JP2000039430A - Method for measuring collapse of formed rice - Google Patents

Abstract

PROBLEM TO BE SOLVED: To evaluate a proper collapse required for formed rice such as a rice ball and hand-rolled sushi by measuring the first inflexion point of force - strain curve by performing the single-axis compression rupture test of the formed rice by a rheometer. SOLUTION: After the first inflexion point of force - strain curve is measured by performing the single-axis compression rupture test of formed rice by a rheometer, the 5 stress - strain scattering diagram of the first inflexion point is created. The first inflexion point is a point when a rice mass starts to collapse due to the weakening of the adhesion of rice particles, a value where the force at the first inflexion point is measured as a breaking strength and strain is measured as breaking strain is linked to the collapse and ball of the formed rice. By using it as an index for indicating a proper collapse or comparing the numeric values, the collapse of the formed rice is examined, selected, and evaluated. Further, the formed rice with a proper collapse can be manufactured industrially. Also, this method is helpful for preventing the collapse of the formed rice being generated due to the move or the like of a manufacturing process line.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the collapse of newly formed cooked rice, and more particularly to a method for quantitatively measuring the collapse of rice cooked on rice balls, nigiri sushi, etc., and a molded rice having moderate collapse and hardness. The present invention relates to a method for producing molded rice having appropriate collapse and hardness based on the method, and a method for producing molded rice having excellent adhesiveness, melting and binding power obtained by the method.

[0002]

2. Description of the Related Art Molded rice, such as rice balls and nigiri sushi, may be eaten immediately after molding, but especially when manufactured and sold industrially, it is rare to eat immediately after molding. It is often stored for a while, transported, refrigerated, or frozen-thawed before being sold and then eaten. For example, if the rice ball is too strong, it is too hard to bite easily with your mouth,
In addition, even after entering the mouth, it does not easily collapse and strains the teeth and cannot be eaten very deliciously.

[0003] On the other hand, if it is weakly broken, it may collapse before storage or before grabbing it with your hand and putting it in your mouth. After all we cannot eat deliciously. This is because the hardness is affected by the type of raw rice, the rice cooking conditions, and the way of squeezing during molding, even if the molding is performed with the same force applied during molding.

[0004] Therefore, there is a demand for a molding method that can be eaten deliciously at the stage of eating cooked cooked rice so that the cooked rice has a degree of collapse and hardness. Furthermore, it is desired that the cooked rice has an appropriate degree of collapse and hardness in relation to various factors required before molding, such as the type of raw rice used and the rice cooking conditions.

[0005] On the other hand, considering from the eating side, during storage,
It does not collapse easily when transported or grasped by hand. Therefore,
The one that does not easily collapse is preferable.

[0006] It is easy to bite a rice ball that is grasped by hand with a mouth. Therefore, it is not preferable that the sheet is easily broken and easily separated, so that an appropriate degree of breaking is required.

[0007] It collapses easily in the mouth (that is, it is easy to melt). On the other hand, it is not preferable that it is easily collapsed in the mouth, and a moderate crunch and a moderate collapse that is easy to melt are required.

The above-described well-balanced molded rice breaks, and rice cooked such as rice balls having hardness are required. For the evaluation, objective indicators corresponding to the collapse and the hardness are linked. And its quantitative range are particularly required by manufacturers.

Heretofore, various types of rice cookers have been proposed (for example, see Japanese Patent Application Laid-Open No. 10-42809).
However, it does not suggest, for example, an index corresponding to the collapse and hardness required for excellent rice balls or a quantitative range thereof.
In addition, a method of evaluating the hardness of rice cooked in a predetermined container (Japan Seminar on Cooked Foods, "Characteristics and Texture of New Aerated Cooked Rice", Norito Tatsumi (Ono Shokuhin Kogyo Co., Ltd.) April 28, 1998, Tokyo) is proposed, but a simple method that can be applied to cooked rice by directly measuring (in an open state that is not packed in a container) the molded rice itself and applying it to cooked rice. Is not found.

[0010]

The present invention has a moderate collapse.
There is no simple method for producing rice cooked such as rice balls or the like, and an objective index that can quantify the hardness or collapse of the rice is required.

It is an object of the present invention to mold rice (such as onigiri or nigiri sushi) (in the present invention, simply referred to as "molded rice"), and in particular, to form a moderately crumbled (hardness) molded rice cooked industrially. In particular, it is an object of the present invention to provide an index corresponding to a moderate collapse necessary for satisfying a moderate mash in a stage of carrying, grabbing into a mouth by hand, and a moderate mash, and a method of quantitatively obtaining the index. Based on this, it is easy to evaluate the collapse of the molded rice and industrially produce the molded rice having the target collapse.

