JPH03240465A - Method and device for preparing boiled egg with microwave - Google Patents

Abstract

PURPOSE:To enable to prepare a delicious boiled egg such as perfectly boiled egg or half-boiled egg in a much short time by receiving an egg in a heat- resistant container, pouring hot water up to a constant volume and subsequently setting a prescribed microwave irradiation time. CONSTITUTION:Eggs 1 are received in a heat-resistant container 1 well penetrating microwaves, and hot water is poured in to the container 1 until the total volume of the eggs 9 and the hot water reaches a constant volume. A microwave irradiation time for the next step is simultaneously set to prepared boiled eggs, while employing the measured value of a hot water temperature-lowering degree after a constant time as a barometer. A device comprising a container 1 controlling the volume of the poured hot water and also holding the eggs is preferably employed, the container 1 having a portion projected at the central portion of the lower bottom surface thereof in a conical volcano-like shape, semi-annular containers disposed around the projected portion and a funnel-like hot water-pouring opening for controlling the flow volume of the hot water at the top of the projected portion.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a method and apparatus for making omelets in a microwave oven.

2. Description of the Related Art In the past, it was believed that eggs could not be made in a microwave oven because they would explode if heated with microwaves. Recently, a method has been announced in which an infrared temperature sensor is installed inside a microwave oven to directly control the temperature of water to make eggs. A device that heats water and eggs using electric heat has also been announced.

These methods heat the eggshell only by direct heat conduction by immersing it in hot water, so it takes a long time to make the eggshell, which is no different from heating the eggshell in a pot. Therefore, it is not very popular.

Problems that the invention aims to solve Even with the method of heating eggs and hot water in a pot, the number of fully ripe eggs is 1.
It takes more than 2 minutes to make hot spring eggs.

Both the microwave method and the electric heating method require 12 minutes for fully ripened eggs and 30 minutes for hot spring eggs, even if hot water is used. There is not much difference between this method and using a pot. The reason why it takes such a long time to heat the egg is that it takes time for the heat to reach the inside of the egg since the egg is heated only by direct heat conduction through the eggshell using hot water. Currently announced microwave oven heating uses an infrared temperature sensor to measure the water temperature once it reaches a certain temperature (85°C for ripe eggs, 65°C for hot spring eggs) and then turns the power on and off to set the water temperature to the specified temperature. A method has been adopted to maintain the Therefore, after the specified temperature is reached, hardly any microwaves are emitted, and penetration heating by microwaves cannot be expected, which is not much different from heating by electric heat or a pot. In contrast, the present invention radiates microwaves continuously during heating, concentrates them on eggs, and maximizes the heating characteristics of microwaves by temperature, thereby reducing heating time in a much shorter time than conventional methods. It made it possible to make eggs with your arm.

Measures to solve the problem 1) If the total amount of eggs and hot water is kept constant by setting the level, the apparent specific heat of eggs and water is approximately equal, so the heating load will depend on the number of eggs, the temperature, and the temperature of the hot water used. is determined.

2) The temperature decreases rapidly until the end of pouring the hot water, and then gradually decreases. Therefore, the approximate heating load can be determined by measuring the temperature of the hot water when it is finished pouring.

3) Set the heating time for fully ripe eggs (soft-boiled eggs) and hot spring eggs according to the measured water temperature. In the case of a home microwave, the microwave output is approximately 50QWatt for a fully ripened egg, and approximately 200W for a hot spring egg.
It is tt.

4) If the amount of hot water used is too small, the eggs will crack and the yolks will pop out, while if too much water is used, it will take a long time to heat. Therefore, the level is determined by experimenting with the most appropriate amount of hot water. If the number of eggs used is up to 5 in the case of a home microwave oven, the appropriate total amount of hot water and eggs is 850c.c.

For business use, you can set it separately.

5) Maximize the benefits of microwave osmotic heating by concentrating microwaves using a specially shaped container and placing eggs in that location.

6) In particular, the higher the temperature of the water used, the higher the heating efficiency.

This is because there is a lot of direct heat conduction to the eggs through the hot water, and the characteristics of microwaves for water are optimal for non-heating.

