Temperature control of an oven and method of operation

Abstract

A pizza oven 100 comprising a controller 145, a cooking chamber 105 with a cooking support 115 to support a pizza whilst cooking, a first heating component 125 configured to heat the upper surface of the support by radiation, and a second heating component 130 configured to heat the cooking support, and a pizza presence detector 140, wherein the controller is configured to operate at least one of the first and second heating elements, in accordance with, at different times, a default mode and a cooking mode, the operation of which depends on detection of the presence of a pizza (120, Fig.1d) by the presence detector. The cooking support may be a pizza stone 115, and at least one of the heat sources may be an electrically powered radiative heating element. A method of operating the pizza oven is also disclosed.

Description

Field of the invention The present invention relates to ovens and methods of temperature control thereof. Background to the invention It is known to heat an oven using heating elements positioned in an upper region of the cooking chamber, e.g. on the ceiling, and in a lower region of the cooking chamber, e.g. on the floor of the cooking chamber. In these ovens, the cooking chamber includes a cooking support on which food to be cooked in the oven is placed. The cooking support is heated by both heating elements in the upper and lower regions of the cooking chamber. Pizza ovens for cooking pizzas use a pizza stone to cook pizza. The temperature of the air inside the oven and the temperature of the pizza stone should be carefully regulated to ensure that the pizza is cooked well. However, it can be difficult to regulate temperatures of the air inside the pizza oven and the pizza stone effectively so that the pizza is cooked thoroughly but is also not overcooked. It is in this context that the present inventions have been devised. Summary of the invention In accordance with an aspect of the invention, there is provided a pizza oven. It may be that the pizza oven comprises a controller. It may be that the pizza oven comprises a cooking chamber comprising a cooking support configured to support a pizza whilst cooking. It may be that the pizza oven comprises a first heating component configured to heat the upper surface of the cooking support. It may be that the pizza oven comprises a second heating component configured to heat the cooking support. It may be that the pizza oven comprises a pizza presence detector configured to detect whether there is a pizza on the cooking support. It may be that the controller is configured to operate at least one of (typically each of) the first and second heating components in accordance with, at different times: a default mode and a cooking mode. It may be that the operation of the cooking mode depends on the detection of a pizza on the cooking support by the pizza presence detector. In accordance with an aspect of the invention, there is provided a method of operating a pizza oven. It may be that the pizza oven comprises a cooking chamber comprising a cooking support configured to support a pizza whilst cooking, a first heating component and a second heating component. It may be that the method comprises detecting whether there is a pizza on the cooking support. It may be that the method comprises operating at least one of (typically each of) the first and second heating components in accordance with, at different times: a default mode and a cooking mode. It may be that the operation of the cooking mode depends on the detection of a pizza on the cooking support. Advantageously, it is desirable to control the heating components in different operating modes depending on whether there is a pizza on the cooking support. The requirements for distribution of power between the first and second heating components depend on whether there is pizza on the cooking support. The first heating component heats the upper surface of the cooking support as it directly applies heat onto the upper surface of the cooking support, for example by way of heat (I R) radiation incident on (and absorbed by) the upper surface. When a pizza is present on the cooking surface, the first heating component directly heats the top of the pizza with heat (IR) radiation to cook the top of the pizza. The second heating component typically heats the cooking support directly, for example through radiation of heat onto the lower surface of the cooking support or internally within the cooking support. When a pizza is present on the cooking surface, the base of the pizza is cooked by conduction of heat from the cooking surface to the base of the pizza. Thus, the pizza is cooked at the base by conduction from the cooking support (which itself is heated by heat (IR) radiation from the second heating component) and the pizza is cooked on top by heat (IR) radiation from the first heating component. In this way, the heat to the base of the pizza and to the top of the pizza are independently regulated by independently regulating the first and second heating components. In order to be ready to receive and cook a pizza, the pizza oven has a default mode. The default mode may be a default pizza cooking mode. The oven may have other default modes too (for cooking other products). In the default mode, the pizza oven regulates the temperature of the cooking support and the hot air within the cooking chamber to be ready to cook a pizza. Pizza should be cooked quickly and at a high temperature (e.g. of between 300 °C to 500 °C). In particular a high stone temperature is important, and the upper surface of the pizza should also be heated. In the default mode, the first and second heating components are typically regulated to maintain the temperature of the cooking support at a target cooking support temperature. In order to cook a pizza, the pizza oven has a cooking mode. The cooking mode is a mode for cooking pizza. The oven may have other cooking modes too, for example, for cooking different products. In the cooking mode, the pizza oven regulates the temperature of the cooking support and the hot air within the cooking chamber to cook a pizza. Pizza should be cooked quickly and at a high temperature. In the cooking mode, the high stone temperature of the cooking support to cook the pizza base is typically achieved by heating the cooking support with the second heating component. In the cooking mode, the cooking of the upper surface of the pizza is typically achieved by heating the surface of the pizza with IR radiation incident on the top surface of the pizza. In the cooking mode, the first heating component is typically regulated to cook the top of the pizza. Because the first and second heating components are independently controllable and affect the heating of the top of the pizza, and the heating of the cooking support, differently, the cooking support temperature and the temperature of the heat applied to the top of the pizza can be controlled in the cooking mode to cook both sides of a pizza. It is advantageous to apply more heat using the first heating component once a pizza is on the cooking support and the oven is operating in the cooking mode than in the default mode because if the first heating component is used too much when there is no pizza on the cooking support, the incident IR radiation will heat the cooking support (typically even if the second heating component is off) in addition the IR radiation from the second heating component and the temperature of the cooking support can become too hot and burn a pizza when it is first placed on the cooking support. It may not be necessary to heat the cooking support in the cooking mode because the heat transferred from the cooking support to the base of the pizza when the cooking support already has been heated to the target cooking support temperature (i.e. during the default mode) is sufficient to cook the pizza. When a pizza is removed from the cooking support after it has cooked, the temperature of the cooking support is typically lower than the target cooking support temperature (i.e. the temperature of the cooking support when the pizza was placed on the cooking support). As a result, in order to cook more pizzas, the first and second heating components are operated in accordance with the default mode to increase and then maintain the temperature of the cooking support to the target cooking support temperature. Nevertheless, in some embodiments, it may be that the second heating component does not heat the cooking support during an initial phase of the cooking program but does heat the cooking support during a later phase (after the initial phase), for example, once the temperature of the air inside the cooking chamber has reached the target air temperature. By reference to the term “pizza oven”, we refer to an oven that is configured for cooking one or more pizzas. It may be that the cooking chamber of the pizza oven is configured for cooking one or more pizzas. It may be that the cooking chamber is configured for cooking one or more pizzas at an air temperature of at least 300 °C, at least 350 °C at least 400 °C or at least 450 °C. It may be that the cooking chamber is configured for cooking one or more pizzas at a cooking support temperature of at least 300 °C, at least 350 °C or at least 400 °C. It may be that the cooking chamber is dimensioned and sized for cooking one or more pizzas (e.g. the cooking support may have a largest dimension of at least 12 inches, e.g. at least 16 inches, e.g. at least 24 inches, optionally at least 30 inches, typically less than 50 inches). A cooking chamber configured for cooking one or more pizzas typically has a (e.g. interior) length and / or a (e.g. interior) breadth greater than a (e.g. interior) vertical height of the cooking chamber. The length of the cooking chamber refers to the horizontal distance extending from the left to the right side of the cooking chamber. The breadth of the cooking chamber refers to the horizontal distance extending from the front to the rear side of the cooking chamber. The height of the cooking chamber refers to the vertical distance extending from the top to the bottom of the cooking chamber. A pizza oven typically has a cooking chamber which is operable at air temperatures in excess of 375°C, which would not normally be the case for domestic kitchen ovens. The first and second heating components may be electric heat sources. It may be that at least one of the first and second heating components is a wire or ceramic heating element. It may be that at least one of the first and second heating components is an infra-red (IR) heating element. The first heating component may be configured to heat the interior of the cooking chamber. The first heating component may be configured to heat air inside the cooking chamber via radiation or convection. It may be that the first heating component is configured to heat the cooking surface by radiation. The second heating component may be provided in a lower region of the cooking chamber. The second heating component may be positioned underneath the cooking support. The second heating component may be positioned on the side of the cooking support opposite to the side of the cooking support on which the pizza is placed during cooking. The second heating component may be mounted onto the base of the oven. The second heating component may be mounted between the base of the oven and the cooking support such that it is not in direct contact with either the base of the cooking chamber or the cooking support. The second heating component may be integral with the cooking support. Part of the cooking support may be part of the second heating component. The second heating component may be mounted between the base of the oven and the cooking support such that it is in direct contact with at least one of: the base of the cooking chamber, and the cooking support. The second heating component may be less than 10 mm, less than 15 mm, or less than 20 mm from the cooking support. The first heating component may be positioned above the cooking support. The first heating component may be mounted onto the top internal surface of the cooking chamber. The first heating component may not be in direct contact with the top surface of the cooking chamber. The first heating component may be greater than 70 mm, greater than 80 mm or greater than 90 mm from the cooking support. Thus, the second heating component heats the cooking support and the first heating component heats the cooking support, or the pizza on the cooking support from above (and may heat the air above the cooking support). In use, the cooking support may be heated from underneath and above. Typically, there will be ongoing heat transfer between the cooking support and the air in the oven. The temperature of the cooking support is carefully regulated