[0012]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, the molded rice was subjected to a uniaxial compression rupture test using a rheometer to obtain a force-strain curve. We have found that there are two inflection points. Further, the first inflection point (referred to as "first inflection point") is a point at which the bonding between the cooked rice grains is weakened and the cooked rice blocks start to collapse,
The second inflection point (referred to as the "second inflection point") is the point at which the consolidation of the cooked rice grains starts after the collapse of the cooked rice, the force at the first inflection point is the breaking force, and the strain is the breaking strain. The measured value as is, the collapse of the molded cooked rice, is linked to the hardness, it can be used in the industrial production of molded cooked rice having the target collapse as an index to evaluate the collapse or to satisfy the appropriate collapse The present invention has been found that it can be used to evaluate and sort out the collapse of molded cooked rice, and based on these findings, the present invention has been completed.

[0013] That is, the present invention is a method for measuring the collapse of molded rice in which a molded rice is subjected to a uniaxial compression rupture test using a rheometer to measure a first inflection point of a force-strain curve.

Molded rice includes molded rice, for example, rice balls, nigiri sushi, inari sushi, cooked rice for lunches, etc., which are molded so as not to be destroyed by a certain force. Molded rice of the present invention is included as long as ingredients mixed with it are molded. Therefore, it includes cooked rice, and if it is formed, it is included in the formed cooked rice of the present invention.

Further, the present invention includes the following contents. [1] The molded cooked rice was subjected to a uniaxial compression rupture test using a rheometer to measure a first inflection point of a force-strain curve, and then created a stress-strain scatter diagram of the first inflection point. A method for examining the collapse of molded rice based on the value, or a method for examining or selecting the collapse of molded rice.

[2] At any stage of the process of manufacturing the cooked rice, the reference stress-strain scatter diagram having the target collapse at the first inflection point obtained by the above-described measuring method is adjusted. A method for producing molded cooked rice with controlled collapse.

[3] When the shaped rice is a rice ball, the reference stress-strain scatter diagram shows that the strain is 0.1 to 0.4 and the stress is 1
0-30 kPa range, more preferably strain 0.2-
The above manufacturing method, wherein the stress is in the range of 0.3 and the stress is in the range of 10 to 20 kPa.

[4] In the method for producing shaped rice described above,
Any of the preceding steps, wherein any stage of the manufacturing process is after the molding process, and / or after the molding-refrigeration process, and / or after the molding-freezing-thawing process.

[0019]

Next, an embodiment of the present invention will be described. Molded cooked rice is, as described above, a cooked cooked rice or a cooked cooked rice containing ingredients, which is manufactured by molding, refrigerated after molding, and frozen and thawed after molding. including. The first inflection point of the force-strain curve may be measured by performing a uniaxial compression rupture test using a rheometer. The relationship between the force (unit: N) and the strain (unit: none) may be measured by a conventional method using a plunger with the molded rice cooked directly on the rheometer. A measuring instrument capable of measuring the relationship is referred to as a rheometer in the present invention. still,
When the ingredients are present on the molded rice, the ingredients may be removed before measurement.

The obtained relationship, for example, the first rice ball
By finding inflection points and comparing them with each other, the degree of the collapse can be compared. For example, by comparing a plurality of obtained measurement values with each other or examining a numerical difference, it is possible to evaluate the collapse of the obtained molded cooked rice.
In addition to the relative comparison, it is also possible to obtain the value of a target first inflection point and absolutely evaluate this value and the hardness and collapse of the newly formed cooked rice.

On the other hand, the force at the first inflection point (unit:
It is also possible to compare the relationship between the value (stress, unit: kPa) obtained by dividing N) by the contact area between the plunger and the cooked rice and the strain (unit: none). This value is summarized in a stress-strain scatter diagram, and a scatter diagram of molded rice with a target collapse or a non-target scatter diagram is created, and by comparing with this, the target hardness, the molded rice with a collapse is obtained. Testing and sorting are possible. That is, the measurement method of the present invention is performed, and the obtained measurement value is obtained by at least one of the molded rice with the target collapse obtained by the measurement method obtained in advance.
By comparing the measured value with the measured value and / or the measured value of at least one of the molded rice having an unintended collapse, the collapse of the molded rice can be examined or selected.

