EP3508032B1

EP3508032B1 - A fermentation unit

Info

Publication number: EP3508032B1
Application number: EP17754330.3A
Authority: EP
Inventors: Haluk Karatas; Levent Akdag; Bekir Ozyurt
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2016-09-02
Filing date: 2017-08-14
Publication date: 2020-04-08
Anticipated expiration: 2037-08-14
Also published as: WO2018041612A1; EP3508032A1; TR201612443A2

Description

The present invention relates to an improved fermentation unit that is suitable for use in a microwave oven.
Nowadays, the effect of a healthy diet on the improvement of quality of human life is proven, and milk and dairy products constitute an indispensable part of the nutrition recipes. Cleansing of milk as an animal food from bacteria that may cause harm to human health before consumption bears great importance. It is possible to cleanse milk from harmful bacteria by heating and cooling the milk to certain temperatures by primitive and/or advanced pasteurization methods. To boil and then cool the milk in household environments, that can be considered as one of the primitive pasteurization methods, is a widely used method. The most efficient way of pasteurization is provided in professional environments where the milk is rapidly heated to high temperature degrees and then rapidly cooled. With the fermentation of the milk cleansed of harmful bacteria, it is possible to easily produce cheese and yogurt that are fit for consumption.
Fermentation is decomposition of a substance chemically, generally by way of inducing heat, through the medium of various unicellular bacteria, fungi and other microorganisms that can be generalized as yeast. The structure of the material to be produced with the fermentation of the milk is affected by the type of the yeast and the process being carried out at an environment at specific temperatures required for the chemical reaction. Although it is possible to perform the said process in a household environment by keeping the contact with air at minimum, various automation applications have been developed since it is difficult and requires too much time to meet certain requirements such as adjustment of the quantity of the material, keeping the temperature stable, ensuring a standard product quality through meeting the same conditions at each fermentation, etc.
In the state of the art Japanese Patent Document No. JP08110054 , a method for fermentation of milk to produce yogurt is disclosed. In the said method, a microwave oven is used as a source of heat to provide the fermentation. Although the heating period is shortened, no function related to the pasteurization of the milk is present.
In the state of the art Korean Patent Document No. KR1020050009011 , heating the milk and bringing the fermentation to the optimum fermentation working temperature is disclosed. In the said embodiment, however, after the milk is heated, yeast is manually added by the user to the milk and the milk is put back into the heater.
To perform the pasteurization and the fermentation processes that must be controlled by the user so as to achieve a certain standard product quality becomes difficult because of too many factors. Moreover, it takes a considerable time for the user who must be active during the entire process.
A prior art fermentation unit is disclosed in document WO 2007/035068 .
The aim of the present invention is the realization of a fermentation unit suitable for use in a microwave oven, that provides automatic pasteurization and fermentation.
The fermentation unit realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, comprises a body; a cover that covers the body; a receptacle that is placed on the cover so as to extend into the body and wherein yeast is put; an intermediate cover that divides the receptacle into two compartments as upper and lower compartments, and a bottom cover that is disposed at the base of the receptacle and that enables the material in the lower compartment to be emptied into the body. The intermediate cover opens at a first limit temperature predetermined by the manufacturer and enables the material in the upper compartment to be emptied into the lower compartment. The bottom cover opens at a predetermined second limit temperature and enables the material in the lower compartment to be emptied into the body. At room temperature (20 to 25 centigrade degrees), the bottom cover and the upper cover are in the closed position. The user puts the material containing the yeast into the upper compartment. The material containing the yeast varies depending on the product desired to be obtained. A material containing a different cheese yeast culture can be used for various cheese varieties or a yeast content can be used for making yogurt. Milk is added to the body section. In order to enable the user to easily determine the quantity, various quantity indicators can be provided on the body and the receptacle. The cover of the fermentation unit is closed and the fermentation unit is placed into the microwave unit. The milk is heated to high temperature values to kill the harmful bacteria in the milk. Milk boils at approximately 100.1 centigrade degrees under ideal conditions. Being heated to the said