to ensure optimum cooking conditions. It may be that the first and second heating components are operable in either an off state or an on state. In the off state, typically no power is provided to the heating component. In the on state, typically a fixed power is provided to the heating component. That is, typically, the heating components are fully powered, or not powered at all, with the ratio of the time in which the heating component is in the on state, to the time in which the heating component is in the off state (e.g. the duty cycle) determining the average power output of the hearing component. It may be that, at any one time, only of the heating components is powered (i.e. in the on state). The first and second heating components may be configured to heat the cooking chamber to a temperature of at least 400 °C. The oven may be suitable for use at temperatures above 350 °C. The first and second heating components may heat air within the cooking chamber, and the cooking support, through temperatures from room temperature (e.g. 29 °C) up to a temperature at least 350 °C, or at least 400 °C, or at least 450 °C, or at least 500 °C. Where cooking chambers have temperatures above 350 °C, it is particularly helpful to have a controlled way to heat up the interior of the cooking chambers. It may be that first heating component is an electrically-powered radiative heating element. Typically, thermal radiation from the electrically-powered radiative heating element of the first heating component impinges on the upper surface of the cooking support. It may be that second heating component is an electrically-powered radiative heating element. Advantageously, radiative heating elements are particularly effective at heating the cooking chamber and cooking support to the high temperatures required for cooking pizza. This is particularly important for the first heating component which heats the cooking support from above (i.e. at a distance). In addition, radiative heating components, such as heating elements are readily available and convenient to use in domestic cooking appliances. It may be that the cooking support comprises a pizza stone. The pizza stone may comprise one or more pizza stone pieces, optionally two or more pizza stone pieces (e.g. exactly two pizza stone pieces). Advantageously, a pizza stone is particularly effective for cooking pizza because it has a high resistivity to thermal shock so that it is able to withstand high temperatures of up to 850°C without damage (e.g. cracking). In addition, a pizza stone radiates and conducts heat evenly. Therefore, cooking pizza on a pizza stone provides a pizza with an evenly cooked base. It may be that the cooking support is integral with the oven. It may be that the cooking support is removable from the oven without destroying either the oven or the cooking support. The cooking support may typically define a cooking surface. The cooking surface may be an upper surface of the cooking support. The cooking support may typically be a body of material having the cooking surface. The upper surface of the cooking support may define the base of the cooking chamber. The upper surface of the cooking support may face vertically upwards when the oven is in normal use. Infrared radiation from the first heating component may irradiate the cooking surface, and thereby heat the cooking support, when the first heating component is on. When a pizza is present it will typically cover part of the cooking surface and thereby reduce irradiation of the cooking surface by the first heating component, and thereby reduce the heating of the cooking support by the first heating component. The pizza stone may be a cordierite stone. It may be that the cooking support is a metal cooking support. Advantageously, the metal cooking support is able to withstand very high temperatures (in excess of 850 °C) without damage. It may be that the cooking support is a pizza steel. It may be that the cooking support is a cast iron pan or other metallic dish. The controller may comprise one or more processors. The controller may comprise a non-transitory computer readable memory storing instructions. The instructions, when executed by the one or more processors, may cause the controller to operate the first and second heating components. The one or more processors may be located in a single unit. In other examples, where the one or more processors is a plurality of processors, the controller may be distributed, which is to say that at least one of the plurality of processors may be located separated from at least one other of the plurality of processors. The cooking mode and the default mode may be collectively referred to as operating modes. The controller may be configured to regulate the temperature of the air inside the cooking chamber thermostatically, to thereby cause the temperature to be maintained at a setpoint. The setpoint of the air inside the cooking chamber may be at least 450 °C, or at least 500 °C, or at least 600 °C, for example at least 700 °C, such as at least 800 °C, for example at least 900 °C. The setpoint may be different in the cooking mode and the default mode. The controller may be configured to regulate the temperature of the cooking support thermostatically, to thereby cause the temperature to be maintained at a setpoint. The setpoint of the cooking support may be at least 400 °C, or at least 450 °C, or at least 500 °C. The setpoint may be the same in both operating modes. In an example, the setpoint may be 400 °C ± 5 °C. The setpoints may be selected by the user. The setpoints may be preprogrammed. The default mode may be operated in when there is no pizza on the cooking surface. The default mode may be operated in when there is no food item on the cooking surface. The default mode may be operated in when there is a food item other than a pizza on the cooking surface. It may be that, in the default mode, both the first and second heating components are configured into the on state. It may be that, in the default mode, both the first and second heating components are configured into the on state at the same time. It may be that, in the default mode, both the first and second heating components are alternately configured into the on state. The cooking mode may be operated in when there is a pizza on the cooking surface. It may be that, in the cooking mode, of the first and second heating components, only the first heating components is configured into the on state. It may be that the default mode corresponds to a manual mode. In the manual mode, the user may directly control the temperature of the cooking support using a user input, such as rotation of a temperature dial. The controller may be configured to receive at least one input from the one or more components of the oven, for example a temperature sensor. The controller may be configured to regulate at least one of: the first heating component and the second heating component. Typically, the oven comprises the controller, but in other examples, the controller may be provided separate from the oven and in wireless data communication therewith. Typically, the controller operates the first and second heating components by regulating the respective heating component. It may be that the controller regulates the heating components by transmitting controls signal to turn the heating component into the on state or the off state. The pizza presence detector may be a distributed system. The pizza presence detector may be distributed between the controller which operates the first and second heating components (e.g. a processor of the controller) and one or more components of the oven (e.g. a sensor and / or a user input device). The pizza presence detector may be distributed between a dedicated controller of the pizza presence detector and one or more components of the oven (e.g. a sensor and / or a user input device). Optionally, the pizza presence detector detects whether there is a pizza on the cooking support by determining a parameter associated with the oven. Optionally, the pizza presence detector detects whether there is a pizza on the cooking support by determining a measured parameter associated with the oven and comparing the measured parameter to a predetermined parameter associated with the oven. The detection of a pizza on the cooking support may be used as a trigger to initiate operation of the first and / or second heating component in the cooking mode. In this example, the method step of detecting whether there is a pizza on the cooking support may be performed before the method step of operating at least one of the first and second heating components in accordance with, at different times the cooking mode. Thus, in these embodiments, the cooking mode operates in dependence on the detection of a pizza on the cooking support because, in order for the cooking mode to commence, it depends on the detection of a pizza. The detection of a pizza on the cooking support may be used as a check of whether to continue operation of the first and / or second heating component in the cooking mode. In this example, the method step of detecting whether there is a pizza on the cooking support may be performed after the method step of operating at least one of the first and second heating components in accordance with, at different times the cooking mode. Thus, in these embodiments, it is possible that initiation of the cooking mode is user actuated and the cooking mode depends on the detection of a pizza on the cooking support because the cooking mode will stop if pizza is not detected. In other embodiments, the detection of a pizza on the cooking support could be made twice, once to trigger and initiate operation of the cooking mode and once as a check of whether to continue operation of the first and / or second heating component in the cooking mode. It may be that in the cooking mode, the average power output of the first heating component is changed, relative to the default mode. The average power output of the first heating component may be increased in the cooking mode. The average power output of the first heating component is typically selected to be appropriate for cooking the pizza, for example, for cooking the top surface of a pizza. It may be that an average power provided to the first heating component in the cooking mode is greater than an average power provided to the first heating component in the default mode. It may be that the method of operating a pizza oven comprises providing a greater average power to the first heating component in the cooking mode than an average power provided to the first heating component in the default mode. Advantageously, this has the effect of increasing power to the first heating component in the cooking mode compared to the default mode to thereby increase the temperature of the heat applied to the top of the pizza. This ensures that the pizza cooks thoroughly when there is a pizza on the cooking support. In the default mode, when there is not a pizza on the cooking support, it may be not necessary to apply as much heat to the cooking surface as applied to the top of the pizza in the cooking mode. Consequently, the average power provided to the first heating component in the default mode does not need to be as high as the average power provided to the first heating component in the cooking mode. Typically, it may be that the average power provided to the first heating component in the default mode is the average power provided to the first heating component to maintain a temperature of the air inside the cooking chamber at a default air temperature. Typically, the default air temperature is a temperature at which the air inside the cooking chamber is kept at when the oven has completed a heat up process (for example, an initial heat up process carried out on start-up, before cooking, or a subsequent heat up process carried out to prepare for cooking a pizza) and is not being used to cook a pizza. Typically, the average power provided to the first heating component is an average power over a 60 second time period. Typically, the average power provided to the first heating component is an average power over a 90 second time period. It may be that an average power provided to the second heating component in the default mode is greater than an average power provided to the second heating component in the cooking mode. It may be that the method of operating a pizza oven comprises providing a greater average power to the second heating component in the default mode than an average power provided to the second heating component in the cooking mode. Advantageously, this has the effect of increasing power to second heating component which heats the cooking support in the default mode, to compensate for heat from the cooking support being conducted into the pizza resting on the cooking support and / or