JPH0789879B2 - A safe and long-term storable rice production method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing cooked rice that can be stored for a long period of time. More specifically, the present invention relates to a method for producing cooked rice that does not cause binding or crushing of rice grains during the production process and distribution stage and can maintain the freshly cooked taste and aroma even after long-term storage.

[0002]

2. Description of the Related Art With respect to cooked rice, various types of retort cooked rice that can be cooked in a short time by simple means and cooked rice produced by an aseptic manufacturing method are on the market. There are many known methods for producing retort cooked rice.
For example, a bag of synthetic resin film or the like is filled with rice cooked in hot water for 2 to 10 minutes, sealed, and sterilized under pressure to produce cooked rice (Japanese Patent Publication No. 57-43222).
A method of producing retort cooked rice with smooth rice grain surface and less stickiness by placing washed rice with water as uniformly as possible in a bag (Japanese Patent Laid-Open No. 62-51959), and filling rice in the retort pouch after cooking rice. A method of sealing and sterilizing under pressure (Japanese Patent Laid-Open No. 56-72655) is known.

However, since these retort cooked rice is subjected to high-temperature heat treatment (for example, heated at 120 ° C. for 20 to 30 minutes), the taste and aroma of freshly cooked rice cannot be maintained, and the binding and crushing of rice grains at the manufacturing process and distribution stage. Occurs, which impairs the appearance and texture, and does not have the freshly cooked flavor and texture to taste at home.

Further, a conventional aseptic manufacturing method in which normal pressure cooked rice or cooked cooked rice is filled with a deoxidizer in a heat resistant container having a barrier property in an aseptic facility and the container is completely sealed (for example, JP-A-3-133348). Japanese Laid-Open Patent Publication No. 3-985
The instant cooked rice produced in accordance with Japanese Patent No. 42) has a scent and taste superior to that of the retort cooked rice in the case of normal pressure cooked rice, but there is a food hygiene problem as the cooked rice for storage, and In the case of pressure cooked rice, since it is cooked in a temperature range of about 105 ° C. to 120 ° C., there are problems that the taste and aroma of freshly cooked rice cannot be maintained and that rice grains are bound and crushed.

In the conventional aseptic manufacturing method for cooking rice under normal pressure, the steps after heating (about 100 ° C.) for cooking rice are carried out in an aseptic facility to prevent bacterial contamination of cooked rice and to remove oxygen scavenger. In order to prevent the aerobic bacteria and fungi from growing by making the oxygen concentration in the container 0.1% or less by encapsulating, the need for high temperature and high pressure retort sterilization is eliminated. However, when the polished rice was contaminated with anaerobic food poisoning bacteria such as Clostridium botulinum from the beginning, these bacteria were not completely killed by the heat treatment during cooking (about 100 ° C.), and the oxygen concentration was 0.1. Since it proliferates in cooked rice in a container of less than 100%, safety as a preserved food becomes a problem. Food poisoning caused by Clostridium botulinum develops when food poisoning bacteria grow in food and produce a specific toxin, and the symptoms show specific neurological symptoms with a fatality rate of 30 to 60%. It is the most feared food poisoning that spreads.

Further, a method for processing ready-to-cook rice by washing polished rice, sterilizing it with ultraviolet rays, microwaves, or ozone until it becomes aseptic and packing it in a sterile bag under vacuum (Japanese Patent Application Laid-Open No. Sho-6). 61-5750) is known. However, in reality, it is difficult to completely sterilize the bacteria contaminated with rice by any of the methods.

[0007]

[PROBLEMS TO BE SOLVED BY THE INVENTION] A method for producing cooked rice is provided which does not cause binding or crushing of rice grains and which can maintain the freshly cooked taste and aroma even after being stored at room temperature for about 6 months or longer. .

[0008]

Means for Solving the Problems As a result of intensive studies in view of the above problems, the present inventors have found that gluconodeltalactone,
Alternatively, using dipping water or cooking water containing an edible organic acid such as citric acid, tartaric acid, malic acid, fumaric acid, succinic acid, gluconic acid, lactic acid, acetic acid, adipic acid, phytic acid, ascorbic acid or a salt thereof, PH of cooked rice after cooking
Is adjusted to be a specific value, and cooked cooked rice is filled with a deoxidizer in a container in a sterile facility, and it is found that the problem can be solved by completely sealing the present invention. I arrived.

