JPWO2013039007A1 - Flyer - Google Patents

Abstract

The present invention relates to a fryer and a deep-fried cooking method in which deterioration of oil is suppressed, the flavor of fried food is good, the environment in the kitchen is good, and the work associated with cooking is safe. A heater (2c) is provided in the middle part of the oil tank (2), the upper part from the heater (2c) is a high-temperature oil tank (2b), the lower part is a low-temperature oil tank (2g), and the oil tank bottom (2h) is an accumulation part (2i) From the low temperature region sensor (2r) to the accumulation portion (2i) provided at the bottom of the oil tank (2h) as a low temperature region, and the discharge pipe (2n) is provided with an on-off valve (2k). The entire low temperature oil tank (2g) from the convection prevention part (2e) is surrounded by a water tank (3), and a water injection pipe (3a), a water injection opening / closing device (3e), and an overflow discharge pipe (3b) are provided. And flyer. And it is a fried cooking method characterized by setting the oil temperature in the low temperature region to 80 ° C. or less, precipitating fried residue and moisture, and discharging continuously or intermittently together with oil during cooking, or storing until cooking is completed. .

Description

  The present invention relates to a fryer that is a deep-fried cooker and a deep-fried cooking method.

Common fryer for fried cooking includes a self-supporting type and a table type, and the heating method of the heater is mainly a gas combustion tube method and a heating wire method. These general fryer have a basic structure with a heater in the middle of the oil tank, the upper part is a high-temperature oil tank for cooking, and the lower part is a low-temperature oil tank. Air is sucked from the lower part to cool the low temperature oil tank and the casing.
In addition, these general fryer can be caused by cooking and fried carbonized over time adheres to the ingredients in the high-temperature oil tank, impairs the flavor of the ingredients, and does not suppress the deterioration of the oil, thus reducing the frequency of oil replacement There is a problem that it cannot be performed, there is a risk of splashing oil, a large amount of water vapor generated by cooking, oil mist and exhaust heat, an adverse effect on the surrounding environment, and a large cleaning burden in the kitchen and the housing.

  Furthermore, in cooking where a large amount of fried residue is generated, there is a danger of ignition if the fried residue is accumulated until it approaches the heater, and it is necessary to remove it. The work is a high-temperature work both in the method of removing the frying residue from the cooking oil surface of the fryer and in the method of removing the frying residue and all the oil from the bottom discharge port and removing it with a filtration device, etc. It is dangerous because the water that has settled with the fried residue splashes on the oil in the high-temperature oil tank, generating steam, oil mist, and smoke, and the removed fried residue is carbonized and the temperature is high. There was a problem of spontaneous ignition if left unattended. In addition, fires caused by spontaneous firing of fried casks are frequent in restaurants, food supermarkets, etc., and there are many reports from fire departments, and there are very many people involved in kitchen work who experienced fires and smoke that did not lead to fires.

  Patent Document 1 discloses a fryer that suppresses generation of polar compounds caused by oil deterioration and automatically purifies cooking oil. In the fryer of Patent Document 1, water is stored in the lower part of the oil tank, circulated between a tank provided separately from the oil tank, and the frying residue and water are dropped into the water in the lower part of the oil tank, and the recovered fried dregs collected in the water tank by circulation. It has a mechanism that automatically discharges to the outside. However, in the flyer of this structure, the price has increased due to the complexity of the mechanism, the discharged fried waste contains a large amount of water mixed with oil and is difficult to handle, and the oil spills often when mixed with water. In a bad environment where a large amount of water, oil and fried residue are mixed, there is a problem that the fried residue cannot be removed stably.

JP 2008-200222 A

  The present invention suppresses the deterioration of the oil used, improves the flavor of fried foods, lowers the frequency of oil replacement, further reduces oil splashes, water vapor, oil mist and oil smoke, and exhaust heat, and the environment in the kitchen is good. An object of the present invention is to provide a fryer and a deep-fried cooking method that can reduce the burden of cleaning, prevent spontaneous combustion of fried residue, and can safely work with cooking.

The present invention
1) A fryer with an oil tank and a heater in the middle of the oil tank, a high temperature oil tank at the top and a low temperature oil tank below the heater, the low temperature oil tank having a cooling tank and / or a cooling pipe, The flyer of the 1st structure characterized by the lower part of having an inclination and a low-temperature area | region.
2) The fryer of the first configuration, characterized in that it has a pipe and / or a valve or a plug for discharging fried residue and moisture from a low temperature region.
3) The flyer having the first or second configuration, wherein a structure having a gap with an opening ratio of 20 to 80% with respect to a horizontal cross-sectional area of the oil tank is provided in a low-temperature oil tank at least 3 mm below the lower end of the heater. A flyer of the third configuration characterized by that.
4) A heater is provided in the middle of the oil tank, and during cooking in the high-temperature oil tank above the heater, the oil in the low-temperature oil tank below the heater is indirectly brought into contact with water, so that the oil temperature in the low-temperature region is 80 ° C. A fried cooking method characterized in that fried residue and moisture are precipitated in a low temperature region and discharged continuously or intermittently with oil or stored until the end of cooking.
It is.

The oil tank of the present invention is usually made of stainless steel because of its rust prevention performance and ease of processing, but may be iron, copper, aluminum and alloys containing them, ceramic or heat-resistant resin. A combination of using ceramic or stainless steel with low conductivity and high heat resistance and using copper or aluminum with high thermal conductivity in the low temperature oil tank may be used.
The oil tank is fixed at a predetermined position by a structure, and this structure has a skeletal structure, is covered with a box-shaped housing, and has a structure having a door on the front surface portion. However, it does not have a skeletal structure, and the strength may be maintained by the casing and oil tank, there is no skeletal structure and no casing, the oil tank itself is the main part of the structure, the oil tank itself has a heater, legs, temperature display panel, etc. A support structure may be provided. The material of the structure is usually stainless steel, but other materials may be used like the oil tank.

The volume of the oil tank and the amount of oil used for cooking are not limited, but an oil amount of 18 to 50 liters is preferable if the present invention is applied to a self-supporting fryer, and is 0. 5 to 10 liters is preferable, and 1 to 2 liters is preferable for home use.
A fryer that continuously cooks foods to be cooked in a high-temperature oil tank using a belt, chain, roller, or gear, or by moving foods in oil by a partition plate or the like. In this case, a single oil tank may be fixed with a plurality of structures, or may be moved over a plurality of oil tanks in a cooking process. In all the fryer, one structure may have a plurality of oil tanks and low-temperature regions, and the lower part of one oil tank may branch into a plurality of low-temperature regions. It may be a low temperature region.