temperature, the milk is cleansed of the harmful bacteria therein. The ideal temperature for fermentation is between 40 and 45 centigrade degrees. The predetermined temperatures for opening the bottom cover and the upper cover are determined based on these values. The first limit temperature is a temperature value higher than the second limit temperature. It is aimed to heat the milk up to the boiling temperature to cleanse the same from harmful bacteria in the first stage and then to provide the blending of the yeast and the milk at the ideal temperature for fermentation. Since the ideal temperature for fermentation is also reached while boiling the milk, the bottom cover would open at these temperatures and if there is yeast in the lower compartment, the milk would blend with the yeast before the milk is boiled and the heating process would continue until the boiling point. In order to prevent this, the material containing the yeast is put into the upper compartment and when the bottom cover opens at the fermentation temperature, the material containing the yeast is prevented from blending with the milk since the intermediate cover is closed. The values that are close to the boiling temperature are the values defined for opening the intermediate cover. When the intermediate cover opens, the material containing the yeast passes to the lower compartment. When the milk is boiled and cleansed of harmful bacteria, the heating process stops and when the ambient temperature reaches the appropriate temperature for fermentation, the bottom cover opens and the milk blends with the yeast. The ambient temperature is kept at optimum values until the end of the fermentation process. The fermentation unit is produced from a material suitable for heating in a microwave oven. Thus, the heating process can be performed in a microwave oven. By defining the said heating steps in the cooking options of the microwave oven, the embodiment can be realized. Thus, the user only places the material containing the yeast and the milk into the fermentation unit and the milk is automatically pasteurized and fermented.
In an embodiment of the present invention, the receptacle is produced from a material that is impermeable to microwave. The microwave passes through solid surfaces and vibrates the molecules of the liquid contained in the substance and thus provides the heating. Solid matters produced by using some special materials prevent passage of microwaves. Thus, the effect of the microwave on an object beyond the said material is prevented. The body is produced from a material that is permeable to microwave since it is aimed to heat the material put therein; however, since the yeast put into the receptacle is a living organism, when exposed to high temperatures, the yeast dies and fermentation does not occur. In order to protect the yeast from high temperatures, the yeast is put into a receptacle that is produced from a microwave-impermeable material. Thus, since the microwaves do not reach the yeast, the yeast stays alive.
In an embodiment of the present invention, a first switch is provided, that enables the intermediate cover to be opened when the temperature of the liquid in the body reaches the first limit temperature. The first switch has an active position wherein the first switch enables the intermediate cover to remain in the closed position at the temperatures except for the first limit temperature and a passive position to which the first switch is changed by being opened upon reaching the first limit temperature and wherein the intermediate cover is enabled to be opened. After shifting to the passive position when the temperature of the liquid inside the body reaches the first limit value, the first switch shifts back to the active position when the temperature changes, thus enabling the intermediate cover to be closed.
In an embodiment of the present invention, the first switch is produced from a shape memory alloy. The shape memory alloys are alloys that change shape when subjected to a certain external force in the martensitic state and that regain their original shapes to a great extent after shifting to the austenite phase temperature. The first switch is produced from a shape memory alloy of which austenite phase temperature is equal to the first limit temperature. The shape taken by the first switch at the first limit temperature enables the first switch to shift to the passive position so as to open the intermediate cover. The first switch shifts to the active position where the latter is in the martensitic state at temperatures except the said temperature, thus the intermediate cover is closed. Thus, The material containing the yeast is enabled to change compartment depending on the temperature values.
In an embodiment of the present invention, a first switch is provided, that enables the intermediate cover to be opened/closed according to the data received from a temperature sensor disposed in the body. When the liquid in the body reaches the first limit temperature, the temperature sensor enables the first switch to be opened so as to bring the same to the passive position. With the shifting of the first switch to the passive position, the intermediate cover opens such that the material passes from the upper compartment to the lower compartment. Thus, transition from the pasteurization step to the fermentation step is provided without the need for intervention of the user.
