humidity in the cavity 14 to the maximum relative humidity. As with the heating elements 36, 38, an exemplary duty cycle for the steam boiler 46 is the percentage of the time that the steam boiler 46 is turned on (i.e. power is supplied to the steam boiler 46) during certain time interval, such as 1 minute. During step 3, the work cycles of the upper and lower heating elements 36, 38 remain the same during the increase in the temperature of the cavity 14 to the third temperature, which, according to one embodiment of the invention, is a fixed temperature. The fixed temperature is a temperature at which the dessert is baked following preheating and usually fluctuates between about 121.11 ° C (250 ° F), the minimum desired baking temperature according to one embodiment of the invention, and 232.22 ° C (450 ° F). The second temperature of stage 2 can be suitably adjusted if the minimum desired baking temperature desired differs from 121.11 ° C (250 ° F). The duration of stage 3 is about 6 minutes, and cavity 14 can reach the fixed temperature before the end of 6 minutes and at least at the end of 6 minutes. In addition, the duty cycle of the steam boiler 46 is reduced so that the steam system 44 continues to form enough steam to replace the loss of steam through the vents or other medium and to maintain the maximum relative humidity during the 6 minutes . The cross section can be reduced to approximately 80%. After the 6 minutes of stage 3, stage 4, which lasts approximately 15 minutes, begins. During stage 4, the work cycles of the elements 3638, upper and lower heating remain the same to maintain the temperature of the cavity 14 at the fixed temperature, while the controller 30 turns off the convection fan 42, as described above, to avoid an excessively fast cooking speed and the formation of a top layer or bark. In addition, the controller 30 deactivates the steam boiler 46 of the steam system 44 so that the steam boiler 46 discontinues water heating. As a result, the temperature of the water decreases, the amount of steam decreases and the relative humidity of the cavity 14 gradually decreases to or near the relative humidity of the cavity 14 prior to the introduction of the steam in stage 2. After the stage 4, the controller starts stage 5, which has a variable duration that depends on the time of the cooking cycle entered by the user, as described in the foregoing. Operationally, the only difference between step 4 and step 5 is that the duty cycle of the lower heating element 38 is reduced to about 60%. The temperature of the water in the steam system 44 continues to decrease, and as a result, the amount of steam continues to decrease, and the relative humidity of the cavity 14 continues to gradually return to or near the relative humidity of the cavity 14 prior to the introduction of the steam in step 2. As mentioned in the above, the operational parameter values shown in Figure 6 depend on the furnace 10 used to implement the method. Different ovens have different types of heating systems
(for example, some ovens do not have the convection fan 42) and steam systems, which affects the implementation of the method 50. For example, the values of the above operational parameters were determined with the cooling fan 34 during the entire cycle of cooking. Because the cooling fan can draw heat from the cooking cavity 14 through the walls 16, 18, 20, 22, 23 of the cooking cavity, the cooling fan can affect the temperature of the cavity 14. When the baker wishes to bake a dessert using the method 50, the baker prepares the dessert, opens the door 24, places the dessert together with the dessert support, if used, in the cavity 14, and closes the door 24. Next, the user selects a "DESSERT" cooking cycle in the oven 10 through the control panel 28. The baker also enters the set temperature and the cooking cycle time, if necessary, through the control panel 28. The oven 10 then implements the method 50, starting in stage 1 and ending in stage 4 or stage 5. After step 5, the baker removes the dessert, which has the desired external and internal characteristics, such as texture and color of the cavity 14. In this way, the dessert is baked in a vaporized controlled environment and the baker does not have to attend the dessert during the baking process nor perform any dangerous home remedies to introduce steam into the cavity 14. Although the invention has been specifically described in conjunction with certain specific embodiments thereof, it should be understood that it is by way of illustration and not limitation, and the scope of the appended claims should be interpreted as broadly as the prior art permits.