7) Generally, eggs are soaked in hot water right after they are taken out of the refrigerator to prevent the eggshells from cracking.

Effects and examples The operation will be explained based on an example.

1) Fig. 1 shows the home-use microwave oven of the present invention. Although the figure shows the case of polypropylene resin, heat-resistant glass (Pyrex) or ceramic materials may also be used.

In the figure, 1... Container 2... Lid 3... Egg holder 4... Funnel for pouring hot water 5... Thermometer 6...Level 7...Flow of poured hot water 8...Egg a...Temperature measurement point b on top of egg white...Egg yolk Temperature measurement point C...Temperature measurement point below the egg white If an infrared temperature sensor is installed in the range to directly measure and control the water temperature, (5) is not necessary.

In the figure, the hot water poured from D in (4) falls in the direction of (7), passes through the narrow part shown in E in (3), and reaches F. In this way, the egg sinks into the water gradually from the bottom to the top over time. By regulating the area through which the hot water passes through this narrow part E, the hot water pouring time is 25 to 30 minutes.
Set it to seconds. For this reason, even if you use boiling water, the eggs will not break. In the case of manual operation, set the eggs in (1), pour in hot water, measure the temperature of the water in (5), and set the heating time on a timer. If you have an infrared temperature sensor, when you put the container in the microwave it will automatically read the water temperature and set the heating time.

? ) Figure 2 shows how the temperature of eggs and water is measured in the container shown in Figure 1. (The lid and egg holder are not shown (5) (6).) In the figure, 12... Container 13... Turntable 14... Egg 15... . . . Range 16 . . . Distance tube (determines the temperature measurement position of the egg).

3) In Figures 3 and 4, using the egg holder of the present invention shown in Figure 1, using water at 20°C according to the measurement method shown in Figure 2, The temperature rise curve when making fully ripened eggs is shown for the case of . Figure 3 measures the temperature of each part of the egg (a, b, c) for one egg, and Figure 4 measures the temperature of each part of the egg (a, b, c) for four eggs. The temperature of each part is almost parallel and the graph increases as one. This shows that the heating properties (apparent specific heat) of water and eggs are almost the same. Next, Fig. 5 shows the components of the egg, their proportions, and specific heat as a table. Calculate the apparent specific heat of the egg based on Figure 5. However, the specific gravity of eggs is approximately 1.1.

(74,7x 1 +11.2x0.49+12.3x
0.42+1.8×0.42) Xl, 1 = 100
XS From this, the apparent specific heat of the egg S = 0.95 Kcal/kg
The approximate value of the heating load is determined by measuring the drop in temperature when hot water is poured at ℃.

4) Figure 6 shows the drop in water temperature when boiling water is poured, depending on the water temperature used and the number of eggs. The total cost of eggs and hot water is 850c, c, and the eggs are medium size. Egg temperature, egg size (L, M
The drop in water temperature differs depending on the size). In the present invention, the temperature of the hot water used is 90°C or higher. It takes 25 to 30 seconds to finish pouring the hot water, but the temperature of the hot water drops rapidly during this time, as shown in the figure, and after that the temperature decreases gradually. 27.5
Shows the water temperature as seconds pass.

Therefore, you can determine the approximate heating load by measuring the temperature when you have finished pouring hot water.

5) The heating curve for making fully ripened eggs using the container shown in Fig. 1 and measuring the water temperature and the temperature of each part of the egg (a, b, c) as shown in Fig. 2 is shown in Section 7.8. Shown in Figure 9. The temperature of unused water is 100℃ in Figure 8, 95℃ in Figure 9, and 9 in Figure 10.
This is the case at 0°C. In the figure, the solid line indicates the case of one egg, and the dotted line -----1 indicates the case of four eggs.

As is clear from the figure, the heating time to make fully ripened eggs is determined by the number of eggs, temperature, and the temperature of the water used, which is determined by the drop in water temperature measured at the time of pouring.

Thus, the heating time for producing fully ripened eggs using the method of the present invention is 3 minutes at 80°C if the reduced water temperature is 90°C or higher.
If the temperature is ~89°C, set it to 3°5 minutes, and if the temperature is 79°C or lower, set it to 4 minutes. In the case of soft-boiled eggs, it is 1.5 to 2 minutes.