the effect of the upper surface of the cooking support being shielded from the first heating component by the presence of the pizza in the cooking mode, across at least some of its area. Typically, the average power provided to the second heating component is an average power over a 60 second time period. Typically, the average power provided to the second heating component is an average power over a 90 second time period. It may be that the cooking mode starts with an initial phase in which the power to the second heating component decreases compared to the default mode (for example to zero) and the power to the first heating component increases compared to the default mode. The oven may be set to heat the cooking support to a target temperature. When the target temperature is reached, the user may place a pizza on the cooking support. At this point, the controller is configured to operate the first and second heating components in accordance with the cooking mode. As a result, the temperature of the cooking support will decrease rapidly as heat is transferred from the cooking support to the pizza (e.g. through conduction). When the pizza is removed from the cooking support, the second heating component is used to reheat the cooking support to replace the heat that was lost from the cooking support through conduction from the cooking support into the pizza. This is referred to herein as recharging the cooking support. In the default mode, the second heating element may be kept in an on state until the cooking support reaches a target temperature. It may be that, in the default mode, the controller is configured to control the second heating component to maintain a temperature of the cooking support to within a threshold of a target temperature of the cooking support. It may be that the method of operating a pizza oven comprises, in the default mode, controlling the second heating component to maintain a temperature of the cooking support to within a threshold of a target temperature of the cooking support. Advantageously, for a pizza oven, it is particularly desirable to heat the cooking support to the target temperature to ensure that the base of the pizza will cook thoroughly in a short time period. This contrasts with existing ovens which regulate the air temperature to bring the air temperature to the target temperature. Typically, the target temperature is at least 400 °C, or at least 450 °C, or at least 500 °C. The threshold may be within 20 °C, for example within 10 °C, such as within 5 °C, for example within 1 °C, such as within 0.5 °C. The threshold may be within 0 °C of the target temperature. That is, the cooking support may be maintained to a temperature equal to the target temperature. The first heating component typically may also indirectly heat the air inside the cooking chamber between the first heating component and the upper surface of the cooking support when the heat is radiated through the cooking chamber and onto the upper surface of the cooking support (or pizza). The first heating component may therefore heat the air inside the cooking chamber to a greater extent than the lower heating component. Thus, the temperature of the air inside the cooking chamber and the temperature of the cooking support may also be independently regulated by independently regulating the first and second heating components. In the cooking mode, the first heating component may be regulated to increase the temperature of the air in the cooking chamber to a target air temperature. Typically, in the default mode, at least the first, and typically also the second heating components, may be regulated to maintain the temperature of the air in the cooking chamber at a default air temperature. Typically, the default air temperature may be greater than the target cooking support temperature, typically by at least 50°C. Because the first and second heating components may be independently controllable and affect the heating of the air in the cooking chamber, and the heating of the cooking support, differently, the cooking support temperature and air temperature may be controlled in the default mode to be ready to cook a pizza. It may be advantageous to enable the temperature differential between the air and the cooking support because if the cooking support temperature is allowed to get too close to the target air temperature, the cooking support may be too hot and could burn a pizza when it is first placed on the cooking support. The temperature of the air in the cooking chamber may be maintained at the target air temperature throughout the operation of the oven in the cooking mode. Typically the target air temperature may be greater than the default air temperature, typically by at least 50 °C, or at least 100 °C. Typically, the target air temperature may bes greater than the target cooking support temperature, typically by at least 100 °C or at least 150°C. Typically, the second heating component may not be powered during at least an initial phase (typically of at least 10 seconds) of the cooking mode. Typically the first heating component may be powered during this initial phase. Thus, during the initial phase, increasing the air temperature using the first heating component may be prioritised. During the initial phase, heat transfer into a pizza from the cooking support may be by conduction and depend on the pre-existing temperature of the cooking support at the beginning of the initial phase. Typically, the default air temperature in the default mode may be sufficiently high that the time required to increase of the temperature of the air inside the cooking chamber to the target air temperature in the cooking mode is relatively short. When a pizza is removed from the cooking support after it has cooked, typically, the first and second heating components may be operated in accordance with the default mode to maintain the temperature of the air inside the cooking chamber at the default air temperature. It may be that, in the default mode, the controller is configured to control the first heating component to regulate a temperature of the air inside the cooking chamber to within a default air temperature range. It may be that, in the cooking mode, the controller is configured to control the first heating component to increase the temperature of the air inside the cooking chamber to at least 100°C above the default air temperature range. It may be that the method of operating a pizza oven comprises, in the default mode, controlling the first heating component to regulate a temperature of air inside the cooking chamber to within a default air temperature range. It may be that the method of operating a pizza oven comprises, in the cooking mode, controlling the first heating component to increase the temperature of the air inside the cooking chamber to at least 100°C above the default air temperature range. Advantageously, the temperature of the air inside the cooking chamber is lower in the default mode, when the high temperatures required to cook the top of the pizza are not necessary because there is no pizza in the oven. When a pizza is present on the cooking support, the temperature of the air inside the cooking chamber is increased when in the cooking mode to ensure the temperature of the air inside the oven is high enough to cook the top of the pizza. Typically, the default air temperature range may have a lower limit of at least 450 °C, or at least 500 °C, at least 550 °C or at least 600 °C. Typically, the default air temperature range may have an upper limit of at least 500 °C, or at least 550 °C, at least 600 °C or at least 650 °C. The increase to the temperature of the air inside the cooking chamber in the cooking mode may be at least 100 °C, for example at least 200 °C, such as at least 300 °C, for example at least 400 °C. above the lower limit of the default air temperature range. The increase to the temperature of the air inside the cooking chamber in the cooking mode may be at least 100 °C, for example at least 200 °C, such as at least 300 °C, for example at least 400 °C. above the upper limit of the default air temperature range. It may be that the time taken for the temperature of the air inside the cooking chamber to increase from the temperature in the default mode to the temperature in the cooking mode is at most 45 seconds, at most 30 seconds, such as at most 20 seconds, for example at most 15 seconds, such as at most 10 seconds, for example at most 5 seconds, such as at most 2 seconds. It may be that, in the default mode, the (e.g. the lower limit or the upper limit of) default air temperature range is at least 50°C greater than the target temperature of the cooking support. It may be that, in the default mode, controlling the first and second heating components such that the (e.g. the lower limit or the upper limit of) default air temperature range is at least 50°C greater than the target temperature of the cooking support. Advantageously, the temperature differential between the air inside the cooking chamber and the cooking support means that the temperature of the cooking support is maintained at a lower temperature than the air inside the cooking chamber so that the cooking support does not get too hot and so the pizza will not burn when it is first placed on the cooking support. It may be that, in the default mode, the (e.g. the lower limit or the upper limit of) default air temperature range is at least 75°C greater than the target temperature of the cooking support. It may be that, in the default mode, the (e.g. the lower limit or the upper limit of) default air temperature range is at least 100°C greater than the target temperature of the cooking support. It may be that, in the default mode, controlling the first and second heating components such that the (e.g. the lower limit or the upper limit of) default air temperature range is at least 75°C greater than the target temperature of the cooking support. It may be that, in the default mode, controlling the first and second heating components such that the (e.g. the lower limit or the upper limit of) default air temperature range is at least 200°C greater than the target temperature of the cooking support. It may be that, in the cooking mode, the controller is configured to control the first heating component to draw a maximum power. It may be that the method of operating a pizza oven comprises, in the cooking mode, controlling the first heating component to draw a maximum power. Advantageously, drawing the maximum power from a power supply to the oven allows the first heating component to quickly increase the temperature of the air inside the cooking chamber when operating in accordance with the cooking mode. The maximum power may be a predetermined maximum power. The maximum power may be a rated maximum power. It may be that the maximum power drawn from the power supply is at least 1000 W, for example at least 1200 W, such as at least 1400 W, for example at least 1600 W, such as at least 1800 W. It may be that the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) a detection of presence of a pizza on the cooking support. It may be that the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (ii) a user input. It may be that the method of operating a pizza oven comprises initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support. It may be that the method of operating a pizza oven comprises initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (ii) a user input. Advantageously, the detection of presence of a pizza on the cooking support and the user input are two options for triggers to initiate the cooking mode. In option (i), it may be that, responsive to the detection of presence of a pizza on the cooking support, the controller switches from the default mode to the cooking mode to cook the pizza that is detected on the cooking support automatically without user input being required. This is an automated system which can operate with minimal user input. In option (ii), when the user input is the trigger to initiate the cooking mode, the controller is able to switch from the default mode to the cooking mode to cook the pizza with the user providing the instructions to do so. This relies on user input to initiate the cooking mode, which can improve accuracy of operation of the cooking mode. It may be that that the pizza presence detector detects the presence of a pizza on the cooking support and, in response, the controller transmits control signals to operate the first and / or second heating component in accordance with the cooking mode. It may be that the control signals cause the average power output of the first and / or second heating components to change. It may be that average power output of the first and / or second heating components is varied by switching them between two power levels (typically on and off) with a variable