According to the first aspect of the present invention, the polished rice is washed, then immersed in immersion water, then taken out of the immersion water, and the cooking water is added just before the rice is cooked. In a method for producing cooked rice that is filled with a deoxidizer in a heat-resistant container and completely sealed, it contains at least one selected from glucono delta lactone, gluconic acid and salts thereof, or a mixture thereof as an essential component.
3. The pH of cooked rice after cooking with immersion water and cooking water is 4.
A method for producing a safe and long-term storable cooked rice, which comprises adjusting the concentration to be 0 to 4.8 and preventing the growth of food poisoning bacteria such as botulinum.

The invention of claim 2 of the present invention is citric acid, liquor
Tartaric acid, malic acid, fumaric acid, succinic acid, lactic acid, acetic acid,
Dipic acid, phytic acid, ascorbic acid and its salts
At least one selected from these mixtures
Immersion water and / or cooking further containing edible organic acid
The method for producing cooked rice which is safe and can be stored for a long time according to claim 1, wherein water is used .

[0011] The invention of claim 3 of the present invention, or the claims 1, wherein the salt is potassium salt, sodium salt, calcium salt and salts of at least one organic acid selected from mixtures thereof Safety according to claim 2
And a method for producing a shelf-stable rice.

The polished rice used in the present invention is a refined product such as non-glutinous rice, glutinous rice, wild rice and brown rice. If necessary, semi-cooked and semi-heated products such as pregelatinized rice and other grains may be added.

In the present invention, milled rice is washed by a conventional method. After washing the polished rice, it is immersed in immersion water. Usually, the water content of raw rice is 10 to 18%, so it is known to immerse it in water or spray it with water so that the water content of milled rice is about 20 to 50%. However, it is not limited to this range. Remove the polished rice from the immersion water, and then add 1.0 to 1.5 times the amount of cooking water to the rice immediately before cooking rice, and cook the rice under normal pressure using a heat source such as gas, electricity, or steam according to the usual method. I do.

After the rice has been cooked in this manner, it is filled with a deoxidizer in a barrier heat-resistant container in a sterile facility while the rice is relatively warm, at about 60 ° C. or higher, and completely sealed by, for example, a heat-sealing machine. . For example, the United States Aerospace Agency (NA
Aseptic filling is performed in a clean room or clean booth of class 100 to class 10000 according to the SA standard.
When performing aseptic filling, use fully sterilized equipment, packaging materials, containers, oxygen absorbers, etc.

A preferred gas barrier heat resistant container package is a tray container made of heat resistant synthetic resin or a plastic bag made of a laminated material of heat resistant synthetic resin film and / or metal foil. For example, for the tray container, a vinylidene chloride film is used as an intermediate layer, and upper and lower layers are formed by laminating polypropylene and molded into a tray shape, and a tray container upper lid film (PET / K nylon / polyethylene sealant) can be used. .

In the method for producing cooked rice as described above, in the present invention, the pH of cooked rice after cooking is 4 using immersion water and / or cooking water containing gluconodeltalactone, an edible organic acid or a salt thereof. It is necessary to adjust so as to be 0.0 to 4.8 in order to produce cooked rice that can maintain the taste and aroma of freshly cooked food even after long-term storage.

Gluconodelta lactone used in the present invention is a food additive and can be preferably used in the present invention. The above-mentioned edible organic acid used in the present invention is an edible acid recognized as a food additive, for example, citric acid, tartaric acid, malic acid, fumaric acid, succinic acid, gluconic acid, lactic acid, acetic acid, adipic acid, phytic acid. , Ascorbic acid, or a mixture thereof, and citric acid, gluconic acid, or a mixture thereof can be preferably used in order to satisfy both long-term storage stability and taste. Examples of the salt of the edible organic acid used in the present invention include potassium salt, sodium salt, calcium salt, and a mixture thereof.
Also, a mixture of glucono delta lactone and these edible organic acids or salts thereof can be used.