As the heating method of the heater, a heating wire type housed in a metal tube such as stainless steel is suitable because of its high degree of freedom in shape, but it is also possible to use a gas combustion tube type or IH type, and is not limited. .
The amount of heat generated by the heater is mainly determined by the relationship between the amount of oil and the area of the high-temperature oil tank. If a general fryer, a three-phase power source of 200 V or higher is preferably used, and if it is a desktop fryer, preferably 200 V or higher. The power consumption is preferably the amount of oil in the high-temperature oil tank (unit: liters) × 0.4 to 0.5 kW, and the power consumption per surface area of the heater heating part is 2.5 It is preferable to set it to -3W / cm < ² >.
If the power consumption per surface area of the heating area of the heater is higher than this, the heater is likely to overheat, the oil deteriorates due to contact with the overheated heater, and in some cases, oil smoke is generated. As a result, it becomes difficult for the fried residue to pass.

  The depth of oil in the high-temperature oil tank for cooking is preferably 60 to 80 mm for a self-supporting fryer for mass cooking, preferably 30 to 70 mm for desktop use, and preferably 30 to 50 mm for home use. The reason for this is that if it is deeper than this, the ratio of vaporization without reaching the low temperature oil tank increases, and if it is shallower than this, when the cooking object is thrown in, the cooking object will hit the fryer structure and be damaged. This is not preferable because the object to be cooked is too close to the heater and may cause partial carbonization.

The bottom of the oil tank, which is a part of the low-temperature oil tank, is provided with an inclination of 1 to 70 degrees, preferably 25 to 45 degrees so that the fried residue and moisture slide down and accumulate in the low temperature region. A steep slope is more suitable for integration, but if it is too steep, it becomes difficult to arrange the components due to the height restriction of the product.
The volume of the low temperature oil tank is preferably 40 to 80% of the volume of the oil in the upper high temperature oil tank from the heater, and if it is less than this, the temperature of the low temperature oil tank tends to rise. This is not preferable because the properties are impaired.

The low-temperature region is a part of the low-temperature oil tank and includes the deepest part, and the horizontal cross-sectional area at the top is at least 50%, preferably 80% or more with respect to the horizontal cross-sectional area at the bottom of the high-temperature oil tank. The distance to the top of the low temperature region is preferably 25 to 60 mm for a self-standing type, 15 to 50 mm for a desktop type, and 15 to 40 mm for home use. The reason for this is that if it is narrower than the above, or if the distance is long, most of the water falling from the high-temperature oil tank will be vaporized in the temperature range of 80 ° C. or higher, and the probability that the lifted residue will repeat floating due to convection increases. , Therefore not suitable for precipitation. On the other hand, if it is too close, a large cooling capacity is required and energy efficiency is lowered, which is not preferable.
In addition, the volume should be 25 to 75%, preferably 40 to 60% with respect to the volume of the low temperature oil tank. The reason for this is that the temperature in the low temperature region easily rises if the volume is less than this. If it becomes unstable and more than this, the amount of oil increases or strong cooling is required, which is not preferable because economic efficiency is lowered.

In addition, the shape of the low temperature region may be constituted only by the oil tank wall surface and the bottom slope, or only the bottom slope, but the method of forming a depression further from the bottom slope and making the low temperature region including the depression shape has fluidity. Since it reduces, it is suitable for fried residue and moisture precipitation and storage.
Furthermore, a structure in which the horizontal cross-sectional area at the upper part of the low temperature region is wide, the intermediate part at the lower part thereof is narrow, and the structure at the lower part is wide again is more suitable for storage because it has lower fluidity and is isolated from the heat source. On the other hand, the method of using the depression or one part thereof as a low-temperature oil tank is not preferable because it is difficult to satisfy the previously raised conditions such as the top area.
It should be noted that the lower part of the oil tank including the depression is preferably processed so that the corner has an aspect so as to be suitable for discharging and cleaning, and the shape is preferably a shape having a small angle such as a cylindrical shape or a conical shape.

  Next, a method for providing a cooling tank and / or a cooling pipe to cool the low-temperature oil tank will be described. The purpose is to keep the lower part of the low-temperature oil tank fried by cooling so that dregs and moisture are likely to precipitate, and moisture is not easily vaporized. For this purpose, it is necessary to keep the temperature in the low temperature region at 80 ° C. or lower. Specifically, it is effective to provide a heat medium tank covering all or the main part of the low temperature oil tank. The case where oil or the like can be used and water is used as the heat medium will be described below.

Cover the low-temperature oil tank with a water tank, and inject the water into the tank with water injection pipe for injecting cold water such as tap water, water injection switchgear, and water at the top of the water tank to inject air at the top of the water tank. It is effective to provide an overflow drain pipe for discharging. At this time, the volume of the water tank is preferably 100 to 200% with respect to the oil amount, but if it is less than that, the required cooling power is ensured by continuing the water injection.
Since water absorbs a lot of energy when the temperature rises, the water stored in the aquarium absorbs the amount of heat to prevent a rise in the temperature of the low-temperature oil tank for relatively small amounts of cooking, and continuously cooks in large quantities. If the water temperature rises due to, for example, tap water, the temperature of the water tank is lowered by injecting cold water such as tap water from the water injection pipe by operating the switchgear, and if necessary, water injection is continued and / or By increasing the amount of water injected per unit time, the oil in the low temperature oil tank can be kept at a low fluidity temperature suitable for precipitation.
The temperature of cold water such as tap water is preferably 15 to 25 ° C., and the reason is that if it is less than this, condensation tends to occur, and if it is more than this, the cooling power is reduced. Moreover, soft water is preferable in order to prevent clogging of piping and the like.

Also, if you wait while maintaining the temperature of the hot oil tank after cooking, or if you are cooking sporadically, the temperature of the water tank gradually decreases due to heat dissipation inside and outside the casing without water injection In addition, there is no need to use cooling water wastefully. In addition, it is efficient because it is discharged preferentially from the uppermost water that has become hot when water is injected, and it does not require constant water injection due to the heat energy absorption capacity of the aquarium. Enables cost cooking operations.
Furthermore, the overflow discharge pipe is located at the uppermost part of the water tank, and has an effect of being quickly discharged even when bubbles are included in the injected cold water or when bubbles are generated by evaporation of moisture. In addition to the above water tank structure, a method of cooling with running water by passing a cooling pipe inside or outside the low temperature oil tank is also effective, and a method of combining these with the water tank structure is also effective.

In addition, a cooling pipe made of a heat medium is circulated between the outer periphery of the housing, and an ascending force caused by buoyancy generated by heating in a low-temperature oil tank and a descending force generated by increasing the specific gravity due to air cooling are used. In addition, a method of circulating the water, a method of forcibly circulating with a pump or a screw, and a method of cooling using a refrigeration cycle are also effective. In the refrigeration cycle, a vapor compression type using ammonia, hydrocarbons, carbon dioxide or the like is preferable, but other types such as an air refrigeration type, a vapor injection type, an absorption type, an adsorption refrigeration type, etc. may be used.
In any of the above methods, heat is taken from the low oil tank and the heat is transferred to the outside. The cooling method employed in each product configuration is the temperature in the low temperature region of the low temperature oil tank. Has a cooling ability to keep the temperature at 80 ° C. or lower, preferably 70 ° C. or lower. However, although an excessively low temperature is suitable for precipitation, it is not preferable because it requires a larger cooling capacity and may impair the economy.
As a method for managing these temperatures, a method of providing a temperature sensor at the top of the low temperature region is preferable, but in addition to this, a method of providing a temperature sensor at another point in the low temperature oil tank or a cooling tank is also possible. In this case, it is necessary to perform temperature management after sufficiently grasping the correlation between the oil temperature or water temperature at the sensor position to be provided and the temperature at the top of the low temperature region.

  Next, the effect by the 1st structure of this invention is demonstrated. If cooking is performed by heating the oil in the high-temperature oil tank, the temperature of the oil in the low-temperature oil tank gradually increased to the same level as the room temperature, but in the configuration according to the present invention, the low-temperature oil tank has a cooling tank and / or a cooling pipe. Thus, the temperature of the oil in the low temperature region of the low temperature oil tank can be kept at 80 ° C., preferably 70 ° C. or less, and the low temperature region is kept in a low fluidity state suitable for precipitation. As a result, the deep-fried dregs that have fallen from the top and have reached low-fluidity oil further fall, and slide down and accumulate on the inclined portion. The fried residue is stored in the low temperature region at a low temperature until it is subsequently discharged or until cooking is finished.

Also in the configuration according to the present invention, water having a small mass is vaporized, but moisture having a larger mass falls due to a difference in specific gravity while moving violently due to convection, etc. Passing through, dropping to a low temperature region of 80 ° C or lower where the fluidity is low, precipitating, being stored at a low temperature until discharged, or finishing cooking, and discharged together with low temperature oil and fried residue Is possible.
As a result, the fried residue does not progress in carbonization and the accompanying oil deterioration, floats in the high temperature oil tank and does not adhere to food, oil splashes, water vapor and oil mist decrease, and the environment in the kitchen is reduced. Improve, reduce the burden of cleaning, reduce the dirt in the housing, the oil does not deteriorate in the low temperature region of the low temperature oil tank, the high temperature oil is water or vaporized in the high temperature oil tank By reducing the chance of contact with moisture, the deterioration of the oil is suppressed, and the effect of improving the flavor of the deep-fried food is produced. The operation is safe and the fried residue does not spontaneously ignite or emit smoke.

A second configuration having a pipe and / or a valve or a plug according to the present invention will be described below. First, a structure in which a plug is provided and a configuration in which a pipe and a plug are provided will be described.
The stopper used here is a lid that rotates and opens or closes, or is crimped and released by a spring, and is mostly made of stainless steel, and heat-resistant rubber such as fluorinated rubber or expanded graphite or other sealing materials to prevent leakage O-rings or seats are provided.
If it is a method using a stopper, it is possible to provide a discharge port directly in the low temperature region of the low temperature oil tank, and if a discharge port that is difficult to clog is required, the maximum size can be close to the area of the bottom of the low temperature region. Yes, it can be provided even when there is no space.

  The outlet for the plug may be provided directly downward, but it may be provided after being guided to a direction and point where it is easy to work with piping. There is a case where a stopper is provided so as to discharge in a direction close to. As an example of this, a pipe having an inner diameter of 15 to 60 mm is provided downward in the deepest part of the low temperature region, immediately curved in a range of 70 to 89 degrees, and provided with a stopper that opens and closes by rotation. It is a shape to use as. In addition, if it is a stopper which crimps | compresses and releases | releases with a spring, it does not need to be circular, and it is also possible to make a pipe | tube flat or square. However, with the stopper method, once it is released, it is difficult to stop it during discharging.

Next, a method for providing piping and valves will be described. In cooking, in which a large amount of fried residue and moisture are continuously generated mainly due to business use, if left untreated, it overflows from the low temperature region and approaches the heater, so it is necessary to remove this during cooking.
Specifically, the most common method is to provide a discharge pipe that also serves as the main drain at the deepest part of the low temperature region. Apart from the main drain, the frying waste and oil containing moisture are directed upward. A configuration in which a discharge pipe is provided so as to suck is also effective. These discharge pipes have valves that can be opened and closed at any time, and the valves may be manually operated or electrically operated.

Finally, a method using piping will be described. Separately from the main drain, a discharge pipe is provided in the low temperature region, and a screw pump that rotates and conveys a screw with spiral teeth, a gear pump that conveys with two rotating gears, a tube pump, etc. A method of providing a pump capable of transporting a fluid having a low fluidity and a fried residue which is a solid substance, and performing the suction and discharge is preferable because the position of the discharge destination, particularly the height, can be freely selected. Further, this method is preferable in that it is easy to adjust the discharge speed and the discharge amount, and therefore, it is possible to continuously discharge, and the variation of the cooking surface accompanying the discharge can be reduced. A siphon method is also effective. Furthermore, such pumps suck the fried residue and moisture-containing oil, or suck and push up and discharge at a position higher than the cooking surface, remove the fried residue while dropping by gravity, separate the moisture, and then The method of returning the oil to the oil tank is effective.
It is also effective to automate the discharge by using timer information and sensor information after making the valve and / or pump electric. Similarly, the cooling is executed and stopped and / or the intensity is adjusted based on the temperature sensor information. It is also effective to automate the temperature control of the low temperature oil tank.