duty cycle. It may be that the first and second heating components are operated in a predetermined ratio of average power. The user input may typically be received using a user input device. The pizza oven may comprise a user input device. The user input device may comprise one or more of: a rotatable dial, a button, a keypad, a touchscreen or microphone. The user may provide the user input by rotating the dial, pressing the button, pressing the keypad, touching the touchscreen or a vocal input to the microphone. Other types of user inputs will also be envisaged. The user input device may be part of a user interface of the oven. When the user provides the user input, a data and / or control signal may be transmitted to the controller. The controller may receive the data and / or control signal and use this information to operate at least one of the first and second heating components in accordance with either the default mode or the cooking mode. It may be that the user input is indicative of a type of pizza to be cooked. It may be that the type of pizza is a Neapolitan pizza. Advantageously, the oven can operate the heating components in a particular operating mode (e.g. the cooking mode) depending on the type of pizza on the cooking support. The type of pizza on the cooking support is accurate because it is inputted by the user who knows what type of pizza is being cooked. This is especially beneficial because the cooking mode is particularly effective at cooking Neapolitan pizza. For example, when operating in the cooking mode, more power is provided to the first heating component to heat the air inside the cooking chamber than the power provided to the second heating component. This means that the base and toppings of the Neapolitan pizza are cooked thoroughly whilst preventing them from burning. It may be that the pizza presence detector comprises one or more sensors configured to detect a pizza on the cooking support. It may be that the method comprises detecting a pizza on the cooking support. It may be that the method comprises using one or more sensors to detect a pizza on the cooking support. Advantageously, the pizza presence detector automatically detects the presence of a pizza on the cooking support to initiate the cooking mode without requiring further user input. That is, the insertion of the pizza into the cooking chamber and on the cooking support is sufficient action by the user to cause the controller to begin to operate at least one of the first and second heating components in the cooking mode. Typically, the sensor may comprise at least one of: a temperature sensor, a camera, a weight sensor, a photodetector, a LIDAR (time of flight) sensor, light gate sensor, an acoustic sensor and an electro-optical sensor. Other types of sensors will be envisaged. It may be that the pizza presence detector is configured to detect presence of a pizza on the cooking support using the measurement from the sensor. It may be that the method comprises detecting a pizza on the cooking support using the measurement from the sensor. For example, where the sensor is a camera, the pizza presence detector may use machine learning techniques to detect that there is a pizza on the cooking support. In another example, where the sensor is an electro-optical sensor, the pizza presence detector may detect, from the signal generated by the change in light detected by the sensor, that there is a pizza on the cooking support. It may be that the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support. It may be that the one or more sensors comprise a weight sensor configured to measure a weight of the cooking support and any food supported thereon. It may be that the pizza presence detector is configured to detect whether there is a pizza on the cooking support in dependence on the weight associated with the pizza oven. It may be that the method comprises initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support. It may be that the method comprises measuring a weight of the cooking support and any food supported thereon. It may be that the method comprises detecting whether there is a pizza on the cooking support in dependence on the weight associated with the pizza oven. Advantageously, the pizza presence detector uses a weight measurement of the oven to determine whether a pizza is present on the cooking support to trigger the operation of the cooking mode. The weight of the oven is a reliable indication of the presence of a pizza because the weight of the oven increases when a pizza is placed in the oven. It may be that the weight sensor is a load cell. It may be that the weight sensor is located in a base of the oven. It may be that the weight sensor is located in legs of the oven. It may be that the weight sensor is located beneath the cooking support. It may be that the pizza presence detector detects that there is a pizza on the cooking support when the weight associated with the pizza oven increases. It may be that the pizza presence detector detects that there is a pizza on the cooking support when the weight associated with the pizza oven increases by a predetermined weight range. Advantageously, the weight range can be predetermined to correspond to the weight of the average pizza so that the pizza presence detector will not detect the presence of a pizza based on just any increase in the weight of the cooking support and any food supported thereon. This means that the pizza presence detector will not detect the presence of a pizza when a lighter object than a pizza, such as an oven glove is placed on the oven, or when a heavier object than a pizza, such as a plant pot is placed on the oven. As an example, the predetermined weight range may be an increase having a range of 0.05 kg to 0.7 kg, such as 0.2 kg to 0.6 kg, for example 0.2 kg to 0.4kg. For example, for a 12” to 16” pizza, a rolled-out dough ball with toppings on top may weigh approximately 0.4 kg to 0.6 kg. Therefore, the predetermined weight range may be an increase having a range of 0.4 kg to 0.6 kg (fora 12” to 16" pizza). It will be appreciated that the cooking surface, the larger the pizza may be and therefore the heavier the pizza may be. As such, for larger pizzas, the predetermined weight range may be greater than 0.4 kg to 0.6 kg. It may be that the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support. It may be that the pizza oven comprises an openable door to provide access to the cooking support. It may be that the one or more sensors comprise a door sensor configured to determine whether the door is open or closed. It may be that the pizza presence detector is configured to detect the presence of a pizza on the cooking support by taking into account whether the door is open or closed, as determined by the door sensor. It may be that the method comprises initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support. It may be that the method comprises determining whether an openable door of the oven door is open or closed. It may be that the door provides access to the cooking support. It maybe be that the method comprise detecting the presence of a pizza on the cooking support by taking into account whether the door is open or closed, as determined by the door sensor. Advantageously, the provision of the door sensor improves the accuracy of the determination by the pizza presence detector of presence of a pizza on the cooking support, without requiring input from the user. This is because the movement of the door can indicate whether the door has been open and / or closed to insert and / or remove the pizza from the cooking support. In addition, the door can be closed to increase the speed at which the temperature inside the cooking chamber, and the temperature of the cooking support increases because hot air is not lost through the opening to the oven. It may be that the door sensor is a pressure sensor. In this example, the pressure sensor is located on the oven such that when the door is open, no pressure is exerted by the door on the pressure sensor and when the door is closed, the door exerts a pressure on the pressure sensor. It may be that the door sensor is a motion sensor. In this example, the motion sensor is located on the oven such that it is able to detect motion of the door when it is open or closed. It may be that the door sensor is a presence sensor (e.g. an optical sensor). In this example, the presence sensor is located on the oven such that when the door is open, the sensor does not detect the presence of the door and when the door is closed, the presence sensor does not detect the presence of the door. Typically, the door sensor may determine whether the door is open or closed depending on the detection from the door sensor. It may be that the controller is configured to receive a signal from the door sensor indicative of the door being open or closed. It may be that the cooking mode is initiated in dependence on an open to closed transition of the door. Typically, the openable door at least partially seals the cooking chamber by closing the front opening of the oven. Typically, the front opening of the oven may be open and closed by the openable oven door. The oven door is typically moveable between a closed position, in which the (i.e. interior of the) cooking chamber is (i.e. at least partially) sealed from an external atmosphere (i.e. outside the oven), and an open position, in which the (i.e. interior of the) cooking chamber is externally accessible (i.e. from outside the oven). The oven door may be hingedly attached to the oven such that moving the oven door between the open and closed positions comprises rotating the oven door about a hinge. The oven door may be configured to close the opening. The front opening is typically accessible by a user (for example, for the provision, inspection or removal of pizza within the cooking chamber) when the oven door is provided in the open position. The oven door may comprise a window. The window may be made of one or more transparent materials. The window may be made of glass. Typically, “taking into account” comprises considering the respective parameter in the determination made by the pizza presence detector. Typically, “taking into account” comprises making the determination in dependence on the value or result of the respective parameter. That is, when the door is opened, the controller may be configured to operate at least one of the first and second heating components in the cooking mode. In some examples, when the door is closed, the controller may be configured to operate at least one of the first and second heating components in the cooking mode. That is, movement of the door, whether to open or close it, is triggers the operation of the cooking mode. It may be that the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support. It may be that the one or more sensors comprise a temperature sensor. It may be that the pizza presence detector is configured to detect whether there is a pizza on the cooking support in dependence on the measured temperature. It may be that the method comprises initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support. It may be that the method comprises measuring a temperature of the cooking support. It may be that the method comprises detecting whether there is a pizza on the cooking support in dependence on the measured temperature. Advantageously, the temperature of the cooking support is a parameter which responds fairly quickly and dramatically in response to the placement of a pizza on the cooking support. In particular, the temperature of the cooking support changes rapidly when a pizza is placed on the cooking support. Therefore, measuring the temperature of the cooking support provides a reliable indication of whether there is a pizza on the cooking support. Optionally, the temperature measures the temperature of the cooking support by directly measuring the temperature of the cooking support. Typically, the pizza presence detector uses the temperature measured by the temperature sensor to determine whether a pizza is present on the cooking support. The confirmation of whether a pizza is present on the cooking support may be dependent on the measured temperature because the temperature of the cooking support changes when a pizza is placed on the cooking support. Typically, the temperature of the cooking support may be measured at regular intervals. The temperature measured at consecutive intervals may be used to determine whether the temperature of the cooking support is decreasing. It may be that the pizza presence detector compares the measured behaviour of the temperature of the cooking support (i.e. increasing or decreasing) to the expected behaviour of the cooking support. It may be that the pizza presence detector comprises a temperature sensor configured to measure a temperature of the cooking