The pH of cooked rice cooked without the use of edible organic acids is about 6.7. This cooked rice has an excellent taste but is inferior in long-term storability. It was clarified that it is possible to prevent the growth of food poisoning bacteria by adjusting the pH of the cooked rice to be 4.0 to 4.8. The lower the pH value is adjusted, the higher the effect of preventing food poisoning bacteria from growing, but it is not desirable because it adversely affects the taste. Conversely, if the pH value is adjusted to a high value, the long-term storage stability deteriorates, so commercialization as a long-term storage food In order to achieve this, the pH of cooked rice after cooking should be 4.0 to 4.0, considering that it needs to be stored at room temperature for at least about 6 months.
It has been found that it is preferable to control to 4.8.

In the present invention, a specific method for adding glucono delta lactone, edible organic acid or the like to immersion water or cooking water to produce cooked rice having a pH value within the above range is polished rice. After washing rice, soaking it in water for a certain period of time, immediately before cooking rice, add glucono delta lactone or edible organic acid or its salt to the cooked water and cook the rice, after washing polished rice, glucono delta lactone or edible organic acid Alternatively, immerse in a solution containing the salt for a certain period of time, and
Decrease the value and cook the rice as it is, wash the polished rice and then soak it in a solution containing glucono delta lactone, edible organic acid or its salt for a certain period of time
There is a method of cooking by adding glucono delta lactone or an edible organic acid or its salt to the cooking water immediately before cooking rice, but from the viewpoint of stability and quality of final pH value, the method of Is the most realistic and preferred method.

The sterile-filled cooked rice prepared as described above is
It can be reheated in a microwave oven or a heated water bath and served.

In the present invention, seasonings, colorants, fats and oils, emulsifiers and the like may be further added to cooked rice and water without departing from the spirit of the present invention.

[0022]

In the present invention, gluconodeltalactone,
Alternatively, using cooked water or immersion water containing an edible organic acid such as citric acid or gluconic acid, or salt thereof, the cooked rice is cooked by controlling the pH of the cooked rice after normal pressure cooking to 4.0 to 4.8. By filling the gas barrier heat-resistant container with the oxygen scavenger in an aseptic facility and completely sealing it, the growth and activity of aerobic bacteria and anaerobic bacteria can be suppressed without binding or crushing of rice grains. Therefore, it is possible to provide cooked rice excellent in long-term storability such that the taste and aroma of freshly cooked food can be maintained even after long-term storage.

[0023]

EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited to these examples without departing from the gist of the present invention. (Effect of glucono delta lactone and each edible organic acid on the taste of cooked rice) Polished rice is kept in an aqueous solution containing glucono delta lactone and each edible organic acid for a certain time (60 to 90 minutes)
The pH was lowered by immersing the mixture, and the edible organic acid was added to the cooked water immediately before the rice was cooked, so that the pH of the cooked rice after cooking was 4.5 and 5.5, as shown in (Table 1) below. Cooked rice was prepared by cooking under the cooking conditions, and the effects of gluconodeltalactone and each edible organic acid on the taste of cooked rice were investigated.
The pH was measured by the following method. To 20 g of cooked rice, add 50 cc of distilled water and treat with a homogenizer. After standing for 5 minutes, the pH is measured with a pH meter [HM-30S manufactured by Toa Denpa Kogyo KK]. The taste of cooked rice was sensory evaluated by a trained taste judge, and the results are summarized in Table 2.

[0024]

[Table 1]

[0025]

[Table 2]

From the above results, the above-mentioned additions are effective additives that can be used in the method for producing a long-term storable cooked rice of the present invention while minimizing the decrease in the commercial value of the cooked rice due to the sourness and the like. Any of the agents can be used, but as glucono delta lactone and edible organic acid, citric acid,
It turns out that gluconic acid and combinations thereof are preferred.

(Change in pH of Rice with Time when the Polished Rice is Soaked in Citric Acid Aqueous Solution of Various Concentrations) Polished Rice 10 k
After washing g of rice, the change in pH of rice when immersed in 25 liters of an aqueous citric acid solution of various concentrations (citric acid concentration of 0.05% by weight, 0.20% by weight, 0.50% by weight) at room temperature was examined. The results are summarized in Fig. 1.