The effect by a 2nd structure is demonstrated. As described above, according to the method of providing a plug or a pipe and a plug, it is premised that the oil is cooled after the cooking is finished and then discharged, but the stored fried residue and moisture can be recovered to the outside. It is possible, the work is safe, and the collected fried residue does not ignite spontaneously on contact with air.
Also, using a method with pipes and valves, or pipes, if cooking is performed continuously or intermittently so that fluctuations in the cooking surface due to the discharge are reduced, cooking will not be interrupted, and fried residue and moisture will be removed. It can be recovered outside at a low temperature, the operation is safe, and the fried residue recovered at a low temperature does not spontaneously ignite.

Hereafter, the structure which has the space | gap which is the 3rd structure by this invention is demonstrated. The shape of this structure covers the horizontal cross section of the oil tank, provides a gap for expansion between the oil tank wall surfaces on all sides, and has a plate-like structure of 0.3 to 10 mm with many holes. , One with a dish-like slope at the top of the hole, one with a slit instead of a hole, a method in which isosceles triangular prisms are arranged horizontally with an apex on the isosceles as a ridgeline, and a similar mountain There are a method of forming a mold with an inclined shape with a plate, and a grid-like adjacent grid having a gap every other square, and a non-void portion having a pyramid-like inclined structure.
As for the size of the gap, a circle of 2 to 20 mm and a slit of 1 to 20 mm are often used. However, in cooking using breadcrumbs of a general size, a circle of 8 to 10 mm or a slit of 5 to 8 mm is preferable and is not a gap. The portion is preferably inclined toward the gap.
Further, the opening ratio of the flow path area with respect to the horizontal cross-sectional area is 20 to 80%, preferably 40 to 60%. It becomes difficult to pass. The material used for the structure may be a stainless plate having a thickness of 0.3 to 2 mm, but a material having a low thermal conductivity such as a fluorine resin or ceramic having a thickness of 1 to 10 mm is preferable.

According to the third configuration in which the structure having the voids is provided, the fried residue and moisture fall in the oil due to the difference in specific gravity, pass through the voids of the structure, and further fall and settle in the low temperature region. On the other hand, this structure is an obstacle to rocking when a large amount of ingredients are added or when a cooking worker stirs, and to the intense up and down flows that are noticeable when ingredients with a lot of moisture are added. Since it works and is suppressed, the temperature of the oil below it is difficult to rise, and the required cooling capacity is low.
The structure and the heater are installed at a distance of 3 to 60 mm, preferably 5 to 30 mm. This ensures convection fluidity, and the oil in the high-temperature oil tank is easy to be heated. Overheating of the heater due to shortage, temperature rise of the structure due to radiant heat, and temperature rise in the low temperature oil tank are avoided, and the effect of promoting the fryer effect of the first or second configuration according to the present invention is brought about.

Below, the other structure which promotes an effect by using together with this invention is demonstrated.
In the fryer according to the configuration of the present invention, the low-temperature oil tank is kept at a low temperature by the cooling tank and / or the cooling pipe, and therefore it is not necessary to perform cooling by the chimney effect unlike the general fryer. For this reason, it becomes possible to block the space in the casing at the upper part of the low temperature oil tank, and as a result, the suction of the air in the kitchen due to the chimney effect using the high heat at the top of the casing is eliminated, and the interior of the casing due to oil smoke or oil mist etc. Dirt is drastically reduced, facilitating daily cleaning work, reducing the amount of exhaust heat released into the kitchen, thus improving the thermal efficiency of the fryer and reducing the amount of energy required for air conditioning of the kitchen and the like.
In addition, if the blocked upper space is filled with a heat-resistant heat insulating material, or part or all of the space is made into a vacuum structure, or if each surface in contact with the space is covered with a heat-resistant heat insulating material, the above effect is further enhanced, The radiant heat that the person receives from the flyer is also greatly reduced.

Moreover, in the structure which covered the said low-temperature oil tank with the water tank, the structure which interrupts | blocks the space inside a housing | casing with a water tank including the position of a low-temperature oil tank upper part is effective. As a result, a structure in which the outer peripheral surface of the water tank is exposed to the outside of the housing is possible, resulting in an expansion of the water tank volume, and a structure that is air-cooled from the outer peripheral surface, thereby reducing the opportunity for water injection, It becomes possible to improve the degree of freedom in the lower part of the housing by flattening the water tank.
In addition, it is conspicuous in a fryer that is heated by a large amount of power, but the relay and control board for controlling the power supply generate high heat, so if the water tank also has these cooling functions, the cooling capacity is high and the additional cost is increased. And the dirt does not accumulate near these parts as in the case of air cooling.

A fixed or detachable oil supply hopper is provided at a position higher than the cooking oil level, and this hopper and a low-temperature oil tank are connected by an oil supply pipe. In the fixed type, the oil supply hopper and the oil supply pipe are supplied. It is also effective to cover the tube with a heat-resistant heat insulating material and to be made of a material having low thermal conductivity such as a resin.
As a result, oil that has been removed from frying waste and moisture from the oil discharged from the fryer according to the present invention, or oil that is separately added to compensate for the decrease due to cooking, may be supplied during cooking via the oil supply hopper. The oil temperature of the low-temperature oil tank is not increased, the oil temperature of the high-temperature oil tank is not lowered, and unnecessary reheating is not required, which brings about an effect of improving energy efficiency.
Also, if oil is supplied via the oil supply hopper, even if the supplied oil contains moisture, it will not come into direct contact with the hot oil, and the moisture will reach the low temperature oil tank and fall without being heated. Because it precipitates, it does not cause oil splashing or oil degradation. For this reason, even in continuous cooking over a long period of time, cooking with less deteriorated oil can be continued by promoting the effects of the present invention, and if the supplied oil is put into the oil supply hopper and discharged immediately thereafter, it will depend on the discharge. It also has the effect of suppressing cooking surface fluctuations.
In addition to this, when the inclination angle of the bottom of the low-temperature oil tank including the low-temperature region is small, a method of providing a vibration motor is also effective in order to promote the slipping of the frying residue and moisture.

If the volume of the low temperature region is larger than the assumed amount of frying residue and moisture generated, it is not necessary to discharge the fried residue until the end of cooking, and a configuration without an outlet in the low temperature region is possible. Suitable for fryer with a volume of 10 liters or less, preferably 5 liters or less.
Specifically, a storage part that is a part of the low temperature region is provided on the inclined surface of the low temperature oil tank, the storage part is swelled in the lower part from the upper part, the bulge is biased only in one direction, and the direction with the bulge The upper part of the oil tank on the opposite side is provided with a spout so that the oil tank is inclined and oil can be poured outside.
After cooking is complete and the oil has cooled, fry by slowly lifting the end of the oil tank opposite to the bulging direction up to 90 degrees with the fried residue and moisture sufficiently settled in the reservoir. Oil from which scum and moisture have been removed can be poured out of the oil tank and taken out.
Since the fried residue, moisture and oil remain in the reservoir, this time, if it is slowly tilted in the opposite direction, it can be taken out to an external container. At this time, it passes through a stainless steel mesh and / or filter paper or paper towel, etc. If the fried residue is removed, water and oil are gradually separated in the container, and oil suitable for reuse can be recovered.

The following is a description of the fried cooking method according to the present invention.
In general, most fried cooking is performed in the range of 165 to 190 ° C, but in cooking over a long period of time at low temperature, the temperature may be as low as 100 ° C. Then, although it is a short time, cooking may be performed at a temperature exceeding 200 ° C. When fried cooking is performed at 100 to 210 ° C. including these, if the heating is performed from the bottom, the moisture does not escape and the whole amount is vaporized, and the carbonization of the fried residue without escape is also promoted. In addition, in cooking using a general fryer, the temperature of the low temperature oil tank is low at the beginning of cooking, and fried residue and moisture can be precipitated, but the oil temperature in the low temperature oil tank also increases when cooking a large amount of time or cooking for a long time. As a result, most of the moisture is vaporized and carbonization of the fried residue proceeds, and the carbonized fried residue may adhere to the food.

  On the other hand, in the fried cooking method according to the present invention, the oil temperature in the low temperature region at least below the heater and in the low temperature oil tank is kept at 80 ° C. or lower. Carbonization of the metal hardly progresses. If the temperature is higher than this, the fluidity becomes high and precipitation is difficult, and the possibility of moisture vaporization increases. If the temperature is 100 ° C. or higher, the moisture is surely vaporized. Although the oil temperature in the low temperature region is 80 ° C. or lower, this means that the uppermost temperature in the low temperature region is 80 ° C. or lower. The oil has a high temperature at the top and low at the bottom. The temperature is low. The oil temperature in the low temperature region set at 80 ° C. or lower is preferably 70 ° C. or lower, so that the fried residue and moisture are more likely to settle, and carbonization does not proceed easily even after storage for a long time, and bubbles due to vaporization are also generated. Further decrease.

In cooking that generates a lot of fried debris, it is equivalent to the amount reduced by discharge without interrupting cooking due to fluctuations in the cooking surface by intermittently discharging the precipitated fried debris and moisture with oil during cooking. If oil is supplied to the oil tank, cooking can be continued. At this time, the fluctuation range due to the discharge is preferably 20 mm or less, more preferably 10 mm or less, and the discharge amount allowed at one time is obtained by multiplying the horizontal sectional area of the oil tank by the above-described fluctuation range.
In the case of discharging using a pump, etc., discharging may be performed continuously with a reduced discharge amount per time.
On the other hand, in cooking where the amount of fried residue and moisture generated is small, the amount of discharge per hour in discharge is reduced or the interval between discharges is increased, but during cooking, the fried residue and moisture are not discharged and the temperature is low. It is also possible to perform a discharge or removal operation after confirming that the temperature of the high-temperature oil tank has also decreased after the cooking is completed.

  As a result, the carbonized fried residue does not adhere to the food and impair the flavor, the carbonized fried residue does not impede the fluidity during discharge, and the recovery of the fried residue is performed at a low temperature. Safe, recovered fried residue does not ignite spontaneously when exposed to air, and part of the water is recovered to the outside, so the amount of oil splashes, water vapor, oil mist and waste heat is reduced, and the environment in the kitchen Will reduce the burden of cleaning, and the inside of the housing will be less likely to get dirty, so there will be fewer failures, and the chance of high-temperature oil coming into contact with moisture will be reduced and oil deterioration will be suppressed, improving the flavor. The number of times or period of use of the oil increases and the oil consumption can be reduced.

  According to the present invention, the deterioration of the oil is suppressed, the flavor of the deep-fried food is improved, the oil replacement frequency is lowered, and the environment in the kitchen is improved by reducing oil splashes, water vapor, oil mist and oil smoke, and exhaust heat. Thus, the burden of cleaning is reduced, the spontaneous combustion of the fried residue is prevented, and the work associated with cooking is safe.

Hereinafter, an embodiment in which a water tank is used for cooling a low-temperature oil tank will be described. The embodiments are examples for understanding the gist of the invention, and do not limit the content of the invention unless otherwise specified. As shown in FIGS. 1 to 6, an oil tank 2 for storing cooking oil for cooking is fixed in the casing 1, and an electric heater 2 c of 10 kW is arranged in the middle part of the oil tank 2, and the upper part from there A high-temperature oil tank 2b for cooking and a lower oil tank 2g below it are 30 liters of oil used for cooking, and the height of the casing 1 is 800 mm. The power density per surface area of the heater heating part is 3.0 W / cm ² and the cooking area of the oil tank 2 is 2000 cm ² .

  The oil tank bottom 2h forming the low-temperature oil tank 2g has an inclination of 30 degrees so that the frying residue and moisture slide down, and the low temperature area from the low temperature area sensor 2r provided on the oil tank bottom 2h to the lower cylindrical accumulation part 2i. It is said. The bottom of the stacking portion 2i is inclined toward the discharge port 2j, and the discharge pipe 2n is provided with an on-off valve 2k and an operation rod 21 for operating the valve from the front. A warning sound is emitted to prompt the discharge, but the time interval can be changed depending on the cooking contents, and since there is cooking where there is little cooking amount or fried residue does not occur, it is possible to select not to emit a warning sound. Further, a convection preventing portion 2e is provided 15 mm below the lower end of the heater 2c in the low temperature oil tank 2g, and a space between the heater 2c and the convection preventing portion 2e is a heater lower convection region 2d.

The entire low temperature oil tank 2g from the convection prevention part 2e is surrounded by the water tank 3, and the volume of the water tank 3 is 45 liters. The water injection pipe 3a for injecting tap water C is inserted into the water tank 3 from the height near the oil tank bottom 2h. The water injection opening / closing device 3e having a variable flow rate is provided, and is connected to the water supply in the kitchen by a pressure-resistant desorption hose.
The space inside the housing 1 is divided into upper and lower parts by a partition plate 1a in the housing at the same height as the aquarium ceiling surface, and a heat-resistant heat insulating material 1b is applied to each surface in contact with the upper housing space 1c. Moreover, the overflow discharge pipe 3b is installed upward from the uppermost end of the water tank 3, and is then bent and dropped toward the lower part. The tip of the overflow discharge pipe 3b joins with the water tank drain pipe 3c and then becomes a drain hose. Connect and lead to drainage. A water tank drain pipe 3c used for draining the water tank 3 is provided at the lowermost end near the front surface of the water tank 3, and is connected to the overflow discharge pipe 3b at the lower part.

As shown in FIG. 3, the heating wire heater 2c has a structure in which the central portion of the oil tank 2 is opened wide as viewed from above, and the heater mounting portion 2o is parallel to the main body of the heater 2c and has a heat resistance on the front side of the high temperature oil tank 2b. It is a fixed type attached via a sealing material.
The convection prevention part 2e is a 4mm thick heat-resistant fluororesin plate with a large number of holes 9mm in diameter, with an aperture ratio of 50%, divided into four parts, and is inserted into the lower part from the opening in the center of the heater 2c. Similarly, the entire oil tank 2 is installed so as to be divided horizontally by the convection prevention portion support structure 2f inserted from the opening.
In the upper part of the heater 2c, a food fall prevention net 2p is provided so that the food does not directly touch the heater 2c during cooking and does not fall below this.
The solid state relay 5b for power supply and the electromagnetic switching device 5c are installed on the front side with the water tank 3 as the back so that the water tank 3 becomes a cooling device, and then housed in the power supply box 5a. The control board 5f including the timer function and the warning sound generator 2q are housed in the display / control box 5d, and the entrances and exits of the cables are sealed so that water and oil do not enter the interior, and air flow is as much as possible. It is shut off.
When the low temperature region sensor 2r detects a temperature of a certain value or more, the warning sound generator 2q emits a warning sound different from the warning sound that prompts the discharge to prompt water injection, but the constant value is 60 ° C to 80 ° C. The initial value is 70 ° C. The high temperature oil tank 2b is provided with a temperature sensor 2m for adjusting the cooking temperature.

The purification unit 4 includes a deep-fried residue separating unit 4a, a fine solid matter filter 4b, and three sedimentation tanks. The deep-fried residue separating unit 4a that removes the deep-fried residue from the oil mixed with the deep-fried residue and water is made of stainless steel. The fine solid matter filter 4b, which is made of a stainless steel container for preventing the mesh and oil from overflowing to the outside, is provided on the upper portion of the first settling tank 4c so as to remove fine solid components with filter paper.
The first settling tank 4c, the second settling tank 4d, and the third settling tank 4e are partitioned but have an integral structure, and a hole 4h through which oil and moisture pass through the partition between the first settling tank and the second settling tank. However, the partition between the second sedimentation tank and the third sedimentation tank is provided with a slit 4j in the vertical direction, and from the first sedimentation tank 4c where the oil first falls toward the second sedimentation tank 4d, There is also an inclination from the three precipitation tanks 4e toward the second precipitation tank 4d, and the second precipitation tank 4d is provided with a precipitation water drain pipe 4f equipped with an opening / closing device for discharging the precipitated water. In addition, the oil whose water separation has progressed is pumped out from the third settling tank 4e by a shear, but the bottom of the first settling tank 4c is placed in the third settling tank 4e so that the operation can be facilitated even when the amount of oil is small. I have a head against it.
Moreover, since it is necessary to drop the whole amount of oil at the time of cleaning, the total volume of the three sedimentation tanks is 40 liters which enables this, and is equipped with a purification unit wheel 4g. An oil supply hopper 6a is provided at the front upper part of the oil tank 2, and the height position of the bottom slope of the bottom slope is in the same vicinity as the cooking oil surface 2a, and the oil tank bottom 2h is connected via a flat oil supply pipe 6c. The oil supply hopper 6a and the oil supply pipe 6c are covered with a heat-resistant heat insulating material 1b connected to the low temperature oil tank 2g along the slope.

Using the fryer configured as described above, cooking was performed according to the fried cooking method of the present invention. The conditions before starting cooking are as follows.
1) The room temperature of the kitchen and the water temperature in the water tank 3 22 ° C
2) Temperature setting of the low temperature region sensor 2r that emits a warning sound that prompts water injection 70 ° C
3) Temperature of tap water to be poured 19 ℃
4) The amount of water to be poured once and the time required for this 10 liters / 60 seconds 5) The temperature of the cooking temperature sensor before heating 23 ° C.
6) Cooking set temperature 180 ℃
7) Discharge amount and discharge interval 1 time 2 liters every 10 minutes 8) The purification unit 4 was charged with 4 liters of oil before cooking was started.

The following four types of cooking objects were made in one cooking, and cooking was performed 9 times each, with a total of 36 times for 3 hours while changing the type at intervals of 5 minutes.
1) Frozen croquettes 80g x 20 pieces 2) Frozen potato fries 1.5Kg
3) Frozen fish fried 120g x 15 4) Frozen chicken fried 1.5Kg

The cooking process and results were as follows.
1) Heating is started, and after reaching 180 ° C., the first cooking is started. Immediately after the third cooking is started, 2 liters of oil is introduced from the third settling tank 4e into the oil supply hopper 6a, and then 1 When the second discharge was performed, the cooking oil level first increased by 2 mm, and then decreased by 8 mm due to the discharge. After that, the cooking oil level gradually increased and recovered to the original cooking oil level after 20 seconds from the discharge. In this discharge, a small amount of fried residue was found in the fried residue separation part 4a.
2) Similarly, immediately after starting the fifth cooking, 2 liters of oil from the third settling tank 4e was put into the oil supply hopper 6a, discharged for the second time, and discharged for the third and subsequent times in the same manner.
3) By the end of the final 36th cooking, a total of 3 liters of new oil was added to the oil supply hopper 6a in 6 batches to compensate for the decrease due to cooking.
4) Although heating was stopped after cooking was completed, oil supply and discharge were repeated every 10 minutes in the same manner, and four discharges were performed after cooking was completed.
5) During this period, an alarm sound for prompting the first water injection was issued in 127 minutes from the start of the first cooking, so water was injected, and thereafter water was injected in the same manner at 151 minutes and 176 minutes. In addition, heating was stopped after cooking, but after that, oiling and discharging were repeated every 10 minutes in the same manner, and discharging was performed four times after cooking.
6) During this period, the amount of deep-fried debris included in the second and third discharges gradually increases and becomes almost the same level after the fourth, including those recovered after cooking. The volume of the fried residue is 1.5 liters and the temperature is 36 ° C. after being left in 4a for 30 minutes, and the amount recovered by the fine solid filter 4b is 60 milliliters. The amount of water recovered from the water drain pipe 4f was 180 ml. In addition, the recovered fried residue was not carbonized, and the whole was a slightly ocher cream color with a small amount of brown fried residue. At the same time, fried residue and precipitated water were hardly observed in the oil tank.
7) Immediately after the final round of cooking, the temperature of the oil in the high-temperature oil tank was 180 ° C. When the temperature of each part of the outer periphery of the case was measured with an infrared radiation type thermometer, it was 35 ° C. at a point 300 mm from the floor on the left and right sides, 44 ° C. at a point 750 mm, and 50 ° C. at the ceiling of the case. There were no spots above 50 ° C on the side.

What can be said from the above results is that if cooking is performed by the fried cooking method according to the present invention using the embodiment according to the present invention, it is possible to safely recover the fried residue and moisture during cooking. The fluidity at the time of discharge is maintained by not carbonizing, the fluctuation of the cooking surface due to discharge is small, cooking can be continued, and the fried residue is not carbonized and spontaneously ignited by being recovered at low temperature However, the amount of water vapor is reduced because water can be recovered as water.
Furthermore, in the case of a general fryer, the upper part of the casing is hot enough to cause burns when touched, and the cooking operator feels strong radiant heat from the fryer. However, in the fryer and fried cooking method according to the present invention, the casing temperature is kept low. Therefore, there is almost no risk of burns due to touching the casing and no deterioration of the work environment due to radiant heat.

Next, the performance of suppressing the deterioration of the oil was compared with a heating wire type self-supporting general fryer. The specifications of the general flyer to be compared are as follows.
1) Oil volume: 34 liters 2) Heater power consumption: 10kW
3) Power density per heater surface area: 3 W / cm ²
4) Oil tank area: 2000 cm ²
The general fryer to be compared is self-supporting, power consumption, power density per heater surface area, and oil tank area are the same, but the amount of oil is 34 liters. In the embodiment of the present invention, the amount of oil is 30 liters. However, two liters of oil amount to be added at the time of discharging are started by adding 4 liters to the purification unit 4 in advance, and the comparison conditions are satisfied.

In the experiment, the above 36 times of cooking is considered as one step, one step in the morning, one step in the afternoon with a break of 1 hour, and a total of four steps in two days. During this period, in the embodiment of the present invention, the above experiment is performed. In the same manner as described above, water was discharged once every 10 minutes, water was poured in accordance with a warning sound, and filtration was performed with a filter at the end of the first and second days in a general fryer. Measure the TPM value, which is the ratio of polar compounds that increase due to deterioration before and after the start of each process over two days. In addition, the measurement after the end of the afternoon was performed 30 minutes after the end of the filtering operation by the filter of a general fryer. At this time, the fried residue was carbonized, and oil smoke was also generated when dropped with oil on the filter. Admitted. In the examples of the present invention, neither carbonization of fried residue nor generation of oily smoke was observed.
Table 1 shows the measurement results of the TPM value. From this result, cooking by the first embodiment of the present invention and the fried cooking method is superior in the effect of suppressing the deterioration of oil, and the frequency of oil change can be reduced. I can say that.

In addition, although the oil reduced by cooking was added by the end of the last cooking, the total amount was 12 liters in this embodiment, and 13.5 liters in a general fryer. This difference was presumed to be due to the disappearance of oil splashes and oil mist, and the difference in the lack of oil in the deep-fried food.
Moreover, the taste comparison test was done about four types of cooking results performed from the beginning of the afternoon of the 2nd day of the said experiment. The experimental method is to answer by A or B which of the same kind of deep-fried food on AB two dishes is felt, and there are 12 subjects.
As a result, the number and ratio of delicious foods according to this embodiment are as follows.
1) Frozen croquettes 9 people 75%
2) Frozen potato fries 10 people 83.3%
3) Frozen fish fried 8 people 66.7%
4) Frozen chicken 9 people 75%
During cooking, the temperature was measured 100 mm behind the back of the housings of both the fryer and 300 mm above the top, and it was 56 ° C. for the general fryer and 45 ° C. in the present embodiment. Similarly, a significant difference was confirmed.
In addition, after the completion of cooking for two days, the state of the surroundings of both fryer separated by about 10 m was confirmed. In the general fryer, the trace of the oil splash was seen in a wide range up to the casing and the surrounding floor, but in this embodiment, the trace was clearly small and the range was also narrow. In addition to the traces of oil splashes, the general fryer is oily as a slimy oil on a wide range of surrounding floors and walls. This is due to the effect of oil mist, and the extent of this embodiment is clearly light. There was a similar difference in oil stains inside the body, and the time required for cleaning was half that of a general flyer.

  The following experiment was conducted separately from the above experiment. The contents of the experiment are to prepare 200 ml of tap water in a cup and throw it into the cooking oil surface of a high-temperature oil tank at 180 ° C. at once, and throw in 10 pieces of 25 ml of ice blocks separately. This experiment assumes an accident that occurs in a kitchen that uses a lot of water and ice, and if it is a small scale, it is something that everyone has experienced, and the result is almost an explosion. Is too dangerous to implement. On the other hand, when this was done with the flyer according to the present embodiment, small bubbles were generated in tap water and oil splashes such as pachi, pachi, pachi were generated several times immediately, but in the ice block that was continuously charged, There was a tiny noise, but no oil splashed. The reason for this result is that water is heated by oil, but it takes time to rise in temperature, so it reaches the low temperature region before reaching 100 ° C. This condition is more advantageous for ice blocks. Because there is.

In the following, an embodiment for a small desktop that does not have a discharge port in a low temperature region will be described. As shown in FIG. 7, it is composed of a stainless steel casing / water tank 11, an oil tank 12 detachable upward, a heating wire heater 13 with a power consumption of 1 kW, and a control box 14 made of resin. use. In addition, a temperature setting dial 14a is provided at the top of the control box, and a vibration motor 14c is provided inside, and the heater 13 is fixed.
The upper part of the oil tank 12 from the heater 13 is inclined toward the high temperature oil tank 12a, the lower part is a low temperature oil tank 12b, and the lower part is inclined toward the storage part 12c which is a part of the low temperature region. The storage part 12c has a shape in which the lower part swells in one direction, the bottom part inclines in the swelled direction, the ceiling inclines toward the upper part so that bubbles can escape, and the swelled side of the storage part 12c A spout 12d to the outside is provided in the upper part of the oil tank 12 on the side to be used, and the amount of oil is 3 liters.

The lower part of the low-temperature oil tank 12b from the position where the wall surface and the bottom slope intersect is the low-temperature region including the reservoir 12c. Therefore, the horizontal cross-sectional area at the top of the low-temperature region is the same as the area of the bottom of the oil tank. The water temperature confirmation label 11g having a function is provided at a horizontal position with the top of the low temperature region. In addition, a water inlet 11a at the bottom of the casing / water tank 11, a water outlet 11b at the time of discharge of water whose temperature has risen due to pouring at the lower end of the heater 13 and a horizontal position, and a cooking oil level 12f at a horizontal position. An end drain port 11c that drains water when cooling including the high-temperature oil tank after cooking is completed, and the end drain port 11c is normally closed by a water level adjusting plug 11d for selecting the drain port.
In addition, a confirmation window 11e made of transparent heat-resistant glass is provided on the upper portion of the storage portion 12c and on the opposite surface thereof, and on both sides of the casing / water tank 11, so that it can be seen to the other side of the fryer, The amount can be confirmed.
The volume of the water in the enclosure / water tank 11 is 2.7 liters up to the drain outlet 11b during cooking and 3.4 liters up to the drain outlet 11c at the end, and the control box support structure for attaching and detaching the control box to the casing / water tank 11 11f is fixed.

When cooking, oil is filled up to the cooking oil level 12f, tap water C is injected from the water inlet 11a, water is filled up to the draft line 12g during cooking, heating is started, and when the water temperature confirmation label 11g reaches 40 ° C., the water inlet 11a Continuous water injection is started at 50 and kept at 50 ° C or lower. Depending on the amount of cooking and the cooking temperature, water injection of 0.5 to 0.8 liters per minute will usually stabilize the water temperature at 50 ° C or lower, but if the temperature rises, the injection amount can be increased. The low temperature region including the result storage unit 12c is always kept at 70 ° C. or lower. The correlation between these temperatures has been sufficiently verified. The cooling tap water is allowed to flow from the drain port 11b during cooking to a sink or the like by a hose.
After cooking, the oil may wait for the temperature to drop naturally, but if the water level adjusting plug 11d is replaced with the cooking outlet 11b and water is poured, the water level rises to the outlet 11c at the end, and the cooling effect by running water As a result, the temperature of the oil decreases in a short time.

After the temperature of the oil has dropped, remove the control box 14 from the casing / water tank 11, then take out the oil tank 12, and slowly lift the end of the oil tank 12 opposite to the direction in which the reservoir 12c swells up to a maximum of 90 degrees. Then, the oil removed from the fried residue and moisture is taken out of the oil tank. In addition, since the vibration motor 14c is provided, although the inclination angle of the bottom part of the low temperature oil tank 12b is small, the fried residue and moisture do not remain and fall to the storage part 12c. As a result, since the oil containing fried residue and water remains in the reservoir 12c, this time it is tilted in the opposite direction, and at this time, the mesh or filter paper is passed through and taken out to the external container. Apart from things, this oil is also suitable for reuse.
If the fried cooking method by this invention is performed using the structure by Example 2 as mentioned above, the effect of invention can be acquired similarly to Example 1. FIG. Moreover, by lowering the temperature of the oil in a short time, it is not possible to wait for the temperature of the oil to drop, and accidents caused by working at a high temperature can be reduced.

It is a front view of Example 1 by the present invention. It is a side view of Example 1 by the present invention. It is a top view of Example 1 by the present invention. It is a top view of the heater and convection prevention part support structure of Example 1 by this invention. It is a top view of the convection prevention part of Example 1 by the present invention. It is a top view of the purification | cleaning part of Example 1 by this invention. It is a block diagram of Example 2 by this invention.

DESCRIPTION OF SYMBOLS 1 Housing | casing 1a Partition plate 1b Heat-resistant heat insulating material 1c Upper housing | casing space 1d Leg part 2 Oil tank 2a Cooking oil surface 2b High temperature oil tank 2c Heater 2d Heater lower convection area | region 2e Convection prevention part support structure 2g Low temperature oil tank 2h Oil tank bottom 2i Accumulation part 2j Discharge port 2k Open / close valve 2l Operation rod 2m Cooking temperature sensor 2n Drain pipe 2o Heater mounting part 2p Food fall prevention net 2q Warning sound generator 2r Low temperature area sensor 3 Water tank 3a Water injection pipe 3b Overflow discharge pipe 3c Water tank drain pipe 3e Water injection switch 4 Purification section 4a Deep-fried debris separation section 4b Fine solid filter 4c First sedimentation tank 4d Second sedimentation tank 4e Third sedimentation tank 4f Precipitation water drain pipe 4g Purification section wheel 4h Hole 4j Slit 5a Power supply Box 5b Solid state relay 5c Electromagnetic switchgear 5d Display / control box 5e Display 5f Control board 6a Oil supply hopper 6b Lid 6c Oil supply pipe 11 Case / water tank 11a Water injection port 11b Drain port 11c at cooking end Drain port 11d Water level adjustment plug 11e Check window 11f Control box support structure 11g Water temperature check label 11h Leg 12 Oil tank 12a High temperature oil tank 12b Low temperature oil tank 12c Storage section 12d Spout 12f Cooking oil surface 12g Cooking water line 13 Heater 14 Control box 14a Temperature setting dial 14b Power cord 14c Vibration motor 15 Lifting basket 15a Handle A Front B Rear C Tap water

Claims (4)

A fryer with an oil tank and a heater in the middle of the oil tank, the upper part from the heater being a high-temperature oil tank and the lower part being a low-temperature oil tank, the low-temperature oil tank has a cooling tank and / or a cooling pipe, and the lower part of the low-temperature oil tank Has a slope and a low temperature region. 2. The fryer according to claim 1, further comprising a pipe and / or a valve or a plug for discharging fried residue and moisture from a low temperature region. The fryer according to claim 1 or 2, wherein a structure having a gap with an opening ratio of 20 to 80% with respect to a horizontal cross-sectional area of the oil tank is provided in a low-temperature oil tank 3 mm or more below the lower end of the heater. A heater is provided in the middle of the oil tank, and the oil in the low temperature oil tank below the heater is indirectly brought into contact with water during cooking in the high temperature oil tank above the heater, so that the oil temperature in the low temperature region is 80 ° C or lower. A fried cooking method characterized in that fried residue and moisture are precipitated in a low temperature region and discharged continuously or intermittently together with oil, or stored until the end of cooking.