support. It may be that the pizza presence detector comprises a temperature sensor configured to measure a temperature of the cooking surface. It may be that the temperature sensor is a thermocouple, a negative temperature coefficient (NTC) thermistor, a semiconductor IC sensor or a resistance temperature detector (RTD). Optionally, the temperature sensor is in contact with the cooking support. Optionally the temperature sensor is within 0.5 cm, within 1 cm, within 1.5 cm, within 2 cm or within 2.5 cm of the cooking support. When the cooking support is a metal cooking support, other ways of determining the temperature of the cooking support may be used, such as other sensors. It may be that measuring the weight of the cooking support and any food supported thereon, measuring the temperature of the cooking support or determining whether the door of the oven is open or closed comprising using the one or more sensors. It may be that the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (ii) the user input. It may be that the pizza presence detector is configured to: confirm whether a pizza is present on the cooking support. It may be that the controller is configured to continue operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on confirmation that a pizza is present on the cooking support. It may be that the controller is configured to terminate operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on the absence of confirmation that a pizza is present on the cooking support. It may be that the method comprises initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) the user input. It may be that the method comprises confirming whether a pizza is present on the cooking support. It may be that the method comprises continuing operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on confirmation that a pizza is present on the cooking support. It may be that the method comprises terminating operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on the absence of confirmation that a pizza is present on the cooking support. It may be that the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support. It may be that the pizza presence detector is configured to: confirm whether a pizza is present on the cooking support. It may be that the controller is configured to continue operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on confirmation that a pizza is present on the cooking support. It may be that the controller is configured to terminate operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on the absence of confirmation that a pizza is present on the cooking support. It may be that the method comprises initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support. It may be that the method comprises confirming whether a pizza is present on the cooking support. It may be that the method comprises continuing operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on confirmation that a pizza is present on the cooking support. It may be that the method comprises terminating operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on the absence of confirmation that a pizza is present on the cooking support. Advantageously, the confirmation of whether a pizza is presenton the cooking support provides a sense check as to whether there is a pizza on the cooking support. This is particularly useful as it provides increased certainty in the detection of presence of a pizza on the cooking support. Therefore, this reduces the possibility of the controller operating at least one of the first and second heating components in accordance with the cooking mode erroneously. It may be that confirming whether a pizza is present on the cooking support comprises detection of a parameter which indicates that a pizza is on the cooking support. For example, a change in weight of the cooking support and any food supported thereon, a change in oven door position, a change in temperature of the cooking support or other detection using a sensor. It may be that the confirmation of whether a pizza is present on the cooking support is made after a predetermined time period following initiation of the cooking mode. Typically, the predetermined time period may be at least 5 seconds, such as at least 10 seconds, for example at least 15 seconds, such as at least 20 seconds. If it is confirmed that a pizza is present on the cooking support, the controller may continue to operate the first and second heating components in accordance with the cooking mode because there is a pizza on the cooking support. If there is a lack of confirmation that a pizza is present on the cooking support, the controller may terminate operation of the first and second heating components in accordance with the cooking mode because there is not a pizza on the cooking support. If there is a lack of confirmation that a pizza is present on the cooking support, the controller may switch operation of the first and second heating components in accordance with the cooking mode to the default mode. When the confirmation occurs in the instance where initiation of the cooking mode depends on detection of a pizza, the detection of a pizza may be made twice. The first time is initiate the cooking mode and the second time is to confirm whether to continue operating in the cooking mode. It may be that the first and second detections of a pizza on the cooking support are made using the same sensor or a different sensor. When the confirmation occurs in the instance when initiation of the cooking mode depends on a user input, the detection of a pizza may be made once (i.e. when confirming whether to continue operating in the cooking mode). It may be that at least one of the one or more sensors are used in the confirmation that a pizza is present on the cooking support. It may be that confirming whether a pizza is present on the cooking support comprises using the one or more sensors. It may be that the detection of a pizza on the cooking support to confirm whether to continue operating in the cooking mode is made using the one or more sensors of the pizza presence detector. That is the detection of a pizza on the cooking support to confirm whether to continue operating in the cooking mode may be made in the same way as the detection of a pizza on the cooking support to initiate operation of the cooking mode is made (e.g. as described above in relation to the weight, door or temperature sensors). It may be that the confirmation that a pizza is present on the cooking support is dependent on a measured temperature of the cooking support. It may be that confirmation that a pizza is present on the cooking support corresponds to the temperature of the cooking support decreasing. It may be that the pizza presence detector is configured to determine that the temperature of the cooking support has decreased by comparing a first temperature measurement, taken by the temperature sensor at a first time, to a second temperature measurement taken by the temperature sensor at a second time, after the first time. It may be that the method of operating a pizza oven comprises determining that the temperature of the cooking support has decreased by comparing a first temperature measurement, taken at a first time, to a second temperature measurement taken at a second time, after the first time. Advantageously, the temperature of the cooking support decreasing provides a reliable indication that there is a pizza on the cooking surface. This is because, when a pizza is on the cooking support, the temperature of the cooking support decreases rapidly as heat is transferred from the cooking support (particularly the cooking surface) to the pizza. The interval between the first and second times may be less than 30 seconds, for example less than 20 seconds, such as less than 15 seconds, for example less than 10 seconds, such as less than 5 seconds, for example less than 2 seconds. Typically, the temperature sensor may be configured to take a measurement of the first temperature measurement when the operation of the at least one of the first and second heating components in accordance with the cooking mode is initiated. Typically, the pizza presence detector may be configured to determine that the temperature of the cooking support has decreased between the first and second times. Typically, the pizza presence detector may confirm whether a pizza is present on the cooking support by taking into account the determination that the temperature has decreased. Typically, the method of operating a pizza oven comprises measuring the first temperature measurement when the operation of the at least one of the first and second heating components in accordance with the cooking mode is initiated. Typically, the method of operating a pizza oven comprises measuring the second temperature measurement when the operation of the at least one of the first and second heating components in accordance with the cooking mode at a period of time after the cooking mode is initiated. Typically, the method comprises comparing the first and second temperature measurements. Typically, the method comprises confirming that a pizza is present on the cooking support when the temperature of the cooking support has decreased. The oven is a pizza cooking apparatus used to heat and cook a pizza placed therein. The pizza inside the oven is cooked in the cooking chamber which is typically heated to a temperature that is set by the user, either directly or indirectly. The cooking chamber is typically defined by the oven. Typically, an oven is used to cook a variety of pizza types, having different sizes, shapes and cooking requirements. It may be that the oven comprises an oven housing defining the cooking chamber therein. It may be that the cooking chamber is a region inside the oven in which the pizza is placed for cooking. The oven housing may define a front opening which is an access point for the cooking chamber. The cooking chamber is typically internal to the oven, that is to say it is an internal cooking chamber. The cooking chamber and / or the housing may each comprise (e.g. be defined by) one or more walls. The housing and the cooking chamber may comprise a top, base, left side, right side and rear (e.g. in addition to the front opening). An internal space may be defined between the (e.g. walls of the) housing and the (e.g. walls of the) cooking chamber. The oven (and optionally the cooking chamber) may be understood to comprise a front portion (e.g. half) and a rear portion (e.g. half) with the front portion being closer to the front opening, and the rear portion being further from the front opening. The oven (and optionally the cooking chamber) may be understood to comprise an upper portion (e.g. half) and a lower portion (e.g. half) with the upper portion being closer to the top of cooking chamber, and the lower portion being closer to the base of the cooking chamber. The first heating component may be positioned in the upper portion of the oven. The second heating component may be positioned in the lower portion of the oven. It may be that the oven is (i.e. configured as) a portable oven. For example, the oven may be smaller and / or lighter than a conventional oven such that the oven may be moved easily by a user. It may be that the oven is provided with legs, feet, castors, rollers, wheels and / or an oven stand such that the oven may be safely positioned on the floor or on a surface, such as a table or countertop, inside during use. The oven may comprise legs extending from the base of the housing. It may be that a (i.e. external) housing of the oven is (i.e. thermally) insulated such that a user may safely handle one or more external portions of the oven during use. The front opening may be for the insertion and removal of pizza. The width of the front opening may be the extent of the front opening from one side to the other in a horizontal plane in use. The front opening may have a breadth greater than its vertical height, optionally to align with the dimensions of the cooking chamber. Typically, the breadth to vertical height ratio is in the range of 10:1 to 2:1, preferably in the range 5:2 to 5:1. This dimension ratio is similar to the dimension ratio of a pizza which typically has a radius (or width and length) greater than its vertical height. The term “front” is intended to refer to the part of the oven which would face the user during use when inserting and / or removing pizza from the pizza oven. The term “rear” is intended to refer to the opposite side of the oven from the “front” of the oven. By words such as upright, top, bottom, horizontal and vertical, we refer to directions when the oven is arranged for use with the base of the cooking chamber horizontal. Pizza is cooked horizontally and so the configuration of the oven region and its base defines the orientation of the pizza oven when it is arranged for use. The oven housing may further comprise one or more ground engaging legs which further define the orientation of the oven when it is arranged for use. The cooking chamber typically includes the cooking support, which is a support on which the pizza to be cooked in the oven is placed to support the pizza during cooking. The cooking support typically defines a cooking surface. The cooking surface may be a continuous, or the cooking surface may be perforated. The cooking support may be formed of any material which is capable of storing thermal energy, for example ceramic, cordierite stone or metal. The cooking support may be integrated with the cooking chamber or removable from the cooking chamber. The cooking surface typically may face the first heating component. The cooking support may have a high resistivity to thermal shock so that it is able to withstand high temperatures of up to 850 °C without damage (e.g. cracking). The cooking support may transmit heat evenly throughout the cooking support. Although the pizza oven may be primarily intended for cooking pizzas, it will be appreciated that other pizza can be cooked in the pizza oven. For example, the pizza oven may be used to cook meat or pasta. It maybe that different pizza types require different cooking temperatures, and that the pizza oven is configured to cause the cooking chamber to reach these temperatures, e.g. in use. If the pizza is capable of fitting through the front opening of the pizza oven, then it can likely be cooked in the pizza oven. It may be that the pizza is cooked inside the pizza oven using a cooking accessory, such as a pan or cast iron skillet. These accessories may be placed onto the pizza-receiving base (e.g. the pizza stones) during cooking. Description of the Drawings An example embodiment of the present invention will now be illustrated with reference to the following Figures in which: Figures 1a, 1b, 1c and 1d are schematics of a pizza oven according to an embodiment of the invention; Figure 2 is a flowchart of a method according to an embodiment of the invention; Figure 3 is a schematic of pizza ovens according to an embodiment of the invention; Figure 4 is a flowchart of a method according to an embodiment of the invention; Figure 5 is a schematic of pizza ovens according to an embodiment of the invention; Figure 6 is a flowchart of a method according to an embodiment of the invention; Figure 7 is a schematic of pizza ovens according to an embodiment of the invention; Figure 8 is a flowchart of a method according to an embodiment of the invention; Figure 9 is a schematic of a controller according to an embodiment of the invention; and Figures 10a and 10b are graphical representations of temperature changes of the cooking support and the air inside the cooking chamber, respectively, according to an embodiment of the invention. Detailed Description of an Example Embodiment Figures 1a, 1b, 1c and 1d illustrate a schematic of a pizza oven 100 according to an embodiment of the invention. In Figures 1a to 1c, the pizza oven 100 is operating in the default mode. In Figure 1 d, the pizza oven is operating in the cooking mode, with a pizza 120 present. The pizza oven 100 includes a cooking chamber 105 which is heated and provides the space for a pizza to be cooked in the oven. Inside the cooking chamber 105, there is a cooking surface 110, which is the upper surface of a pizza stone, which functions as the cooking support 115. Access to the cooking chamber 105 is provided by an oven door 155, which is attached to the oven 100 by a hinge. In Figure 1c, the door 155 is shown partially because it is open. On the ceiling of the cooking chamber 105, there is an upper heating element, which functions as the first heating component 125. The upper heating element 125 radiates heat down towards the upper surface 110 of the pizza stone 115. As shown by the curved arrows above the pizza stone 115 in Figure 1a, the heat from the upper heating element 125 is radiated into the cooking chamber and onto the pizza stone 115, in particular the cooking surface 110. Underneath the pizza stone 115, there is a lower heating element, which functions as the second heating component 130. The lower heating element 130 radiates heat upwards towards the lower surface of the pizza stone 115 as shown by the curved arrows underneath the pizza stone 115 in Figure 1a. The cooking surface 110 is primarily heated via heat transfer through the pizza stone 115 from the lower surface of the pizza stone 115 to the cooking surface 110 (i.e. the upper surface of the pizza stone 115). The pizza stone 115 is supported by stands 175a, 175b which hold the pizza stone 115 away from the lower heating element 130 so that the pizza stone 115 and the lower heating element 130 are not in direct contact with one another. However, in some examples, the lower heating element 130 is in direct contact with the pizza stone 115. The oven 100 includes a controller 145 which controls the upper 125 and lower 130 heating elements. The controller 145 has a default mode, to prepare the oven for cooking a pizza, and a cooking mode for use when cooking a pizza. In the default mode, the controller 145 controls the upper 125 and lower 130 heating elements to obtain a desired air temperature and cooking surface temperature. In the default mode, the controller 145 operates the upper 125 and lower 130 heating elements in the states shown in Figure 1a and Figure 1b, and also an off state. In the state shown in Figure 1a, the upper 125 and lower 130 heating elements are both in an on state. In the state of Figure 1b, the upper heating element 125 in an off state and the lower heating element 130 in the on state. The controller causes the upper and lower heating elements to alternate between the states of Figure 1a and Figure 1b with time periods selected to raise the temperature of the cooking surface 110 to a target temperature for cooking a pizza and to raise the temperature of the air inside the cooking chamber 105 to a temperature within the default air temperature range. In this example, the target temperature of the cooking surface 110 for cooking a pizza is 400°C and the default air temperature range of the air inside the cooking chamber 105 is 480 °C - 520°C. For example, the temperature of the air inside the cooking chamber 105 is maintained at 500°C in the default mode. Because the upper 125 and lower 130 heating elements are controlled independently, it is possible to ensure that the cooking surface 110 reaches the target temperature whilst ensuring that the temperature of the air inside the cooking chamber is maintained at 500°C. The oven 100 also has a pizza presence detector 140, which is implemented on the controller 145, to determine whether a pizza 120 has been placed on the cooking support 115. In this example, the pizza presence detector 140 comprises program code executed by the controller and a temperature sensor 150 which gives a temperature dependent signal that is processed to determine the temperature to determine whether a pizza 120 has been placed on the cooking support 115. In other embodiments, the pizza presence detector 140 may detect a temperature of the cooking support 115 by other methods, for example using an alternative sensor and / or by inference or modelling of temperature. In other embodiments, the pizza presence detector 140 may detect whether a pizza is present by other methods, for example using weight. Thermostatic control using temperature sensor 150, which communicates with the pizza presence detector 140 of the controller 145, is used to control switching between the state of Figure 1a, the state of Figure 1b and the off configuration, to achieve and maintain these target temperatures. In other embodiments, the cooking pizza presence detector 140 may not be implemented on the controller 145 and instead may be implemented as a unitary component with the temperature sensor 150. Figure 1c also shows the oven 100 operating in the default mode. The door 155 is opened by the user when the user wants to insert a pizza into the oven 100 for cooking. Figure 1d shows the oven 100 operating in the cooking mode. The door 155 is closed once the pizza 120 is placed of the cooking support 115. In the cooking mode, the controller 145 operates the upper heating element 125 in the on state and the lower heating element 130 in the off state. This increases the temperature of the air inside the cooking chamber 105 to 900°C, which is optimal for cooking the top of the pizza 120 (e.g. melting the cheese and heating the toppings) in a short amount of time (e.g. 90 seconds). The heat from the upper heating element 125 cooks the top of the pizza 120 as the heats radiates directly onto the top of pizza (e.g. cheese and toppings). The base of the pizza 120 is cooked by the conduction of heat already stored in the cooking support 115. The temperature sensor 150 continuously takes measurements of the temperature of the cooking support 115 and transmits the temperature measurements to the pizza presence detector 140, which determines that the temperature of the cooking support 115 has decreased. As a result, the pizza presence detector 140 determines that there is pizza on the pizza stone 115, based on the temperature decrease and also taking into account which of the heating elements 125, 130 are on, and the controller 145 initiates operation of the upper heating element 125 in the cooking mode, as shown in Figure 1d. In other embodiments, the temperature sensor 150 measures the temperature of the cooking support 115 at regular intervals. The controller 145 is separated from the cooking chamber 105 by a wall 180, which insulates the controller 145 from the heat of the cooking chamber 105. Figure 2 is a flowchart of a method 200 according to an embodiment of the invention. In particular, method 200 is a method of operating the oven 100. The method 200 may be performed by the controller 145 using the pizza presence detector 140. The method 200 comprises measuring 205 a first temperature of the cooking support 215 and measuring 215 a second temperature of the cooking support 115. These measurements may be taken at regular intervals or may be continuous readings. The method 200 comprises determining 225 which heating elements are on. The method 200 comprises detecting 235 the presence of a pizza on the cooking support 115. In this method 200, this is achieved by detecting whether the temperature of the cooking support 115 has decreased between first and second temperature readings and by taking into account which of the heating elements is on. For example, the expected behaviour when the heating elements are on is that the temperature of the cooking support 115 would increase. Therefore, if the temperature of the cooking support 115 has decreased despite the heating elements being on, this is an indication that there is a pizza 120 on the cooking support 115 which is absorbing heat from the cooking support 115. Once the detection that there is a pizza on the cooking support is made, the controller initiates 245 operation of the heating components in the cooking mode. In this way, the operation of the heating components in the cooking mode depends on the detection that there is a pizza on the cooking support. Figure 3 illustrates another embodiment of a pizza oven, namely the pizza oven 300. The pizza oven 300 includes all of the features of pizza oven 100 and additionally includes a door sensor 360, which is a magnetic sensor in this example, though other types of sensors will be envisaged. The door sensor 360 determines whether the door 155 is open or closed and transmits this information to the pizza presence detector 140. The pizza presence detector 140 detects whether there is a pizza 120 on the cooking surface 110 taking into account whether the door 155 is open or closed, and possibly historic door opening / closure readings. When it is determined that the door was opened and then closed, the pizza presence detector 140 may detect that a pizza 120 is on the cooking support 110 and the controller 145 then initiates operation of the cooking mode. In the oven 300, the readings from the temperature sensor 150 are used to confirm that there is a pizza 120 on the cooking support 110, so that the controller 145 continues to operate the heating elements 125, 103 in the cooking mode when the temperature of the cooking support 115 is determined to be decreasing. In other embodiments of the oven 300, both the determination that the door 155 has been opened then closed and the determination that the temperature of the cooking support 115 is decreasing may be required to initiate operation of the cooking mode. In other embodiments, the oven 200 may not comprise the temperature sensor 150. In this way, the cooking mode is initiated in dependence on the determination that the door 155 has been opened then closed only. Figure 4 is a flowchart of a method 400 according to an embodiment of the invention. In particular, method 400 is a method of operating the oven 300. The method 400 may be performed by the controller 145 using the door sensor 360 and programmable code executed on the pizza presence detector 140. The method 400 comprises detecting 405 whether the door 155 is open or closed and detecting 415 the presence of a pizza on the cooking support based on the detection of whether the door 155 is open or closed. Once the detection that there is a pizza on the cooking support is made, the controller initiates 425 operation of the heating components in the cooking mode. The method 400 then comprises performing method steps 205, 215, 225 and 235 from the method 200 to confirm whether there is a pizza present on the cooking surface 115. When it is determined that there is pizza on the cooking support 115, the method step 435 includes continuing to operate in the cooking mode. In some embodiments of method 400, method step 225 is not performed. Figure 5 illustrates another embodiment of a pizza oven, namely the pizza oven 500. The pizza oven 500 is the same as the pizza oven 100 but includes a dial 570, functioning as the user input device. The dial 570 is used to indicate the type of pizza on the pizza stone 115. In this example, rotating the dial 570 to a position corresponding to 30° off set from the top vertical position corresponds to an input that the type of pizza is a Neapolitan pizza. Upon receiving this input, the controller 145 operates the pizza oven 500 in the cooking mode by operating the upper heating element 125 at full power. In the oven 500, the readings from the temperature sensor 150 are used to confirm that there is a pizza 120 on the cooking support 110, so that the controller 145 continues to operate the heating elements 125, 103 in the cooking mode when the temperature of the cooking support 115 is determined to be decreasing. In other embodiments of the oven 500, both the user input on the dial 570 and the determination that the temperature of the cooking support 115 is decreasing may be required to initiate operation of the cooking mode. In other embodiments, the oven 500 may not comprise the temperature sensor 150. In this way, the cooking mode is initiated in dependence on the user input on the dial 370 only. Figure 6 is a flowchart of a method 600 according to an embodiment of the invention. In particular, method 600 is a method of operating the oven 500. The method 600 may be performed by the controller 145 using the dial 570 and the pizza presence detector 140. The method 600 comprises detecting 605 a user input indicative of a pizza being placed on the cooking support 115 and detecting 615 the presence of a pizza on the cooking support based on the user input. Once the detection that there is a pizza on the cooking support is made, the controller initiates 625 operation of the heating components in the cooking mode. The method 600 then comprises performing method steps 205, 215, 225 and 235 from the method 200 to confirm whether there is a pizza present on the cooking surface 115. When it is determined that there is pizza on the cooking support 115, the method step 635 includes continuing to operate in the cooking mode. In some embodiments of method 600, method step 225 is not performed. Figure 7 illustrates another embodiment of a pizza oven, namely the pizza oven 700. The pizza oven 700 is the same as the pizza oven 100 but includes legs 790a, 790b and load sensors 795a, 795b. The load sensors 795a, 795b determine the weight of the oven 700 and transmits a data signal indicative of the weight to the pizza presence detector 140. The pizza presence detector 140 detects whether there is a pizza 120 on the cooking surface 110 taking into account the weight of the oven 400. The pizza presence detector 140 compares whether the weight of the oven 400 is greater than a pre-stored default weight or a previous historic weight reading. When it is determined that the weight of the oven 400 has increased, the pizza presence detector 140 may detect that a pizza 120 is on the cooking support 110 and the controller 145 then initiates operation of the cooking mode. In the oven 700, the readings from the temperature sensor 150 are used to confirm that there is a pizza 120 on the cooking support 110, so that the controller 145 continues to operate the heating elements 125, 103 in the cooking mode when the temperature of the cooking support 115 is determined to be decreasing. In other embodiments of the oven 700, both the determination that the weight of the oven has increased and the determination that the temperature of the cooking support 115 is decreasing may be required to initiate operation of the cooking mode. In other embodiments, the oven 700 may not comprise the temperature sensor 150. In this way, the cooking mode is initiated in dependence on the determination that the weight of the oven 700 has increased only. Figure 8 is a flowchart of a method 800 according to an embodiment of the invention. In particular, method 800 is a method of operating the oven 700. The method 800 may be performed by the controller 145 using the load sensors 790a, 790b and the pizza presence detector 140. The method 800 comprises detecting 805 a weight of the cooking support and any food supported thereon and detecting 815 the presence of a pizza on the cooking support based on the weight sensor measurement. For example, the weight detected by the load sensors 790a, 790b increases within a predetermined weight range when a pizza is present on the cooking support 115. Once the detection that there is a pizza on the cooking support is made, the controller initiates 825 operation of the heating components in the cooking mode. The method 800 then comprises performing method steps 205, 215, 225 and 235 from the method 800 to confirm whether there is a pizza present on the cooking surface 115. When it is determined that there is pizza on the cooking support 115, the method step 835 includes continuing to operate in the cooking mode. In some embodiments of method 800, method step 225 is not performed. Figure 9 is a schematic illustration of a controller 145 in accordance with an aspect of the present invention. The controller 145 comprises one or more processors 140 and a non-transitory computer readable memory 146. The non-transitory computer readable memory 146 stores instructions which, when executed by the one or more processors 140 causes operation of the methods described herein. The controller 145 transmits and / or exchanges data and / or control signals 147 with the other components of the oven 100, 300, 500, 700 such as the upper and lower heating elements 125, 130 and the door sensor 360. Figure 10a is a graphical representation of temperature changes of the cooking support according to an embodiment of the invention. The graph 1000 shows the changes in temperature of the pizza stone 115 of the oven 100, 300, 500 or 700. The time in seconds is shown on the x axis and the temperature of the cooking support is shown on the y axis. From Point A to Point B, the pizza stone 115 is heated up to a target temperature of 400 °C from 0 °C. At this time, the pizza stone 115 is heated by providing power to both the upper and lower heating elements 125, 130 in a suitable ratio, which may vary during this heat-up phase (i.e. the default mode). At point B, the pizza stone 115 is heated to the target temperature of 400 °C, so the upper and lower heating elements 125, 130 continue to operate in the default mode, which acts to maintain the temperature of the pizza stone 115 at the target temperature. At point C, a pizza is placed on the pizza stone 115. As a result, heat is transferred from the pizza stone 115 to the pizza to cook the pizza. Therefore, the temperature of the pizza stone 115 drops by a large amount whilst the pizza cooks. This is represented by the downwards line from Point C to Point D. During the time between Point C and Point D, the controller 145 is controlling the upper heating element 125 to be in the on state and the lower heating element 130 remains in the off state, so no heat is transferred to the pizza stone 115 from the lower heating element 130. The temperature sensor 150 takes a temperature measurement of the pizza stone 115 at two instances between Point C and Point D for the pizza presence detector 140 to determine if the temperature of the cooking support 115 is decreasing. The pizza presence detector 140 determines that there is a pizza present on the pizza stone 115 due to the decrease in temperature of the pizza stone 115. When the pizza is removed at Point D, the controller increases the power to the lower heating element 130 to ‘recharge’ (i.e. reheat) the pizza stone 115. In this way, the controller 145 operates the lower heating element 130 in the default mode. The power to the upper heating element will also be regulated to a suitable value for the cooking process. At Point E, the temperature of the pizza stone 115 is the same at the target temperature measured at Point B. Therefore, the controller 145 maintains the temperature of the cooking support 115 from Point E onwards to keep the pizza stone 115 consistently at the target temperature. Figure 10b is a graphical representation of temperature changes of the air inside the cooking chamber according to an embodiment of the invention. The graph 1100 shows the changes in temperature of the air inside the cooking chamber 105. The time in seconds is shown on the x axis and the temperature of the air inside the cooking chamber is shown on the y axis. From Point F to Point G, the air inside the cooking chamber 105 is heated up to a lower limit of 500 °C from 0 °C. The air temperature increases at a quicker rate than the pizza stone 115 temperature. At this time, the air inside the cooking chamber 105 is heated by primarily by the upper heating element 125, though power is provided to both the upper and lower heating elements 125, 130 in a suitable ratio, which may vary during this heat-up phase (i.e. the default mode). At Point G, the air inside the cooking chamber 105 reaches the lower limit of 500 °C, so the upper and lower heating elements 125, 130 continue to operate in the default mode, which acts to maintain the temperature of the air inside the cooking chamber 105 at the lower limit temperature. At Point H, a pizza is placed on the pizza stone 115 and so the controller 145 operates the oven in the cooking mode. The controller 145 operates the upper heating element 125 in the on state to quickly increase the temperature of the air inside the cooking chamber 105 to the upper limit of 900 °C to fully cook the pizza. This is represented by the upwards line from Point H to Point I. At Point I, the temperature of the air inside the cooking chamber has reached 900 °C and so the controller 145 operates the upper heating element 125 in the cooking mode to maintain the upper limit temperature of the air inside the cooking chamber 105 of 900 °C. At Point J the pizza 120 is cooked and the door 155 is opened to remove the pizza 120 from the oven 100. The opening of the door 155 results in a rapid decrease in the temperature of the air inside the cooking chamber 105 to below the lower limit as shown between Point J and Point K. The controller 145 then operates the upper and lower heating elements 125, 130 in the default mode to bring the temperature of the air inside the cooking chamber 105 back up to the lower limit of the air inside the cooking chamber at Point L. After Point L, the controller 145 continues to operate in the default mode to maintain the temperature of the air inside the cooking chamber 105 at the lower limit. Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of them mean “including but not limited to”, and they are not intended to and do not exclude other components, integers, or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise. Features, integers, characteristics, or groups described in conjunction with a particular aspect, embodiment, or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and / or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1. A pizza oven comprising: a controller;a cooking chamber comprising a cooking support configured to support a pizza whilst cooking;a first heating component configured to heat the upper surface of the cooking support by radiation;a second heating component configured to heat the cooking support;a pizza presence detector configured to detect whether there is a pizza on the cooking support; andwherein the controller is configured to operate at least one of the first and second heating components, in accordance with, at different times:a default mode, anda cooking mode, the operation of which depends on the detection of a pizza on the cooking support by the pizza presence detector.