6) Next, the heating curves when hot spring eggs are made using the same method are shown in Figure 10 when the water temperature used is 95°C and in Figure 11 when the water temperature is 90°C. For hot spring eggs, use hot water of 90°C or higher.

The output of the range is 200 watts. In the case of hot spring eggs, if the microwave power is high, the egg white will solidify before the yolk, so set the power low. The measurement points and curves for 1 and 4 eggs are the same as for fully ripe eggs.

In the case of hot spring eggs, the egg white needs to remain fluid and the yolk needs to be almost solid, which requires delicate temperature adjustment. For this,
The heating time is determined from two factors: the temperature of the water when poured and the number of eggs.

FIG. 12 shows a graph of heating time determination.

For example, if the water temperature when pouring 4 eggs is 76°C, in the graph of 3 (for 4 eggs), go above the water temperature G and the intersection with the graph) -1. Turn horizontally to the left 1
At this point, the heating time is determined to be 6 minutes. ±0 depending on firmness preference
．． You may add or subtract 5 minutes.

7) In the present invention, a container with a special shape is adopted and a hot spot effect is adopted.

(1) Hot spot effect (9) (10) In microwave heating, the electric field concentrates on a certain part depending on the size and shape of the container, and that part is heated strongly. This is called the hot spot effect. Therefore, in the case of hand-picked eggs, if the eggs are placed in a place where this electric field is concentrated, the heating rate will be faster, and the eggs will be of uniform quality.

(2) Shape of hot spot depending on the shape of the container Figures 13 to 16 show the state of hot spot formation depending on the shape of the container. Theoretical analysis of hot spot formation is the 13th
Since it is complicated and impossible to see anything other than a diagram, a starch paste dyed with iodine is used to confirm that the paste loses color and becomes transparent at 60°C to 70°C. The area in the container where the hot spot occurred fades and becomes transparent, and the area expands thereafter. In the figure, the hatched areas are hot spots.

In FIG. 13, it occurs in the center in the case of a spherical shape.

Figure 14 shows that in the case of a small cylinder with a thickness of (11), such as a petri dish, it occurs concentrically around the center and periphery. FIG. 15 shows the case of a cylinder with a large depth, in which the upper and lower portions occur.

In the case of a cylindrical container with a spherical bottom, FIG. 16 shows a large spot on the bottom and several spots on the top at the same time. Therefore, in this case, heating is the fastest and the temperature is the same throughout.

(3) The egg holder of the present invention shown in FIG. 1 was invented with the effect shown in FIG. 16 in mind. FIG. 17 shows the spots generated at this time.

(17) is a hotspot. The egg is thus in the hotspot.

(4) FIG. 18 shows spots generated on a cylindrical container having the same external dimensions as the container of the present invention.

(The top part is cut). As is clear from the figure, only the bottom part of the egg (C) enters the spot, while the other top part (a) and yolk (b)
) the temperature becomes higher. The heating curve of fully ripened eggs in this case is shown in FIG. The distinction between 1 egg and 4 eggs is the same as the heating curve shown in (12).As is clear from the figure, C
The temperature of is always higher than a and b, and the reached temperature is higher than the hot water temperature. Egg yolk (b) is undercooked. This is a temperature difference caused by the spot, and the eggs harden unevenly, which is a problem especially in the case of soft-boiled eggs and hot spring eggs. Decreases the quality of eggs.

8) Figure 20 shows how the microwave absorption and permeability of water change significantly depending on the water temperature when water is irradiated with microwaves.