(Examples 1 to 5, Comparative Examples 1 to 5) Water content 1
After washing 5% of the above polished rice, water is used as the immersion water or an immersion aqueous solution containing glucono delta lactone and various edible organic acids is added and immersed for 60 minutes to a water content of 32%, immediately before cooking rice. Boiled rice was produced by controlling the pH value of the cooked rice under the above-mentioned cooking conditions, using water as cooking water or using cooking water to which gluconodeltalactone and various edible organic acids were added. With the rice cooked at about 60 ° C, a dry laminated material consisting of PP / EVOH / PP was made into a bag as a barrier heat-resistant container in a class 100 bioclean room, and some parts were not heat-sealed and not welded. Using a plastic bag provided with a part, it was filled with an oxygen scavenger and heat-sealed by a heat-sealing machine to completely seal it.

After this was stored at room temperature for about 6 months, it was warmed and eaten in a microwave oven for 3 minutes to evaluate the taste and storability of cooked rice. In each of the examples and the comparative examples, when cooked for 3 minutes in a microwave oven, white cooked rice with a fluffy and voluminous color was obtained, and no binding or crushing of rice grains occurred. The results are summarized (Table 3).

[0030]

[Table 3]

(Example 1) This is a case where water is used as the immersion water and cooking water containing glucono delta lactone is used. After storing at room temperature for about 6 months, the rice cooked in a microwave oven for 3 minutes had no off-taste, had a faint sour taste, and had a fresh texture.

(Example 2) This is a case where an immersion aqueous solution containing gluconic acid was used as the immersion water and the water was used as cooking water. After storing at room temperature for about 6 months, the rice cooked in a microwave oven for 3 minutes had no off-taste, had a faint sour taste, and had a fresh texture.

(Example 3) This is a case where an immersion aqueous solution containing citric acid was used as the immersion water, and the water was used as cooking water. Store at room temperature for about 6 months and then microwave for 3 months.
The cooked rice warmed for a minute had no offensive odor, had a mild sourness, and had a fresh texture.

(Example 4) This is a case where an immersion aqueous solution containing citric acid was used as the immersion water and an aqueous solution containing gluconic acid was used as the cooking water. After being stored at room temperature for about 6 months, the cooked rice was warmed in a microwave oven for 3 minutes, had no offensive odor, had a mild sourness, and had a fresh texture.

(Example 5) This is a case where an immersion aqueous solution containing gluconodeltalactone was used as the immersion water and an aqueous solution containing gluconic acid was used as the cooking water. After being stored at room temperature for about 6 months, the rice cooked in a microwave for 3 minutes has no offensive odor and has a slightly sour taste.
It had a fresh texture.

(Comparative Example 1) This is a case where an immersion aqueous solution containing citric acid was used as the immersion water and an aqueous solution containing gluconic acid was used as the cooking water. Since the pH after cooking rice is higher than the pH range of the present invention, there is a problem in storability (there is a risk of toxin production by food poisoning bacteria), and those stored at room temperature for about 6 months are not suitable for sensory tests. .

Comparative Example 2 This is a case where an immersion aqueous solution containing gluconodeltalactone was used as the immersion water and an aqueous solution containing gluconic acid was used as the cooking water. Since the pH after cooking rice is smaller than the pH range of the present invention, after being stored at room temperature for about 6 months, the rice cooked in a microwave oven for 3 minutes has no off-flavor and odor and is excellent in storability, but has a sour taste. And there was no fresh texture.

(Comparative Examples 3 to 5) Immersion aqueous solutions containing lactic acid (Comparative Example 3), acetic acid (Comparative Example 4) and malic acid (Comparative Example 5) were used as the immersion water, and water was used as cooking water. This is the case. After being stored at room temperature for about 6 months, the rice cooked in a microwave for 3 minutes has no off-flavor and has an excellent storability, but has an astringent sourness (Comparative Example 3), which has a stimulating sourness. There was no fresh texture due to certain (Comparative Example 4), bitter and sour taste (Comparative Example 5), and the like.

(Examples 6 to 8 and Comparative Examples 6 to 7) As described below, the polished rice was botulinum (Closto) before being cooked.
ridium Botulinum) was contaminated with rice, then cooked, filled, sealed and stored for long-term storability testing (effect of initial contamination). When making cooked rice using the above polished rice according to the method of Example 3, botulinum bacteria were inoculated so that 10 ⁴ cells per 1 g of soaked rice were cooked, and then cooked to give a class 100.
In a clean room, the gas barrier packaging material was aseptically filled. In addition, an oxygen scavenger is enclosed and sealed in an anaerobic state and stored in a constant temperature bath at 30 ° C for 1, 3, 6, 9, 12
The presence or absence of toxin was determined after a month. In addition, the presence or absence of toxin was determined by the following determination method by administration to mice. Add and mix 100 cc of sterilized water to 50 g of cooked rice,
Leave for hours. After 20 seconds of stomaching with a stomacher, the supernatant is aseptically collected, left for 1 hour, and then treated with a centrifuge (3000 rpm × 40 minutes). The supernatant is collected aseptically, left in hot water at 37 ° C for 10 minutes, then stored in a thermostat at 35 ° C for 40 minutes, and then left at room temperature. 0.4 ml is collected and intraperitoneally injected into the mouse (5 animals per sample). After that, the animals were bred by a conventional method, and one of the five animals that died was (+), and the one that survived in total was (-). The results are summarized (Table 4).

[0040]

[Table 4] The control is the case of cooked rice made without using glucono delta lactone or edible organic acid. It is understood that this cooked rice has excellent flavor and taste, but has poor long-term storage stability. It is understood that it is possible to prevent the growth of food poisoning bacteria by adjusting the pH of cooked rice to be 4.0 to 4.8.

(Examples 9 to 11 and Comparative Examples 8 to 9) When cooked rice was prepared using the above-mentioned polished rice according to the method of Example 3, cooked rice was cooked with the above food poisoning bacteria as follows. Long-term storability was tested by contaminated filling, sealing, and storage (effect of secondary contamination during filling). Example 3 using the above polished rice
When making cooked rice according to the method of 1., cook the soaked rice, aseptically fill the gas barrier packaging material in a class 100 clean room, and at the same time put the oxygen absorber into the anaerobic state, then botulinum Inoculate with 10 ³ bacteria per 1 g of cooked rice, seal, and store in a constant temperature bath at 30 ° C.
The presence or absence of toxin was determined after 3, 6, 9 and 12 months. The presence or absence of the toxin depends on the method of administration to mice. Similar to the test for the effect of initial contamination, one that died in the sample was (+), and one in which all five were alive was (-).
The results are summarized (Table 5).

[0042]

[Table 5] The control is the case of cooked rice made without using glucono delta lactone or edible organic acid. It can be seen that this cooked rice has excellent flavor and taste, but poor long-term storage stability.
It is understood that it is possible to prevent the growth of food poisoning bacteria by adjusting the pH of cooked rice to be 4.0 to 4.8. (Examples 12 to 14) After washing polished rice, the average pH of cooked rice is 4.5, 4.
4 and 4.3 so that the pH is lowered to some extent by immersing in a solution containing glucono delta lactone, an edible organic acid or a salt thereof and having a pH shown in Table 6 for a certain period of time. Rice was cooked using cooking water having a pH shown in Table 6 to which delta lactone, an edible organic acid or a salt thereof was added. Then, the pH of the following cooked rice was measured. The results are shown in Table 6. A total of 5 points were sampled from the four corners and the center of the upper surface of the rice cooker having a rectangular parallelepiped shape, one from the center of the middle part, and five from the four corners and the center of the bottom to make a pH measurement sample. (Comparative Examples 10 to 12) After washing polished rice and immersing it in tap water for a certain period of time, gluco was prepared immediately before cooking so that the average value of pH of the cooked rice was 4.5, 4.4 and 4.3. Rice was cooked using cooking water having a pH shown in Table 6 to which nodeltalactone, an edible organic acid or a salt thereof was added. And pH of the cooked rice was measured like Example 12-14. The results are summarized in Table 6. (Comparative Examples 13 to 15) After washing polished rice, the average pH of cooked rice is 4.5, 4.
Immediately before cooking rice, it is immersed in a solution containing glucono delta lactone or an edible organic acid or its salt for a certain period of time to reduce the pH to 4 and 4.3, and then cooked with tap water (cooking water). did. And pH of the cooked rice was measured like Example 12-14. The results are summarized in Table 6.

[Table 6] From the results of Table 6, in the case of Examples 12 to 14, the difference between the maximum value and the minimum value (pH range) of the cooked rice is 0.5 or less, so the average value of pH is 4.3 to 4. When adjusted to be 5, the pH range of the cooked rice of the present invention is easily 4.0 to 4.8.
Can be On the other hand, in Comparative Examples 10 to 12, the difference (pH range) between the maximum value and the minimum value of the cooked rice is 0.8 or more, so that the pH range of the cooked rice of the present invention is 4.
There is a risk of deviating from 0 to 4.8 and there is a problem in safety. In Comparative Examples 13 to 15, since the difference (pH range) between the maximum value and the minimum value of cooked rice is 0.7 or more, the pH range of cooked rice of the present invention is set to 4.0 to 4.8. There is a risk of deviation and there is a safety issue. In any case, the pH can be adjusted by stirring or prolonging the immersion time.
However, the rice is heavy and difficult to stir, and vigorous stirring causes the particles of the rice to collapse and the finish to deteriorate. Then, the starch quality of rice leaks out, which causes stickiness and kogation, which is not an effective means because it takes time and labor. Since the pH of cooked rice changes by about ± 0.1 depending on the quality of the raw rice,
From the viewpoint of safety, it is preferable to adjust the pH of cooked rice by the method of Examples 12 to 14.

[0043]

Industrial Applicability As described above, after washing polished rice, soaking it in immersion water, taking it out of the immersion water, adding the cooking water immediately before cooking rice, and cooking the rice, and then in a gas barrier heat-resistant container in a sterile facility. When producing cooked rice which is filled with deoxidizer and completely sealed, the pH of cooked rice after cooking is adjusted by using immersion water or cooking water containing glucono delta lactone, edible organic acid or its salt. The rice cooked by the manufacturing method of the present invention has a long-term shelf life of about 6 months or longer when stored at room temperature, and at the same time, the grain size of the rice grains is adjusted in the manufacturing process and distribution stage. It does not cause wearing or crushing, has no offensive odor even after long-term storage, and has an excellent texture. Furthermore, cooked cooked rice can be reheated and eaten in a microwave oven or hot water for 2 to 20 minutes, which can save labor in heating and cooking equipment in fast food chains, convenience stores, etc. The utility value above is enormous.

[Brief description of drawings]

FIG. 1 is a graph showing changes in pH of rice with time when polished rice is immersed in an aqueous citric acid solution having various concentrations.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihiro Kazama 38-8 Miyamoto-cho, Itabashi-ku, Tokyo Esubie Foods Co., Ltd. Central Research Institute (72) Inventor Tomohide Muta 38-8 Miyamoto-cho, Itabashi-ku, Tokyo Esubie Foods Co., Ltd. Inside Central Research Laboratory (72) Inventor Soichi Shiiya 38-8 Miyamoto-cho, Itabashi-ku, Tokyo Esu Foods Co., Ltd. Central Research Laboratory (56) Reference JP-A-2-128663 (JP, A) JP-A-59-88053 ( JP, A) JP 3-87152 (JP, A) JP 60-172262 (JP, A) JP 53-12438 (JP, A) JP 63-248353 (JP, A)

Claims (3)

[Claims] 1. Washing polished rice, immersing it in immersion water, then taking it out of the immersion water, adding the cooking water just before cooking rice and cooking the rice, and then deoxidizing it in a gas barrier shochu container in a sterile facility. In the method for producing cooked rice, which is filled together with and completely sealed, cooked rice using immersion water and cooking water containing at least one selected from gluconodeltalactone, gluconic acid and salts thereof or mixtures thereof as essential ingredients. A method for producing safe and long-term storable rice, which comprises adjusting the pH of the later cooked rice to be 4.0 to 4.8 and preventing the growth of food poisoning bacteria such as botulinum bacteria. 2. Citric acid, tartaric acid, malic acid, fumaric acid, succinic acid, lactic acid, acetic acid, adipic acid, phytic acid,
The safe and long-term storable cooked rice according to claim 1, wherein immersion water and / or cooking water further containing at least one edible organic acid selected from ascorbic acid and salts thereof or a mixture thereof are used. Manufacturing method. 3. The safe according to claim 1 or 2, characterized in that the salt is a salt of at least one organic acid selected from potassium salt, sodium salt, calcium salt and mixtures thereof. A method for producing cooked rice that can be stored for a long period of time.