JP2009219674A - Rice cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rice cooker which can cook rice with a good taste wherein a sweetness and a good flavor are induced without requiring labor for the setting by a user by a smaller consumption power amount than the present condition. <P>SOLUTION: A controlling means which performs a series of cooking motions makes 40 to 60°C being the optimal activity temperature zone of an enzyme contained in rice progress in steps during 30 minutes in an immersion process in rice cooking by setting an initial set value of a rice cooking sequence storage means at a rice cooking sequence having a longest rice cooking time among from stored rice cooking sequences. Thus, the decompositions from starch to a saccharide, and from protein to an amino acid are accelerated, and cooked rice with the good taste for which the sweetness and the good flavor owned by rice itself have been induced is cooked. Meanwhile, this rice cooker can cook the tasty cooked rice by the less consumption power amount because an water absorbing effect can be obtained by long time immersion at low temperature. The rice cooker of this constitution is provided. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rice cooker mainly used for home use.

  In order to cook rice deliciously, it is said that it should be boiled at high heat and cooked with enough heat to blow down, as in the legend from the Edo period, "In the beginning, chopp choro napapa-don't take the lid even if you cry baby" Yes.

  The current microcomputer-controlled rice cooker for home use has a built-in microcomputer as a standard rice cooking sequence to cook white rice into delicious rice. In general, follow the legend of “Introduction Choro Choro ~”, the soaking process to absorb the water in the rice, the cooking process to raise the temperature in the pan at once, and the boiling process to maintain the boiling of rice starch It consists of a boiling maintenance process to gelatinize and cook, and an uneven process to steam the cooked rice and finish the pan evenly. After washing the rice, adding water and pressing the switch, it takes about 30-60 minutes The rice will be cooked automatically. In addition, the stronger the cooking power, the better the taste of the rice. In the cooking process, it is said that cooking with stronger heating power is more delicious (see, for example, Patent Document 1).

In modern times, however, the taste of rice is demanded, while consideration for the global environment is also demanded. The future challenge is to reduce the amount of power consumed during use as much as possible and to reduce CO ₂ emissions. For the purpose of reducing the amount of power consumed during rice cooking, there is also an energy saving rice cooking mode provided so that heating in each process is performed over a long time with electric power weaker than usual (see, for example, Patent Document 2).
JP-A-8-164066 Japanese Patent No. 3299919

  However, as a matter of course, when the heating power at the time of cooking is lowered, the cooking time becomes longer and the taste of rice is lowered. The present invention was made in order to solve the above problems, and even when cooking with less power consumption than before, the taste of sweetness and umami was extracted without lowering the taste of rice. The purpose is to get rice.

  In order to solve the above problems, the rice cooker of the present invention was heated at the optimum temperature range of the amylolytic enzyme that produces oligosaccharide, and then heated at the optimum temperature range of the proteolytic enzyme that produces higher amino acids. Later, by having a rice cooking sequence in the submerged process of heating in the optimum temperature range of the amylolytic enzyme that produces higher glucose, it is possible to obtain rice with good taste that brings out the sweetness and taste of rice itself, and more Rice can be cooked with low power consumption.

  In general, tasty rice is said to have a moderate sweetness with no damage to the surface of the grain, and it is said that it has moderate sweetness to the center of the grain. .

In particular, the cause of sweetness is saccharides such as glucose, which is produced when starch is decomposed by amylolytic enzymes, and it is said that the more monosaccharide glucose with a smaller molecular weight, the more sweet rice is. The process was often set to about 55 to 60 ° C., which is the temperature at which the amylolytic enzyme that decomposes to glucose works most effectively (optimum temperature).

  On the other hand, it is desirable that this temperature is low from the viewpoint of reducing power consumption, but for the reasons described above, the rice becomes less sweet and the taste is poor.

  However, the component exhibiting sweetness is a component in which not only glucose but also amino acids feel sweetness. Therefore, even if glucose decreases, if the amino acid increases, good taste can be maintained without feeling that the sweetness of the final cooked rice has decreased.

  The optimal temperature of the proteolytic enzyme that produces amino acids is around 45 ° C. Even if the amount of glucose produced is reduced by reducing the power consumption by setting the temperature of the water immersion process to 45 ° C, the amount of amino acids produced By increasing the value, good taste can be maintained without reducing the sweetness of the final cooked rice.

  The rice cooker of the present invention cooks rice with less power consumption than the present state, increases the amount of amino acids generated by activation of rice proteolytic enzymes, and provides a good-tasting rice from which sweetness and umami are extracted. be able to.

  1st invention is a main body, the pan accommodated in the inside of the said main body, and the pot which puts rice and water, the openable / closable outer cover which covers the upper opening part of the said pan, the heating means which heats the said pan, and the said pan A pan temperature detection means for measuring the temperature of the rice, a rice cooking sequence storage means for storing a cooking sequence comprising at least one of a soaking process, a cooking process, a boiling maintenance process, and an unevenness process, and a series by controlling the heating means. The rice cooking sequence storage means is heated at the optimum temperature range of the amylolytic enzyme that produces oligosaccharides, and then the optimum temperature of the proteolytic enzyme that produces higher amino acids than that. Since the rice cooking sequence of the water immersion process is heated in the optimum temperature zone of the starch-degrading enzyme that produces higher glucose after heating in the belt, A rice cooker that can maintain the optimal activity temperature of contained proteolytic enzyme at 45 ° C., thereby extracting sweetness and umami from amino acids to obtain a good-tasting rice and cooking rice with less power consumption. Can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the present embodiment.