Further, by comparing with the above scatter diagram,
Alternatively, by adjusting at the manufacturing stage so as to conform to this value, it is possible to industrially produce a molded rice having excellent collapse in large quantities. That is, the molded rice was subjected to a uniaxial compression rupture test using a rheometer to measure a first inflection point of a force-strain curve, and then a stress-strain scatter diagram of the first inflection point was created. By performing a test of the collapse of the molded rice based on the above, the collapse of the molded rice can be tested or selected.

At any stage in the process of manufacturing molded cooked rice, the collapse is adjusted to conform to the reference stress-strain scatter diagram at the first inflection point obtained by the measurement method of the present invention. This makes it possible to industrially produce broken rice. In this case, in advance, prepare a molded rice of the intended collapse, including the type of rice and the rice cooking conditions, determine the first inflection point of this molded rice, create a scatter diagram thereof, It can be manufactured so that the collapse of cooked rice is suitable.

In the case of cooked rice or nigiri sushi molded for a lunch box, the reference stress-strain scatter diagram preferably shows a strain of 0.
1 to 0.3 and a stress of 10 to 30 kPa, more preferably a strain of 0.2 to 0.25 and a stress of 13 to 20 kPa.
Range. At the time of eating rice or nigiri sushi molded for lunch, selection of raw rice to set this value, rice cooking conditions and the like are appropriately set, so that rice and nigiri sushi molded for a preferred lunch can be industrially manufactured. Can be manufactured.

In the case of rice balls, the reference stress-strain scatter diagram preferably shows a strain of 0.1 to 0.4 and a stress of 10 to 3
It is in the range of 0 kPa, more preferably in the range of 0.1 to 0.3 strain and 10 to 20 kPa stress. In the case of onigiri, a preferred onigiri can be industrially manufactured by referring to this value.

The value can be adjusted at any of the steps of producing rice, such as onigiri, and the like, and particularly at that step, after the molding step, after the molding-refrigeration step, or after the molding-freezing-thawing step. Preferably, there is. If there is a possibility of being sold and eaten immediately after molding, it may be adjusted after molding. After molding, it is stored frozen in a factory and thawed as necessary. When it is shipped, it is recommended to adjust it to fit the scatter diagram after thawing.

[0027] The molded rice thus produced has an appropriate adhesive strength, is preferably lysed, and is excellent in the binding power of rice.

[0028]

The present invention will be described below in detail with reference to examples.

[Method] 1-1. Sample Nipponbare (1997, Shiga Prefecture) was used. Each 10 kg of brown rice sample is a high barrier film (CANSFI
LM G-type, 100 μm × 350 mm × 540 mm, manufactured by Shikoku Kako Co., Ltd.), filled with nitrogen gas, sealed with a heat sealer and stored in a low-temperature storage at 4 ° C.

1-2. Rice cooker Rice cooker (SR-FY18, manufactured by Matsushita Electric Industrial Co., Ltd.), pressure / temperature controller, PC card type data collection system (NR-250, manufactured by KEYENCE CORPORATION), notebook personal computer (PC9801 nL / A) And a temperature / pressure control type rice cooker (manufactured by NN Sogo Denki Co., Ltd.) constituted by NEC Corporation. Rice 0.8k
The operation of washing g with 2 L of tap water was repeated three times, and the operation of sharpening with 2 L of tap water by an ordinary method was repeated five times. To the washed rice was added 1.12 kg of demineralized water so that the amount of water was 1.4 times the weight of the rice, and the rice was immersed at 25 ° C. for 60 minutes and then cooked.

When the rice cooking condition is expressed as a temperature control program for the heat transfer surface, the rice cooking conditions are 8 segments in total, and 1
The segment number is 23 ° C → 125 ° C for 5 minutes, the second segment is 125 ° C → 60 ° C for 15 minutes, the third segment is maintained at 60 ° C for 15 minutes, and the fourth segment is 60 minutes for 5 minutes.
° C → 170 ° C, 5th segment is kept at 170 ° C for 5 minutes, 6th segment is 170 ° C → 130 ° C in 5 minutes, 7
The segment number is 130 ° C. → 110 ° C. in 10 minutes, and the eighth segment is 110 ° C. → 50 ° C. in 55 minutes.