2. The pizza oven of claim 1, wherein an average power provided to the first heating component in the cooking mode is greater than an average power provided to the first heating component in the default mode.

3. The pizza oven of claim 1 or claim 2, wherein an average power provided to the second heating component in the default mode is greater than an average power provided to the second heating component in the cooking mode.

4. The pizza oven of any preceding claim, wherein, in the default mode, the controller is configured to control the second heating component to maintain a temperature of the cooking support to within a threshold of a target temperature of the cooking support.

5. The pizza oven of any preceding claim, wherein, in the cooking mode, the controller is configured to control the first heating component to draw a maximum power.

6. The pizza oven of any preceding claim, wherein the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on at least one of: (i) detection of presence of a pizza on the cooking support and (ii) a user input, optionally wherein the pizza presence detector comprises one or more sensors configured to detect a pizza on the cooking support.

7. The pizza oven of claim 6, wherein:the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support;the one or more sensors comprise a weight sensor configured to measure a weight of the cooking support and any food supported thereon; and the pizza presence detector is configured to detect whether there is a pizza on the cooking support in dependence on the weight of the cooking support and any food supported thereon.

8. The pizza oven of claim 6, wherein:the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support;the one or more sensors comprise a temperature sensor;the pizza presence detector is configured to detect whether there is a pizza on the cooking support in dependence on the measured temperature.

9. The pizza oven of claim 6, wherein:the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support;the pizza oven comprises an openable door to provide access to the cooking support and the one or more sensors comprise a door sensor configured to determine whether the door is open or closed; andthe pizza presence detector is configured to detect the presence of a pizza on the cooking support by taking into account whether the door is open or closed, as determined by the door sensor.

10. The pizza oven of claim 6, wherein the controller is configured to initiate operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (ii) the user input and the pizza presence detector is configured to: confirm whether a pizza is present on the cooking support, and the controller is configured to:continue operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on confirmation that a pizza is present on the cooking support; andterminate operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on the absence of confirmation that a pizza is present on the cooking support.

11. The pizza oven of claim 7 to 9, wherein the pizza presence detector is configured to: confirm whether a pizza is present on the cooking support, and the controller is configured to:continue operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on confirmation that a pizza is present on the cooking support; and terminate operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on the absence of confirmation that a pizza is present on the cooking support.

12. The pizza oven of claim 10 or claim 11, wherein at least one of the one or more sensors are used in the confirmation that a pizza is present on the cooking support.

13. The pizza oven of any preceding claim, wherein at least one of the first and second heating components is an electrically-powered radiative heating element, optionally wherein the cooking support comprises a pizza stone.

14. A method of operating a pizza oven, the pizza oven comprising a cooking chamber comprising a cooking support configured to support a pizza whilst cooking, a first heating component and a second heating component, wherein the method comprises:detecting whether there is a pizza on the cooking support; andoperating at least one of the first and second heating components, in accordance with, at different times:a default mode, anda cooking mode, the operation of which depends on the detection of a pizza on the cooking support.

15. The method of operating a pizza oven of claim 14, comprising providing a greater average power to the first heating component in the cooking mode than an average power provided to the first heating component in the default mode.

16. The method of operating a pizza oven of claim 14 or claim 15, comprising providing a greater average power to the second heating component in the default mode than an average power provided to the second heating component in the cooking mode.

17. The method of operating a pizza oven of any of claims 14 to 16, comprising, in the default mode, controlling the second heating component to maintain a temperature of the cooking support to within a threshold of a target temperature of the cooking support.

18. The method of operating a pizza oven of any of claims 14 to 17, comprising, in the cooking mode, controlling the first heating component to draw a maximum power.

19. The method of operating a pizza oven of any of claims 14 to 18, comprising initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on at least one of: (i) detection of presence of a pizza on the cooking support and (ii) a user input, optionally wherein the method comprises detecting a pizza on the cooking support using one or more sensors configured to detect a pizza on the cooking support.

20. The method of operating a pizza oven of claim 19, wherein the method comprises:initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support;measuring a weight of the cooking support and any food supported thereon; anddetecting whether there is a pizza on the cooking support in dependence on the weight of the cooking support and any food supported thereon.

21. The method of operating a pizza oven of claim 19, wherein the method comprises:initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support;measuring a temperature of the cooking support; anddetecting whether there is a pizza on the cooking support in dependence on the measured temperature.

22. The method of operating a pizza oven of claim 19, wherein the method comprises:initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (i) detection of presence of a pizza on the cooking support;determining whether an openable door of the oven is open or closed, wherein the door provides access to the cooking support; anddetecting the presence of a pizza on the cooking support by taking into account whether the door is open or closed, as determined by the door sensor.

23. The method of operating a pizza oven of any of claims 20 to 22, wherein measuring the weight of the cooking support and any food supported thereon, measuring the temperature of the cooking support or determining whether the door of the oven is open or closed comprising using the one or more sensors.

24. The method of operating a pizza oven of claim 19, comprising:initiating operation of at least one of the first and second heating components in accordance with the cooking mode in dependence on (ii) the user input;confirming whether a pizza is present on the cooking support;continuing operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on confirmation that a pizza is present on the cooking support; andterminating operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on the absence of confirmation that a pizza is present on the cooking support.

25. The method of operating a pizza oven of any of claims 20 to 23, comprising: confirming whether a pizza is present on the cooking support;continuing operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on confirmation that a pizza is present on the cooking support; andterminating operation of the at least one of the first and second heating components in accordance with the cooking mode in dependence on the absence of confirmation that a pizza is present on the cooking support.

26. The method of operating a pizza oven of claim 24 or claim 25, wherein confirming whether a pizza is present on the cooking support comprises using the one or more sensors.

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