(Embodiment 1)
FIG. 1: shows the block diagram of the rice cooker in the 1st Embodiment of this invention, and is an example of an electric type IH heating rice cooker. In FIG. 1, the main body 1 is detachably stored in a pot 2 for containing rice and water, and a heating means 4 for heating the pot 2 disposed so as to face the bottom side surface of the pot 2, The upper surface opening of the main body 1 is provided with an outer lid 3 that can be freely opened and closed so that the pan 2 can be attached and detached. In addition, the pan temperature detecting means 5 is arranged around the bottom center of the pan 2, the control means 7 inputs the detection temperature of the pan temperature detecting means 5, and controls the heating amount of the heating means 4 to heat the pan 2. Cooks rice and water in Shiretna 2. Furthermore, the rice cooking sequence memory | storage means 6 which memorize | stored the some rice cooking sequence from which rice cooking time differs is provided.

About the rice cooker comprised in this way, the operation | movement and an effect | action are demonstrated below based on FIG. Fig.3 (a) is a figure which shows a general rice cooking process, FIG.3 (b) is a figure which shows the temperature of the rice in a general rice cooking process. First, as shown in FIG. 3A, a general rice cooking process mainly includes a water immersion process A, a cooking process B, a boiling maintenance process C, and an unevenness process D.

  In the flooding step A, the detected temperature Ta of the pan temperature detecting means 5 is the first predetermined temperature T1 (normally) until the time measured by the time measuring means (not shown) reaches the first predetermined time t1 (normally around 20 minutes). The heating control means 6 controls the heating means 4 so as to be about 55 ° C., and the pan 2 is heated by the heating means 4. The water immersion process is a process for sufficiently gelatinizing the center of the rice in the subsequent steps by immersing the rice in water at a temperature lower than the gelatinization temperature and allowing the rice to absorb water in advance. Around 20 minutes and around 55 ° C. are values that allow water to be absorbed to the center of rice as soon as possible without damaging the physical properties of the rice grains.

  Next, after the water immersion process A is completed, the process proceeds to the cooking process. In the cooking step B, as shown in FIG. 3 (a), the heating means 4 until the detection temperature Ta of the pan temperature detection means 5 reaches the second predetermined temperature T2 (the boiling point of water (usually around 100 ° C.)). Is to heat the pan 2.

  In this step, the heating means 4 is controlled by the temperature detected by the pan temperature detecting means 5, but a lid temperature detecting means for detecting the temperature of the outer lid 3 covering the opening of the pot is provided separately, and the lid temperature detecting means. The heating means 4 can also heat the pan 2 until the detected temperature reaches a predetermined temperature.

  Then, after the cooking process B is completed, the process proceeds to the boiling maintenance process C. In the boiling maintenance process C, as long as there is water in the pan 2, the detected temperature Ta of the pan temperature detecting means 5 is a second predetermined temperature T2 (boiling point of water (usually 100 ° C.) as shown in FIG. The heating control means 6 controls the heating means 4 so that the boiling state is maintained in the vicinity)), and the heating means 4 heats the pan 2. And if the boiling maintenance process C passes, the water in the pan 2 will evaporate, and if there is no water in the pan 2, the temperature of the pan 2 will rise. When the detected temperature Ta of the pot temperature detecting means 5 reaches the third predetermined temperature T3 (above the boiling point of water), it is determined that there is no water in the pot 2 and the process ends. This step is a step of gelatinizing rice starch, and the degree of gelatinization of rice after cooking reaches nearly 100%, but the degree of gelatinization is about 50 to 60% at the end of this step.

  Next, the process proceeds to the unevenness process D. In the unevenness process D, as shown in FIG. 3A, the detected temperature Ta of the pan temperature detecting means 5 is kept at the second time until the time measured by the time measuring means reaches a second predetermined time t2 (usually around 15 minutes). The heating control means 6 controls the heating means 4 so that it is maintained at a predetermined temperature T2 (usually around 100 ° C.), and the heating means 4 heats the pan 2. The unevenness process is a process of gelatinizing rice starch following the boiling maintaining process. At the beginning of the unevenness process, the gelatinization degree was about 50 to 60%, but at the end of the unevenness process, that is, rice cooking At the end, the degree of gelatinization reaches nearly 100%. Through the above four steps, rice cooking is completed in about 45 minutes.

  When such a rice cooking process is executed, the detected temperature Ta of the pan temperature detecting means 5 is shown in FIG. 3A, and the temperature Tb in the pan 2, that is, the temperature of the rice is as shown in FIG. 3B. Temperature transition to.

In addition, FIG. 4 shows the action of each amylolytic enzyme and the proteolytic enzyme and the temperature range at which it works most effectively as data on the enzyme. According to FIG. 4, at 40 ° C., enzyme I acts most effectively and oligosaccharides are produced. Oligosaccharide is a general term for sugars in which 2 to 10 monosaccharide glucoses are bonded to each other, and maltose is a typical example of rice. The taste characteristics are less sweet compared to glucose, but umami and kokumi are felt. Moreover, at 60 degreeC, the enzyme II acts most effectively and glucose is produced | generated from oligosaccharide. Furthermore, at 45 ° C., proteolytic enzyme A and proteolytic enzyme B act effectively. After enzyme A breaks down the protein contained in the rice into small peptides, enzyme B releases amino acids from the end of the peptide. The amino acids produced are glutamic acid and aspartic acid, which are well known as umami ingredients.

  The water immersion process of the conventional general rice cooking sequence is about 20 minutes at 55 ° C., but because the activity of enzyme I is weak, rice with strong sweetness due to glucose produced by the action of enzyme II was cooked. .

  Drawing 2 is a figure showing the rice cooking process of the rice cooker in the 1st embodiment of the present invention. When the user starts cooking, in the water soaking process in which the rice absorbs water in the rice cooking process, it is kept for 15 minutes at 40 ° C., which is the optimum activity temperature zone of enzyme I contained in the rice. Because it is produced, it can bring out the sweetness and taste of rice itself, and can prevent the grains from collapsing due to the low water immersion temperature. After that, by carrying out a water immersion process at 45 ° C. for 10 minutes, which is a temperature higher than this, and is the optimal activity temperature zone of proteolytic enzymes A and B contained in rice, amino acids are produced from the protein to produce umami components Increase. After that, the temperature is higher than this, the optimal activity temperature zone of enzyme II contained in the rice, and a short time high temperature water immersion step at 60 ° C. near the gelatinization temperature zone for 5 minutes, Since water is absorbed in the water immersion process, the water absorption is completed before a large amount of elution due to gelatinization occurs, and the enzyme that works most effectively at high temperatures can be hydrolyzed in a short time, greatly increasing the amount of glucose produced. Without reducing the amount, the sweetness of the rice can be further increased because the amount of amino acids produced is increased by suppressing the collapse of the grains. The control means 7 controls the heating means 4 through the cooking process, the boiling maintenance process, and the unevenness process following the water immersion process, and cooks the food to be cooked in the pan 2.

  FIG. 6 is data regarding the sugar and amino acid contents of the rice cooking course and the cooked rice in the first embodiment of the present invention. When the amount of sugar and amino acid contained in the rice in this embodiment was quantified, the amount of glucose showing sweet taste was reduced compared to the sequence of the conventional example, but the total amount of oligosaccharide showing umami was about 4 times. It has been proved that the taste has been brought out. In addition, the amount of amino acid is increased by 1.2 times, and as a result, an increase in sweetness is observed. As mentioned above, according to this Embodiment, the rice cooker which cooks the rice which pulled out the sweetness and umami which rice itself has to the maximum can be provided.

  In addition, it cannot be overemphasized that the above embodiment can be implemented also in the rice cooker of the other system controlled by a microcomputer.

  In addition, the rice cooking time in this embodiment, the water immersion process and the detection temperature in each rice cooking process, the process time, and the preliminary soaking time and the temperature and time of the low temperature soaking process and the high temperature soaking process are generally preferred tastes. This is an example of implementation when cooking rice, and the numerical value can be changed according to the physical properties and characteristics of the target rice and the situation.

  As described above, the rice cooker according to the present invention can cook good-tasting rice from which sweetness and umami are drawn with less power consumption than the current state, so that it is generally used for both home and business use. Useful as a rice cooker.

The block diagram of the rice cooker in Embodiment 1 of this invention. The figure which shows the rice cooking process of the rice cooker in Embodiment 1 of this invention. (A) The figure which shows a general rice cooking process (b) The figure which shows the temperature of the rice in a general rice cooking process Diagram showing data on enzymes The figure which shows the data regarding the sugar and the amount of amino acids of the rice cooking course and cooked rice in Embodiment 1 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main body 2 Pan 3 Outer lid 4 Heating means 5 Pan temperature detection means 6 Rice cooking sequence storage means 7 Control means

Claims (1)

A main body, a pot for storing rice and water stored in the main body, an openable / closable outer lid covering the upper opening of the pot, a heating means for heating the pot, and a pot for measuring the temperature of the pot Control for performing a series of rice cooking operations by controlling the temperature detection means, the rice cooking sequence storage means storing at least one of the water immersion process, the cooking process, the boiling maintenance process, and the unevenness process, and the heating means. The rice cooking sequence storage means is heated at the optimum temperature range of the amylolytic enzyme that produces oligosaccharide, and then heated at the optimum temperature range of the proteolytic enzyme that produces higher amino acids, Furthermore, it has the said rice cooking sequence of the said water immersion process heated in the optimal temperature range of the amylolytic enzyme which produces | generates glucose higher than it, The rice cooker characterized by the above-mentioned.