1-3. Molding of cooked rice In order to prevent the adhesion of cooked rice grains, an acrylic plate with a cooking sheet (Cook Par, made by Asahi Kasei Kogyo Co., Ltd.) affixed inside and covered with a wrap film for food packaging (Dia wrap, manufactured by Mitsubishi Aluminum Co., Ltd.) A self-made aluminum molding ring (inner diameter 45mm x H50m)
m, thickness of 5.0 mm) was filled with 50.0 g of cooked rice. Pressing lid (φ44m coaxial with a cylinder of φ55mm × H10mm)
mxH20mm cylinder joined shape, weight 0.142
5 kg) with a double-sided adhesive tape (No. 19, φ55 mm × H8 mm) and a maximum force of 1
A compression / tensile rheometer filled with a 9.6N load cell (creep meter RE-33005, manufactured by Yamaden Corporation)
And compression-molded at a compression speed of 1.0 mm · S ^-1 (corresponding to cooked rice for lunch). The formed cooked rice chunks were wrapped in a wrap film for food packaging, placed in a plastic sealed container, and released until the temperature reached room temperature. The cooking and preparation of the cooked rice block were performed in a constant temperature room at 25 ° C.

1-4. Freezing and thawing of cooked rice chunks Freezing was performed under two conditions: slow freezing (in-chamber temperature -15 ° C) and quick freezing (in-chamber temperature -35 ° C). For slow freezing, a refrigerator-freezer (341S1, manufactured by Daiwa Refrigeration Co., Ltd.) was used, and for rapid freezing, a low-temperature constant temperature and humidity machine (PL-1S, manufactured by Tabai Espec Co., Ltd.) was used.

For storage, the frozen rice chunks are stored at a temperature of -15
The test was carried out for 3, 7, 14, and 28 days in a refrigerator or a low-temperature thermo-hygrostat at −35 ° C.

Thawing is performed by natural thawing (still in a constant temperature room at 25 ° C.) and microwave thawing (sensor open grill range ER-EX55 (T), output 980 W, manufactured by Toshiba Corporation).
Under the two conditions. In the microwave thawing, one piece of cooked rice was placed at the center of the rotating table and thawed for 2 minutes in the mode of strong microwave oven.

1-5. Break test of cooked rice block A compression / tensile rheometer (creep meter RE-3300) equipped with a load cell having a maximum force of 19.6 N and a disk-shaped plunger (No. 19, φ55 mm × H8 mm).
5, Yamaden Corporation). (The contact area between the plunger and the cooked rice is 23.75 cm ² , and the value obtained by dividing the force (unit: N) by the contact area is the stress (unit:
kPa), and the same applies hereinafter. ) Compression speed
A uniaxial compression rupture test was performed at ⁰ mm · S ⁻¹ maximum strain 0.7 and data storage pitch (sampling speed) 0.1 s to measure the inflection point of the force-strain curve.

The breaking test was performed at a product temperature of 25 ° C. for the control system not subjected to the freeze-thaw treatment and the system naturally thawed, and at a product temperature of about 85 ° C. for the system thawed by microwave.

[Test Results] 2-1. Mechanical properties of cooked rice chunks (1) Control system In the control system which is not subjected to freezing / storage / thawing treatment, the strain in the force-strain curve is around 0.25 (around 8N) and around 0.55 (around 14N). Inflection points were observed in several places. The first inflection point (first inflection point) is a point at which the bonding between the rice grains weakens and the rice rice chunk starts to collapse, and the second inflection point (second inflection point)
The inflection point) was found to be the point where the cooked rice grains began to consolidate after the cooked rice block collapsed.

Therefore, it was found that by measuring the force at the first inflection point as the breaking force and the strain as the breaking strain, it is possible to evaluate the binding property between the cooked rice grains of the cooked rice block.

(2) Microwave thawing system The rice rice chunk is slowly frozen in a freezer refrigerator at a temperature of -15 ° C in the refrigerator, stored at -15 ° C for 3 to 28 days, and the force-deformation curve when microwave thawing is performed. Illustrated and created. According to this, in the rice rice block stored for 3 to 14 days, the distortion at the first inflection point was approximately equal to about 0.2, and the force was 3 to 4N.

On the other hand, when stored for 28 days, the strain at the first inflection point was reduced to about 0.15 and the force was reduced to 2N. From this, it was found that the binding property between the rice grains of the cooked rice chunk after storage for 14 days was weakened, and the cooked rice chunk tended to collapse.

The cooked rice chunk was rapidly frozen in a low-temperature constant temperature and humidity machine at a temperature of -35 ° C., stored at −35 ° C. for 3 to 28 days, and a force-deformation curve when microwave-thawed was obtained. According to this, the strain at the first inflection point existing in any of the force-deformation curves is about 0.2, but the stress decreases to 4N until 7 days of storage and about 3N after 14 days of storage. There was a tendency. From this, it is considered that the binding property between cooked rice tends to weaken as the storage period becomes longer.