The frequency is 2450Mt12. In the figure, 18・
... ξ・tan δ 19 ... Indicates half-life depth (D). The electric power (microwave) absorbed by water is shown by the following equation. P valve 5/9×ξ=tanδXfXE2
XIO-" (Wajt/m3) formula, f...
- Dielectric constant tan δ... Dielectric loss tangent f... Frequency E... Electric field strength Of these, f and E are constant, and ξ and tan δ vary depending on the water temperature. Therefore, the power absorbed by water is proportional to ξ・tanδ(18〉). Also, the half-life depth means that the microwave incident on water is absorbed by the water and the transmitted power becomes smaller, but the thickness is just below the point of incidence. It shows the depth at which it becomes half of that.Therefore, the larger the half-life depth, the better the penetration into the egg and the greater the internal heating.As is clear from the figure, (18) ξ・tan δ and (19) D increase depending on the water temperature. The higher the water temperature changes, the less electricity is absorbed by the water and the better the permeability becomes.In other words, the warmer the water is from the beginning, the less electricity (microwaves) will be absorbed by the water.
The amount that penetrates into the egg and is absorbed becomes large, making it extremely advantageous for non-heating.

Also, the greater the difference between the temperature of the egg and the water, the greater the direct heat conduction through the eggshell. In this way, the hotter the water, the faster it can be heated.

9) In the present invention, hot water of 90°C or higher is used, but this is possible by using a special retainer with a funnel as shown in Figure 1. (13) (14)

By making maximum use of the spot effect and microwave characteristics, it is possible to make handmade eggs in a much shorter time compared to heating using a commercially available egg cooker or pot. For example, in the case of fully ripened eggs, 12 minutes is 3 to 4 minutes, which is 1/4 to 1/4 of the conventional time.
It can be made in 1/3 of the time. Also, in the case of hot spring eggs,
It can be made in 5 to 6 minutes instead of 30 minutes, which is 1/6 to 115 times the time compared to conventional methods.

2) Since the present invention places the egg in the center of the hot spot, the egg is heated evenly and quickly. On the other hand, in the case of commercially available oven-baked eggs, a method is used to keep the water temperature constant in order to avoid unrestricted heating of the eggs due to spot heating, which requires a long heating time.

3) When heating water and eggs with microwaves, by taking advantage of the fact that the heating characteristics (apparent specific heat) of water and eggs are roughly the same, the effective volume including water and eggs is kept constant (
The heating time (timer) can be set depending on the temperature of the water when poured. Therefore, it is not necessarily necessary to provide an expensive infrared temperature sensor in the range. Regardless of whether the microwave is single-function or multi-function (automatic), you can make fully-ripened eggs (soft-boiled eggs) and hot spring eggs using only the arm separate container.

4) The arm separate container of the present invention continuously irradiates both fully ripe and hot spring eggs with microwaves. Therefore, the sticky consistency of the egg yolk, which is a characteristic of microwave-heated eggs, is very high, and the eggs are especially delicious when used as soft-boiled eggs or hot spring eggs.

5) The egg holder of the present invention has a simple structure, has few parts, and can be provided at a very low price. Moreover, the range used can be either single-function or multi-function, and can be treated as a part of the range.

[Brief explanation of drawings]

Figure 1 is a separate arm according to the present invention. Figure 2 is a temperature measuring method. Figure 4 is a heating curve for a fully ripened egg. Figure 5 is the composition and specific heat of the egg. Figure 6 is the temperature measurement method. Temperature drop curve when pouring water No. 7.8.
Figure 9 is the heating curve for fully ripened eggs Figure 10. Figure 11 is the heating curve for hot spring eggs. Figure 12 is the heating time determined by the decreasing water temperature. Figure 20 shows the heating curve of fully ripened eggs using a commercially available container. (17) ゛＼V JP-A-3 240465 (8) ``9 工 d 1 L '' play 931E j 1 eye C 1 L '' bih go l knee! -[1- Procedural auxiliary equipment 1. Display of the case 1990 Patent Application No. 36957 2, Name of the invention Method for making omega by microwave and apparatus for making omega by microwave 3, Person making amendment Relationship to case Postal code

Claims (1)

[Claims] 1) A large number of eggs are placed in a container made of a material that is heat-resistant and transparent to microwaves, and boiling water is poured into the container to a set level, and the eggs are heated at the temperature indicated at that time. A method for making eggs using microwaves, which is characterized by continuously irradiating microwaves for a set time. 2) From an egg holder consisting of a ring-shaped container with a semi-circular bottom, which is made by cutting out the center of a cylindrical container made of a material that is heat-resistant and transparent to microwaves, and a funnel for pouring hot water into the top. A device for making eggs using microwaves, which is characterized by: