JPH06109256A - Cooking method - Google Patents

Abstract

PURPOSE:To provide a cooking utensil which is capable of estimating the degree of cooking from the consumption of oxygen when oxidation and decomposition take place in the passage of gas generated from a foodstuff, and further deciding a menu from time changes of an inherent physical quantity and performing automatic cooking without variability. CONSTITUTION:This cooking method is designed to determine the end of cooking from a determination method 1 which is based on foodstuff temperature (T) during cooking, foodstuff weight (m), heating time, foodstuff temperature time gradient and weight time gradient in a cooking utensil capable of being heated with high frequency or a heater and a determination method 2 which is based on oxygen concentration changes caused by oxygen cracking of gas generated from the foodstuff and enables automatic cooking to be made without variability in a desired cooking quality and simplifies the operation of cooking utensils.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooking method for automatically heating and cooking food.

[0002]

2. Description of the Related Art Regarding automatic cooking of food, humidity,
Many methods using various sensors of gas, temperature, weight, and light have been put to practical use in cookers.

For example, as in Japanese Examined Patent Publication No. 4-8687, a weighing scale and a gas sensor are used together to determine the cooking end timing based on the combination of the coefficients α and β, and the automatic cooking is performed.

[0004]

However, the above-mentioned conventional techniques have the following problems.

An error occurs in the measurement of weight due to variations in containers and foods, and in gas detection, variations in the amount of gas generated and variations in gas passages cause error, which causes variations in cooking conditions.

The present invention is to solve the above-mentioned problems. When the cooking degree of food is added to the physical quantity such as weight and temperature of food and the cooking time, the gas generated from the food is oxidatively decomposed in the exhaust passage. It is an object of the present invention to provide a cooking method in which the cooking degree can be estimated from the oxygen consumption amount, and the menu can be determined from the time change of the intrinsic physical quantity, and the automatic cooking with less variation can be performed.

[0007]

In order to solve the above-mentioned problems, the cooking method of the present invention is a cooking device capable of high-frequency heating or heater heating, wherein the food temperature during cooking, the food weight, the heating time, The determination method 1 based on the temperature time gradient of the food and the time gradient of the weight and the determination method 2 based on the oxygen concentration change that changes due to the oxidative decomposition of the gas generated from the food determine the end of cooking, and the controller The heating means or the heater heating means is controlled.

[0008]

The present invention has the following functions due to the above-mentioned structure.

The amount of heat of the food in the cooking chamber is determined by the absolute temperature of the food, the mass of the food and the specific heat of the food.

On the other hand, foods are cooked by heating and show a mass change and a temperature change due to dehydration and the like, so that the heat quantity of the foods also changes. This change in the amount of heat is a function of cooking time and is related to the quality of cooking. This change in heat quantity is
Automatic cooking becomes possible by knowing from the measurement of cooking time.

Since most of the gases generated from the food being cooked are hydrocarbon compounds other than steam, they can be oxidatively decomposed in air using a catalyst. Oxygen in the atmosphere is consumed by the oxidative decomposition, and the amount of oxygen decreases.

The amount of generated gas serves as a measure of the cooking condition based on the chemical change of food, and the oxygen consumption also increases in proportion to the gas amount. Therefore, knowing the cooking condition by knowing the oxygen consumption. Is possible.

[0013]

EXAMPLES Examples of the present invention will be described below.

The present invention relates to a cooking method in which cooking is performed by controlling high-frequency heating means or heater heating means with a controller.

First, the determination of the end of cooking based on the amount of heat of food will be described. Assuming that the amount of heat of food is Q, the temperature of food (absolute temperature) is T, the mass of food is m, and the specific heat of food is c, then Q = m · c · T Formula-1 During cooking, Q is a time function of m and T. Therefore (for simplicity, it is assumed that c is constant), the content of the time change of Q is expressed as follows.

DQ / dt = c · {(dm / dt) · T + m · (dT / dt)} Formula-2 Here, since the food mass m decreases with cooking time, the first term on the right side of Formula-2 The differential term of is negative. In this case, most of the mass change is due to the decrease of water content. Also,
Since the food temperature T increases with cooking time, the differential term of the second term on the right side of Expression-2 becomes positive.

On the other hand, at the start of cooking, the temperature of the food is low and the decrease (evaporation) of water is small. On the other hand, the food temperature rises rapidly by being heated (of course, there is a difference in temperature rising speed inside and outside the food).

It is considered that the amount of heat absorbed by the food is large during cooking and the amount of heat absorbed is small near the end of cooking. In other words, near the end of cooking, the heat balance reaches equilibrium, and in order to maintain that equilibrium, the evaporation of water from food increases.

As described above, in the equation-2, the second term on the right side becomes dominant at the start of cooking, and the first term on the right side becomes dominant near the end of cooking. Therefore, if the value (Q) of the expression-1 is plotted against the cooking time (t), a convex curve is formed, and the time indicating the peak position thereof is a standard for determining the cooking end.

Next, the actual cooking will be described based on the above concept. Here, a commercially available oven microwave oven was used as the cooking device, and grilled fish (saury) was selected as the cooking menu.

FIG. 1 shows changes with time of the heat quantity Q, the weight (as mass) m, and the temperature T of grilled fish. It can be confirmed that the heat quantity Q is convex with respect to time. Near this peak time, the quality of the baked fish was good.

Here, the initial weight is 100 as the weight m.
The relative value of the weight at each time is used. This is because the relative value can absorb the shape change and the difference between the menus rather than the absolute value.

In addition, practically, it is difficult to measure the net weight of food in consideration of the use of the container. Therefore, if possible, it is preferable that the food heat amount Q be a convex curve including the weight of the container. In the expression-2, the absolute value of the first term on the right side becomes small, but since (dm / dt) of the first term is not a large value originally, it is not so greatly affected as a whole. Therefore, it should be possible to make a judgment including the container weight.

When the time change of the heat quantity Q was confirmed by actually using the weight in FIG. 1 as the weight including the container, it was found that it was a convex shape and its peak position (time) was almost unchanged.

Next, the determination of the end of cooking based on the oxygen consumption will be described. Easily Scheme upon oxidative decomposition generated gas expressed as _{aC x H y O z + bO} 2 → cC x · H y · O z + dCO 2 + eH 2 O Scheme-3. It is considered that the generated gas is based on the chemical change of food when heated.

An oxidation catalyst is required for the above reaction, and as the catalyst, for example, a porous catalyst body as disclosed in JP-A-03-258346 is suitable. Further, although the catalyst body is provided in the gas exhaust passage, it is preferable that a simple heater is provided near the catalyst body because the reaction temperature may not be sufficiently reached. A temperature of about 300 ° C. is sufficient.

Further, since the oxygen concentration in the exhaust passage, which changes due to the above reaction, can be measured by a limiting current type zirconia oxygen sensor or the like, the cooking condition can be estimated by tracking the change over time in the oxygen concentration.

Depending on the cooking menu or the amount of food, the amount of gas generated may be small and the change in oxygen concentration may be small. Therefore, it is necessary to optimize the method of arranging the catalyst body and the oxygen sensor in the exhaust passage. . For example, the catalyst body and the oxygen sensor may be integrated or the reaction space may be controlled.

FIG. 2 is a curve showing the amount of oil smoke produced during the cooking of grilled fish, which has already been described. The oil smoke was regarded as particles and the amount generated was measured with a dust meter. It can be seen that the amount of oily smoke increases with the passage of time and a large amount of oily smoke is generated at the end of cooking (about 20 minutes).

By oxidizing and decomposing this oily smoke, the oxygen concentration in the exhaust passage decreases, and the oxygen consumption amount can be known. The total amount of oxygen consumed at this time or a typical amount of oxygen consumed, for example, the amount of oxygen obtained by time integration of the consumed amount during cooking or after the oil smoke rapidly increases is proportional to the initial amount of food.

Therefore, it is possible to determine the end of cooking by knowing the relative oxygen consumption amount per unit weight for each cooking menu in advance and comparing the initial weight of food with the oxygen consumption amount during actual cooking.

The present invention has both of the two types of cooking end determination methods as described above, but they are determination methods based on physical changes and chemical changes, respectively, and supplement the weaknesses of both.

In order to actually apply it to a cooking device, it is necessary to previously set a judgment criterion for the correlation between the above two kinds of judgment methods for each cooking menu. However, as compared with the conventional methods, each method has a relative determination standard and is less susceptible to an error in each cooking, and therefore automatic cooking without variations can be performed by combining both methods.

The grilled fish has been described above as an example, but other menus can be automatically cooked similarly. For example, it goes without saying that the grill menu mainly consists of baking,
Sponge cake, fruit cake, bread roll, pizza,
The same goes for oven menus such as pies and chows.

However, with respect to the time change of the heat quantity Q, the position of the peak or the rate of decrease of Q after reaching the peak varies depending on the menu, and there is a difference in the heating time required after reaching the peak. On the other hand, it is also understood that the menu can be determined by recognizing the pattern Q of each of the above menus.

Therefore, if the cooking device is provided with at least the pattern recognition means and the heating control means associated therewith, the automatic cooking including the menu determination becomes possible. Conventionally, the menu determination part has been dependent on external input by key operation or has a complicated structure using several kinds of sensors such as an optical sensor, but it is obvious that it will be simplified.

[0037]

As described above, according to the cooking method of the present invention, the following effects can be obtained.

In addition to the cooking degree of the cooked food, the physical quantity such as the weight and temperature of the food and the cooking time, the cooking degree is estimated from the oxygen consumption when the gas generated from the food is oxidized and decomposed in the exhaust passage. Further, by judging the menu from the unique physical quantity, it is possible to perform automatic cooking with less variation, which also simplifies the operation of the cooker.

[Brief description of drawings]

[Figure 1] Time-dependent curve diagram of physical quantities (heat quantity, weight, temperature) of grilled fish (samma)

FIG. 2 is a diagram showing changes over time in the amount of oil smoke produced by grilled fish (sangma).

Claims (3)

[Claims] 1. A cooking device capable of high-frequency heating or heater heating, wherein the food temperature during cooking, the food weight, the heating time, the temperature time gradient of the food, and the determination method 1 based on the time gradient of the weight, and the food A method for determining the end of cooking according to the determination method 2 based on a change in oxygen concentration that changes due to the oxidative decomposition of the gas generated from, and controlling the high frequency heating means or the heater heating means by the controller. 2. The cooking method according to claim 1, wherein the food is discriminated from the sum of the component including the temperature-time gradient and the component including the weight-time gradient. 3. The oxidative decomposition means for oxidative decomposition of the gas, comprising an exhaust passage for the gas, a catalyst body containing an oxidation catalyst provided in the exhaust passage, and a heater for heating the catalyst body. Cooking device.