In another embodiment of the present invention, the first switch enables the intermediate cover to be kept open when the temperature of the liquid put into the body is within the range of 60 to 100 centigrade degrees. In this case, the first limit temperature defines not a single temperature but a range of temperature. The first switch shifts to the passive position when the temperature of the liquid in the body reaches 60 centigrade degrees and enables the intermediate cover to be opened. Determination of the temperature degree is based on a temperature value above the second limit temperature. Thus, when the second limit temperature is reached during the heating process for boiling the milk, the first switch remains in the closed position. The material containing the yeast is still kept in the upper compartment and prevented from blending with the milk at a high temperature.
In an embodiment of the present invention, a second switch is provided, that enables the bottom cover to be opened when the liquid in the body reaches the second limit temperature. The second switch has an active position wherein the second switch enables the bottom cover to remain in the closed position at the temperatures except for the second limit temperature and a passive position to which the second switch is changed by being opened upon reaching the second limit temperature and wherein the bottom cover is enabled to be opened. After shifting to the passive position when the temperature of the liquid inside the body reaches the second limit temperature value, the second switch shifts back to the active position when the temperature changes, thus enabling the bottom cover to be closed.
In an embodiment of the present invention, the second switch is produced from a shape memory alloy. The shape taken by the second switch at the second limit temperature enables the second switch to shift to the passive position so as to open the bottom cover. At the temperatures except for the second limit temperature, the second switch returns to its shape at the room temperature and shifts to the active position, thus enabling the bottom cover to be closed. Thus, since the bottom cover is in the closed position at the first limit temperature, when the material containing the yeast is emptied upon the opening of the intermediate cover, the material containing the yeast is prevented from blending with the liquid inside the body.
In an embodiment of the present invention, a second switch is provided, that enables the bottom cover to be opened/closed according to the data received from a temperature sensor disposed in the body. With the shifting of the second switch to the passive position, the bottom cover opens such that the material passes from the upper compartment to the lower compartment.
In another embodiment of the present invention, the second switch enables the bottom cover to be kept open when the temperature of the liquid put into the body is within the range of 40 to 50 centigrade degrees. In this case, the second limit temperature defines not a single temperature but a range of temperature. The second switch shifts to the passive position when the temperature of the liquid in the body reaches 40 centigrade degrees and enables the bottom cover to be opened. Determination of the temperature degree is based on a temperature value that is optimum for fermentation and does not overlap with the first limit temperature. Thus, during the heating process for boiling the milk, when the first switch opens, the material containing the yeast will not be present in the lower compartment, and since the bottom cover will be closed before the second limit temperature is reached, the material will be kept in the lower compartment until the temperature of the liquid reaches the second limit temperature.
In an embodiment of the present invention, on the section of the receptacle remaining on the cover an opening is provided, that enables the material to be placed into the receptacle. The opening is covered with a top cover. Before the fermentation unit is placed into the heater, the material containing the yeast is placed through the opening into the receptacle and isolated from the outer environment by means of the top cover. The top cover is produced from the same material as the receptacle. Thus, since, when used in a microwave oven, the top cover prevents microwaves from passing therethrough, the material in the receptacle is prevented from heating up.
In an embodiment of the present invention, the microwave oven comprises the fermentation unit. The programs necessary for heating the fermentation unit to the required temperature values can be set by the manufacturer of the microwave oven.
By means of the present invention, both pasteurization and fermentation of the milk are performed automatically without the need for direct intervention of the user.
The fermentation unit realized in order to attain the aim of the present invention is illustrated in the attached figure, where:

Figure 1 - is the front view of the fermentation unit.

The elements illustrated in the figures are numbered as follows:

1. Fermentation unit
2. Body
3. Cover
4. Receptacle
5. Intermediate cover
6. Bottom cover
7. Top cover
8. Upper compartment
9. Lower compartment
10. First switch
11. Second switch
12. Temperature sensor
13. Opening

The fermentation unit (1) comprises a body (2) which is suitable for placing liquid therein; a cover (3) that covers the body (2); a receptacle (4) that is placed on the cover (3) so as to extend into the body (2); an intermediate cover (5) that divides the receptacle (4) into two compartments, namely a lower compartment (9) and an upper compartment (8) and that opens at a first limit temperature (T1) predetermined by the manufacturer so as to enable the material in the upper compartment (8) to be emptied into the lower compartment (9), and a bottom cover (6) that is disposed at the base of the receptacle (4) and that opens at a second limit temperature (T2) predetermined by the manufacturer so as to enable the material in the lower compartment (9) to be emptied into the body (2). The fermentation unit (1) is designed as suitable for use in a microwave oven. Milk is put into the body (2) and the cover (3) is closed by the user. The material to be fermented is placed into the receptacle (4) on the cover (3). The first limit temperature (T1) is determined by the manufacturer above the ideal fermentation temperature, between the values close to the boiling point of the milk. The second limit temperature (T2) is determined by the manufacturer at values close to the ideal fermentation temperature. These two temperature values (T1 and T2) are above the room temperature (20 to 25 centigrade degrees). Given that the process is performed at the room temperature, the intermediate cover (5) and the bottom cover (6) are in the closed position while the milk and the material containing the yeast are loaded. Thus, the material containing the yeast stays in the upper compartment (8). After the milk and the material containing the yeast are placed, the fermentation unit (1) is placed into the microwave oven and the heating process is started for pasteurization. When the first limit temperature (T1) is reached, the intermediate cover (5) is opened and the material containing the yeast passes to the lower compartment (9). After the temperature necessary for the pasteurization is reached, the heating process is ended and the milk starts to cool. When the temperature of the milk drops to the second limit temperature (T2), the bottom cover (6) is opened and the material containing the yeast is emptied into the body (2) and blended with the milk (Figure 1).
The fermentation unit (1) of the present invention comprises the receptacle (4) produced from a material impermeable to microwave. Thus, since the material containing the yeast placed in the receptacle (4) is in a microwave-impermeable medium, the said material is not affected by the heating of the milk in the body (2).
In an embodiment of the present invention, the fermentation unit (1) comprises a first switch (10) that enables the intermediate cover (5) to be opened when the temperature of the liquid inside the body (2) reaches the first limit temperature (T1). The first switch (10) has an active position wherein the first switch (10) enables intermediate cover (5) to be kept closed and a passive position wherein the first switch (10) enables intermediate cover (5) to be kept open. The shifting between the active and passive positions takes place depending on the first limit temperature (T1). When the first limit temperature (T1) is reached, the first switch (10) shifts to the passive position and enables the intermediate cover (5) to be opened, and thus the material containing the yeast in the upper compartment (8) is delivered to the lower compartment (9). The first switch (10) is shifted to the active position at temperatures except for the first limit temperature (T1) and thus the intermediate cover (5) is kept closed. Thus, the material containing the yeast is prevented from blending with milk at high temperatures where the material may spoil.
In an embodiment of the present invention, the fermentation unit (1) comprises the first switch (10) that is produced from a shape memory alloy. The first switch (10) is designed so as to enable the intermediate cover (5) to be in the open position at the first limit temperature (T1). At a temperature except for the first limit temperature (T1), the first switch (10), that changes phase depending on the temperature change, takes a shape that enables the intermediate cover (5) to be in the closed condition. The first switch (10) changes position between the active and passive positions depending on the temperature change. Thus, since the material containing the yeast is delivered from the upper compartment (8) to the lower compartment (9) after the process of heating of the milk is completed, the material containing the yeast is prevented from blending with milk at high tem peratures.
In an embodiment of the present invention, the fermentation unit (1) comprises a temperature sensor (12) that is disposed in the body (2). The first switch (10) enables the intermediate cover (5) to be opened/closed according to the data received from the temperature sensor (12). The temperature sensor (12) detects the temperature of the milk in the body (2) and, when the first limit temperature (T1) is reached, triggers the first switch (10) so as to enable the intermediate cover (5) to be opened. Being disposed in the body (2), the temperature sensor (12) measures the temperature value therein and enables the intermediate cover (5) in the receptacle (4) that is not affected from the heat to be opened, thus enabling the material containing the yeast to be preserved at high temperature values without getting spoiled.
In an embodiment of the present invention, the fermentation unit (1) comprises the first switch (10) that enables the intermediate cover (5) to be kept open when the temperature of the liquid put into the body (2) is within the range of 60 to 100 centigrade degrees. The first limit temperature (T1) is determined depending on the boiling point of the milk that must be reached for pasteurization of the milk and on the second limit temperature (T2) values. The second limit temperature (T2) is determined at the ideal temperature value required for the fermentation. Given that the ideal temperature for fermentation is between 40 and 50 centigrade degrees, the values at which the second switch (11) is in the closed position must be taken into account. Since exceeding the boiling temperature required for pasteurization decomposes the structure of the milk and consumes unnecessary energy, it is sufficient to limit the said temperature at just above 100 degrees.