In the case of onigiri, a similar tendency was observed when the test was carried out using the same freeze-thaw apparatus as described above. That is, rice balls produced by a rice ball molding machine (no freezing and thawing treatment), stress of 12.1-15.5 k
The following freezing using a strain of 0.27 to 0.33 at Pa
Microwave thawing was tested (note: this rice ball shows a similar value to the first inflection point of the commercially available rice ball). As a result, slow-frozen (−15 ° C.) 14 or 28
After storing for 14 days, the product was thawed in a microwave oven (sensor oven grill range ER-EX55 (T), output 980 W, manufactured by Toshiba Corporation), and the product stored for 14 days was stressed at 5.18 to 6.90 kPa with no strain. Those stored for .20 and 28 days reduced the strain to 0.15 at a stress of 3.45 kPa. On the other hand, after quick-frozen (-35 ° C.) was stored for 7 or 14 days and then thawed in a microwave oven,
Those stored for a day have a stress of 6.90 kPa and a strain of 0.2
Those stored for 0 and 14 days reduced the strain to 0.20 at a stress of 5.18 kPa, but showed better results compared to slow freezing.

Therefore, in the case of producing a frozen molded rice having a long freezing storage period, it is desirable that the molded rice in the production stage before freezing be produced in advance as a molded rice having a large stress. In addition, when it is unavoidable to freeze slowly due to the presence or absence of manufacturing equipment, it is necessary to produce molded rice having a different stress from rapid freezing when producing molded rice before freezing. It is possible to manufacture molded rice that is preferably set quantitatively based on the strain scatter diagram and the production process is preferably controlled.

(3) Natural thawing system Rice chunks are slowly frozen in a refrigerator at a temperature of -15 ° C., stored at -15 ° C. for 14 days, and then left in a constant temperature room at 25 ° C. for natural thawing or A typical force-deformation curve for microwave thaw was determined. According to this, both showed completely different curves. That is, when naturally thawed, the first inflection point (strain about 0.2, force about 16 N) is the yield point of the stress-deformation curve, and the control system not subjected to the freezing / storage / thawing treatment is used. Was significantly different from the force-deformation curve obtained in the above.

On the other hand, when the microwave is thawed, the first
The inflection point (strain about 0.25, force about 7N) was not the yield point of the force-deformation curve and resembled the curve of the control system.
Therefore, it was decided to pay attention only to the first inflection point in the rice rice chunks naturally thawed.

FIG. 1 shows a stress-strain scatter diagram in the case of slow freezing.
FIG. 2 shows the rapidly frozen product. With slow freezing, there was a category for each storage period in the stress-strain scatterplot. That is, in the system stored for 3 days, the strain at the first inflection point at which the rice block starts to collapse is almost constant at 0.18, but the stress is distributed at 10 to 20 kPa, and the adhesion of rice grains of the rice block is It was found that there were individual differences in gender of the samples. In the system stored for 7 days, there were two regions having a stress of 14 to 16 kPa and a strain of 0.18 to 0.22, and two regions of a stress of 10 to 13 kPa and a strain of 0.23 to 0.26. 1
In the system stored for 4 days, the distribution of strain was wide such that the stress was 9 to 13 kPa and the strain was 0.19 to 0.27. In the system stored for 28 days, the stress is 13 to 19 kPa.
And the first inflection point was concentrated and distributed such that the distortion was 0.18 to 0.22.

On the other hand, in the case of rapid freezing, the stress and strain at the first inflection point do not form a category for each storage period as in the case of slow freezing.
The strain was in the range of 0.19 to 0.26.

Evaluation of the degree of collapse of cooked rice for lunches Based on the above scatter diagram, the relationship between the range having a moderate level of collapse, which is excellent in terms of adhesive strength, melting, and binding strength, was evaluated by a panelist for sensory evaluation. Was evaluated.

The stress-strain scatter diagram preferably shows a strain of 0.
1 to 0.3 and a stress of 10 to 30 kPa, more preferably a strain of 0.2 to 0.25 and a stress of 13 to 20 kPa.
Was found to be in the range. Therefore, when cooked rice cooked for a lunch box is similarly industrially manufactured, the first inflection point is adjusted based on this preferable scatter diagram, and molding (freezing and thawing as necessary) results in an adhesive strength. It was possible to produce cooked rice for a lunch box having a moderate collapse that is excellent in terms of mashing and binding power.

In the case of nigiri sushi, the test was repeated in the same manner as described above, followed by freezing and thawing after molding, similarly obtaining the first inflection point, and similarly obtaining the intended stress-strain scatter diagram.
Based on this, the desired Nigiri sushi, that is, Nigiri sushi having a moderate collapse which is excellent in terms of adhesive strength, melting and binding power, could be industrially produced in large quantities.

Further, in the case of rice balls, the test was repeated in the same manner as described above, and after freezing and thawing after molding, the first inflection point was obtained in the same manner, and the desired stress-strain scatter diagram was obtained. In the case of rice balls, the stress-strain scatter diagram preferably shows a strain in the range of 0.1 to 0.4 and a stress of 10 to 30 kPa, more preferably a strain of 0.1 to 0.3 and a stress of 10 to 20 kP.
The range of a was obtained. Based on this, the desired onigiri, that is, onigiri excellent in terms of adhesive strength, binding strength, etc., could be industrially produced in large quantities.

[0053]

According to the present invention, it has been found that a molded rice has a first inflection point. The molded rice is subjected to a compression rupture test using a rheometer, and the first inflection point obtained is a point at which the binding between the rice grains weakens and the rice mass starts to collapse,
It was also found that the measured value obtained by measuring the force at the first inflection point as a breaking force and the strain as a breaking strain was linked to the collapse and hardness of the molded cooked rice, and this was used as an index indicating a moderate collapse. By doing so, or by comparing the numerical values, the collapse of the molded rice can be tested, selected, and evaluated, and the molded rice having the intended collapse can be industrially produced. Of course, the present invention is also useful from the viewpoint of preventing broken cooked rice from occurring during movement of the manufacturing process line.

The intended collapse of the molded rice is determined by selecting the raw rice, cooking rice, and production conditions (whether the rice may be eaten immediately after molding, may be frozen and thawed after molding, and then subjected to distribution,
Depending on the conditions of freezing and thawing, etc.) and the type of cooked rice (rice ball, sushi or lunch box, etc.), the desired degree of collapse varies, so consider the degree of collapse appropriate for each in advance. For example, by preparing a stress-strain scatter diagram, comparing with the scatter diagram, and making necessary adjustments, it is possible to industrially produce and supply molded cooked rice having a target collapse.

[Brief description of the drawings]

FIG. 1 shows a stress-strain scatter diagram when slowly frozen in an example. Sample frozen at -15 ° C, 3 at -15 ° C
-Store for 28 days and thaw at 25 ° C. ◆: stored for 3 days; Δ: stored for 7 days; Δ: stored for 14 days;
X: Storage for 28 days.

FIG. 2 shows a stress-strain scatter diagram in the case of rapid freezing in an example. Sample frozen at -35 ° C, 3 at -35 ° C
-Store for 28 days and thaw at 25 ° C. ◆: Storage for 14 days; Δ: Storage for 28 days; X: Storage for 7 days; *: Storage for 3 days.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tsutomu Harada 1-1 Fukui term, Ajinomoto Co., Ltd. Food Research Institute 1-1, Suzukicho, Kawasaki-ku, Kawasaki City, Kanagawa Prefecture 2G061 AA02 AB03 CA11 CA18 CB00 EA01 EA04 EB05

Claims (6)

[Claims] 1. A method for measuring the collapse of molded rice, comprising subjecting the molded rice to a uniaxial compression rupture test using a rheometer and measuring a first inflection point of a force-strain curve. 2. A molded rice cooker is subjected to a uniaxial compression rupture test using a rheometer to measure a first inflection point of a force-strain curve, and then a stress-strain scatter diagram of the first inflection point is created. And a method for determining the collapse of the molded rice, or selecting the rice based on this value. 3. A reference stress-strain scatter diagram having a target collapse at a first inflection point obtained by the measuring method according to claim 1 at any stage of the process of manufacturing molded cooked rice. Characterized in that the collapse is adjusted as described above. 4. The method according to claim 3, wherein the molded rice is an onigiri. 5. The reference stress-strain scatter diagram has a strain of 0.1
5. The method according to claim 4, wherein the stress is in the range of 0.4 to 0.4 and the stress is in the range of 10 to 30 kPa. 6. The method according to claim 3, wherein any one of the steps of the production step is after the molding step, after the molding-refrigeration step, or after the molding-freezing-thawing step.