In an embodiment of the present invention, the fermentation unit (1) comprises a second switch (11) that enables the bottom cover (6) to be opened when the temperature of the liquid inside the body (2) reaches the second limit temperature (T2). The second switch (11) is in the active position where the bottom cover (6) is in the closed position at temperatures except for the second limit temperature value (T2). When the temperature of the liquid contained in the body (2) reaches the second limit temperature (T2), the second switch (11) switches to the passive position and enables the bottom cover (6) to be opened. Thus, the material containing the yeast present in the bottom compartment (9) is emptied onto the milk in the body (2). The second limit temperature (T2) is determined at the ideal temperature value required for the fermentation. Thus, the material containing the yeast and the milk are enabled to be blended under the most appropriate conditions.
In an embodiment of the present invention, the fermentation unit (1) comprises the second switch (11) that is produced from a shape memory alloy. The second switch (11) is designed so as to enable the bottom cover (5) to be in the open position at the second limit temperature (T2). At a temperature except for the second limit temperature (T2), the second switch (11), that changes phase depending on the temperature change, takes a shape that enables the bottom cover (6) to be in the closed condition. The second switch (11) changes position between the active and passive positions depending on the temperature change. Thus, since the material containing the yeast is emptied from the lower compartment (9) into the body (2) after the process of heating of the milk is completed and blended with milk at the ideal fermentation temperature, the fermentation is ensured.
In an embodiment of the present invention, the fermentation unit (1) comprises a temperature sensor (12) that is disposed in the body (2) and the second switch (11) that enables the bottom cover (6) to be opened/closed according to the data received from the temperature sensor (12). The second switch (11) enables the bottom cover (6) to be opened/closed according to the data received from the temperature sensor (12). The temperature sensor (12) detects the temperature of the milk in the body (2) and, when the second limit temperature (T2) is reached, triggers the second switch (11) so as to enable the bottom cover (6) to be opened. Being disposed in the body (2), the temperature sensor (12) measures the temperature value therein and enables the bottom cover (6) in the receptacle (4) that is not affected from the heat to be opened, thus enabling the material containing the yeast to be preserved at high temperature values without getting spoiled. Thus, the material containing the yeast is enabled to be blended with the milk at the second limit temperature value (T2) and the fermentation is performed under ideal conditions.
In an embodiment of the present invention, the fermentation unit (1) comprises the second switch (11) that enables the bottom cover (6) to be kept open when the temperature of the liquid put into the body (2) is within the range of 45 to 50 centigrade degrees. The second limit temperature (T2) is determined based on the temperature of 40-50 centigrade degrees which is ideal for fermentation. The second switch (11) enables the bottom cover (6) to be kept closed at temperatures except for the said values and thus the milk and the material containing the yeast are prevented from blending at high temperatures. Since the second limit temperature (T2) values are also exceeded in the process of heating performed in the first step in order to reach the boiling temperature of the milk that is required to be reached for the pasteurization of the milk, the bottom cover (6) is also opened during this process. However, since the material containing the yeast is placed into the upper compartment (8) and its passage to the lower compartment (9) is provided when the first limit temperature (T1) is reached, the material containing the yeast is not present in the lower compartment (9) during the first heating process. When the second limit temperature (T2) is reached again when the heating process is stopped after the pasteurization process is completed and the temperature is decreased, the second switch (11) shifts to the passive position and the bottom cover (6) is enabled to be opened. Thus, the materials are blended at the ideal fermentation temperature without the need for intervention of the user.
In an embodiment of the present invention, the fermentation unit (1) comprises an opening (13) that is provided on the section of the receptacle (4) remaining on the cover (3) and that enables the material to be placed into the receptacle (4), and a top cover (7) that covers the opening (13). The opening (13) is provided on the upper part of the receptacle (4) in order to enable the material to be placed into the receptacle (4) that is positioned into a cavity arranged on the cover (3), passing through the cover (3) and extending into the body (2) so as to be suspended over the cover (3). Since the fermentation unit (1) is placed into the microwave oven after the materials are placed therein, the opening (13) must be closed with the top cover (7) that is impermeable to microwave. Thus, since the material containing the yeast placed put into the receptacle (4) is not exposed to microwave, the material is prevented from heating up. Moreover, the user is enabled to easily put material into the receptacle (4) when the cover (3) is closed.
In an embodiment of the present invention, the microwave oven comprises the fermentation unit (1). The microwave oven can be programmed so as to provide the heating processes required for ideal operation of the fermentation unit (1). Thus, the user selects the fermentation program and all the processes are performed in a time and temperature controlled manner without the need for any further intervention of the user.
By means of the present invention, a fermentation unit (1) that can perform all the processes required for pasteurization and fermentation of the milk without intervention of the user is realized and thus ease of use as well as a standard quality of the resulting fermented product are provided.

Claims

A fermentation unit (1) suitable for use with a microwave oven, comprising a body (2) that is suitable for placement of liquid therein; a cover (3) that covers the body (2); a receptacle (4) that is placed on the cover (3) so as to extend into the body (2), characterized by
- an intermediate cover (5) that divides the receptacle (4) into two compartments, namely a lower compartment (9) and an upper compartment (8) and that opens at a first limit temperature (T1) predetermined by the manufacturer so as to enable the material in the upper compartment (8) to be emptied into the lower compartment (9), and

- a bottom cover (6) that is disposed at the base of the receptacle (4) and that opens at a second limit temperature (T2) predetermined by the manufacturer so as to enable the material in the lower compartment (9) to be emptied into the body (2).
A fermentation unit (1) as in Claim 1, characterized by the receptacle (4) that is produced from a microwave-impermeable material.
A fermentation unit (1) as in Claim 1 or 2, characterized by a first switch (10) that enables the intermediate cover (5) to be opened when the temperature of the liquid in the body (2) reaches the first limit temperature (T1).
A fermentation unit (1) as in Claim 3, characterized by the first switch (10) that is produced from a shape memory alloy.
A fermentation unit (1) as in Claim 3, characterized by a temperature sensor (12) that is disposed in the body (2) and the first switch (10) that enables the intermediate cover (5) to be opened/closed according to the data received from the temperature sensor (12).
A fermentation unit (1) as in any one of Claim 4 or 5, characterized by the first switch (10) that enables the intermediate cover (5) to be kept open when the temperature of the liquid put into the body (2) is within the range of 60 to 100 centigrade degrees.
A fermentation unit (1) as in Claim 1 or 2, characterized by a second switch (11) that enables the bottom cover (6) to be opened when the temperature of the liquid in the body (2) reaches the second limit temperature (T2).
A fermentation unit (1) as in Claim 7, characterized by the second switch (11) that is produced from a shape memory alloy.
A fermentation unit (1) as in Claim 7, characterized by the temperature sensor (12) that is disposed in the body (2) and the second switch (11) that enables the bottom cover (6) to be opened/closed according to the data received from the temperature sensor (12).
A fermentation unit (1) as in any one of Claim 8 or 9, characterized by the second switch (11) that enables the bottom cover (6) to be kept open when the temperature of the liquid put into the body (2) is within the range of 40 to 50 centigrade degrees.
A fermentation unit (1) as in any one of the above claims, characterized by an opening (13) that is provided on the section of the receptacle (4) remaining on the cover (3) and that enables the material to be placed into the receptacle (4), and a top cover (7) that covers the opening (13).
A microwave oven comprising a fermentation unit (1) as in any one of the above claims.