JPH09117260A - Preparation of packaged rice not rinsed but storage over long period - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject product produced by the rice-washing step, pressurized water treatment step, gelatinization and drying step, disinfection step, etc., by respective specific methods, free from the body breakage of the rice grain, having excellent palatability and preservability and dispensing with the temperature control in distribution stage. SOLUTION: Refined rice grains are vibrated with an ultrasonic vibration plate to remove the powder from the surface of the rice. The rice subjected to the above polishing treatment is added with water, washed by an ultrasonic vibration plate to remove the powdery component and dried to a water content of 10-15%. The dried rice is exposed to a pressurized water of 5-20atm to increase the water content to 40-45% and dehydrated to a water content of 30%. The dehydrated rice is gelatinized and dried by a far infrared drier to a water content of 23-25% and sterilized by ultraviolet irradiation. The sterilized rice is packed in vacuum. Preferably, a deoxidation agent is sealed together with the rice in the vacuum packaging to prevent the oxidative degradation, etc., of the rice.

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 unwashed rice without packaging, and more particularly to a method for producing unwashed rice that can be stored for a long period of time.

[0002]

2. Description of the Related Art Conventionally, as a method for producing this type of packaged unwashed rice, the washed rice is immersed in water for a short period of time to adjust the water content of the washed rice, and this is boiled for a short time to make the surface alpha and then dried. Alternatively, the raw rice soaked in water, if necessary, was covered with starch or a pasty liquid in which rice flour was dispersed in water, and then packed in a container and vacuum-packed to hermetically package.
In such a manufacturing method, in the former case, the water content is reduced by drying, so that the elasticity is lost, the body cracks, the texture is inferior, and the gloss is poor. Further, in the latter case, there is a problem that a paste-like liquid such as starch has to be prepared separately, and the manufacturing process is complicated and the apparatus becomes large-scale.

Therefore, for the purpose of solving such a problem, in JP-A-2-265448, water is further added to the grain surface of white rice which is humidified to have a water content of 14.5% or more after rice polishing. At the same time, there is disclosed a method for processing non-washed rice in which hot air of 75 ° C. or higher is supplied for a short time to gelatinize only the surface layer portion of the white rice grains while the added water does not permeate into the inner layer portion of the white rice grains. Further, Japanese Patent Laid-Open No. 3-27260 discloses that
Washing the polished rice by contacting it with cold water at a temperature of 20 ° C or lower for 5 minutes or less, and 0.5 times by weight or more of washed rice with ethanol at a temperature of 20 ° C or lower for about 30 seconds to 10 minutes. Disclosed is a method for producing non-washed rice, which comprises a step of contacting the washed rice and a step of drying the washed rice under low vacuum conditions.

[0004]

In the method for processing unwashed rice or the method for producing unwashed rice described in the above-mentioned prior art, unless the degree of rice polishing is increased, the adhesion of bran and bran oil cannot be avoided, and the bran and bran oil When the rice is cooked with the sticking to it, there is a problem that the color of the cooked rice has a yellowish tinge, and the rice has a bran odor and only the rice with poor palatability can be obtained.

Since the number of bacteria attached to raw rice is large, the high moisture content rice that has been washed and soaked in water requires temperature control at the distribution stage, is easy to eat, and has a shelf life of about 30 days. However, there is a problem that it cannot be said that the shelf life is long enough.

Therefore, for the purpose of solving such a problem, in Japanese Patent Laid-Open No. 4-222566, the raw rice is washed with fine bubble water to reduce the fungi in the raw rice and then dehydrated. After that, a method for producing packaged ready-cooked rice is disclosed, which is packaged and heat-sterilized to obtain ready-cooked rice.

Further, in Japanese Patent Laid-Open No. 4-222567, the raw rice is washed with water to reduce the fungi in the raw rice, dehydrated, packaged, heat-sterilized at about 60 ° C. and immediately cooked rice. Disclosed is a method for producing packaged and immediately cooked rice configured to obtain.

In Japanese Unexamined Patent Publication (Kokai) No. 4-335863, raw rice and water are placed in a container, heated appropriately and then air that has been sterilized is blown into the container to form fine water bubbles. Manufacture of packaged ready-cooked rice configured to be washed immediately with bubbling water to reduce fungi in the raw rice, dehydrated, then packaged, and subjected to repeated heat sterilization several times while changing heating temperature to obtain cooked rice A method is disclosed.

Japanese Unexamined Patent Publication (Kokai) No. 5-76295 discloses that raw rice, which is a raw material, is continuously sterilized by aseptic ultrafine air bubble water and then packaged in a synthetic resin packaging material to continuously cook and immediately cook. A device capable of producing rice is disclosed.

Further, in JP-A-5-76296, aseptic-treated air is mixed with appropriately heated pure water to form fine bubble water, and raw rice is washed with the fine bubble water. A method of manufacturing packaged ready-cooked rice configured to reduce the fungi in raw rice, further treat it with chemicals, dehydrate it, package it, and repeat heat sterilization several times while changing the heating temperature to obtain instant cooked rice. It is disclosed.

The above-mentioned JP-A-4-222566, JP-A-4-222567, JP-A-4-335863, JP-A-5-76295 and JP-A-5-76.
According to the method for producing packaged ready-cooked rice described in Japanese Patent Publication No. 296, it is possible to reduce bacteria and to obtain packaged ready-cooked rice with stable quality even during the summer distribution period. The storage period is usually about 2 to 3 months, and there is a demand for a method for producing package-washed rice that can be stored for a long period of time.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for producing package-washed rice which is excellent in taste and which can be stored for a long period of time without causing cracks or the like in rice grains. And Another object of the present invention is to provide a method for producing package-less washed rice which can be stored for a long period of time without requiring temperature control at the distribution stage.

[0013]

A method for producing long-term storable packaged non-washed rice according to claim 1 of the present invention is a method of vibrating rice that has been subjected to rice polishing treatment using an ultrasonic vibration plate to powder the surface of the rice. A step of removing water and a step of washing rice to add water to the rice after the step of polishing to remove the powder using an ultrasonic vibration plate, and a water content of the washed rice to be 10 to 15% Drying process to dry up to 50%, the rice after the drying process is exposed to pressurized water of 5 to 20 atm to bring the moisture content of rice to 40 to 45%, and the rice after this pressurized water process has a moisture content of about 30%. Dehydration process to dehydrate to a certain degree, alpha-drying process to dry the dehydrated rice to a moisture content of 23 to 25% with a far infrared dryer, sterilization process to irradiate the dried rice with ultraviolet light, and this sterilization treatment And a vacuum packing process for vacuum packaging rice.

By adopting such a constitution, the rice can be forcibly impregnated with water in the pressurized water step and dehydrated to remove impurities inside the rice which cannot be removed by ordinary washing rice, so that it can be preserved. It is possible to obtain package-washed rice having good properties and good taste. In addition, the far infrared rays dry the rice and convert it into alpha, which finally reduces the water content to 23%.
Since it is set to ~ 25%, rice can be cooked quickly, and the flavor of rice can be maintained even when dried. Moreover, since the water content is high, there is no cracking on the surface of the rice grain, and even if this dry rice is mixed with water during cooking, the water does not become cloudy, so it is not necessary to wash the rice again and it can be used as it is for cooking rice. be able to. In addition, since it has a sterilization process by irradiating dried rice with ultraviolet rays, after thoroughly sterilizing various bacteria etc. on the rice grain surface of washed rice that has been washed and dried to an appropriate moisture content, it is quickly vacuum packed. Therefore, it is particularly suitable for long-term storage, and can be stored at room temperature for a long time without temperature control at the distribution stage. In the pressurized water process, by using a seasoning liquid, an auxiliary solution liquid such as nutrients, etc. as pressurized water, it is possible to obtain package-unwashed rice for cooked rice and package-washed rice supplemented with nutrients.

According to a second aspect of the present invention, in the method for producing long-term storable unwashed rice in packaging, the rice which has been subjected to the pregelatinizing and drying step is dried with a far infrared ray drying apparatus equipped with a centrifugal separator. The first α-drying step is performed, and the dried rice is dried with a far-infrared dryer equipped with a blower to obtain a water content of 23-
The second step is a second alpha-drying step of drying to 25%. By adopting such a configuration, the rice can be gelatinized without being excessively dried, so that the water content can be efficiently adjusted to the range of 23 to 25%.

Furthermore, the method for producing long-term storable unwashed rice according to claim 3 encloses an oxygen scavenger together with the dried rice in the vacuum packing step. By adopting such a configuration, even if oxygen is generated from rice adjusted to a water content higher than usual, it can be absorbed by the oxygen scavenger, so that the flavor of rice can be maintained for a longer period of time. Can be saved.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION A block diagram of a process for producing packaged unwashed rice according to a first embodiment of the present invention is shown in FIG. 1, and the present invention will be described in detail below with reference to this block diagram.

First, the milled rice is placed on an ultrasonic vibrating plate to vibrate the rice to remove powder such as bran remaining on the surface of the rice (grinding step). Then, the rice after the grinding process is transferred by a conveyor and put in a rotatable basket of 1 mm mesh, and while rotating the basket, a wind speed of 4 m /
This powder is scattered by applying a wind of about 30 ° C for a second.

Next, in the rice washing process, the rice flour content after the polishing process is removed. In this washing rice, the raw rice and an amount of water in which the raw rice is completely immersed are supplied into a raw rice storage container equipped with an ultrasonic vibrating plate, and the ultrasonic vibrating plate is vibrated. Bran, dirt, various fungi and the like attached to the rice grains are released from the surface of the rice grain. On the other hand, air bubbles rise from the bottom of the raw rice storage container due to the vibration of the ultrasonic vibration plate. Then, the bran, dirt, various fungi and the like released are taken into the rising bubbles, and the bubbles reach the surface of the water so that the bubbles are lifted. At this time, for example, by flushing about 1 liter / min of water per 10 kg of rice in the raw rice storage container to wash away excess water, the dirt floating on the water surface can also be discharged together. Washing rice as described above is performed until the bran content remaining on the surface of the rice grain is sufficiently removed. By washing rice with the ultrasonic vibration plate and water in this way, it is possible to improve the removal efficiency of rice bran etc., so that not only does the color of cooked rice take on a yellowish color, No bran smell left on cooked rice. Furthermore, since it is possible to mechanize the rice washing, it is possible to shorten the rice washing time.

The rice thus washed is centrifuged at about 30 ° C. at a wind speed of 4 m / sec while reducing the water content by centrifuging.
It is dried by applying the air to a water content of 10 to 15%, preferably about 13% (drying step). By reducing the water content in this way, the rice easily absorbs water in the pressurized water process described below.

Then, the rice dried in the above step is added to 5 to 20
1) Rice is exposed to pressurized water at atmospheric pressure
Exercise for about a minute (pressurized water process). In this way the water content
After being dried to 10 to 15%, the inside of rice can be forcibly impregnated with water by exposing it to pressurized water, and the moisture content of rice can be set to 40 to 45%. In addition,
As the pressurized water, it is of course possible to use ordinary tap water, and by using a seasoning solution in which amino acids, scallop extract and the like are previously dissolved, and an extract such as potato and soybean, as cooked rice or red rice. It can be suitable. Moreover, the nutritional defects of rice can be supplemented by using a nutritional supplement solution containing calcium, various vitamins and the like.

The rice impregnated with water in the pressurized water process as described above is transferred to a centrifuge and dehydrated, so that the water content of the rice is about 30% (dehydration process). In this step, by reducing the water content of the rice that was raised to 40 to 45% in the pressurized water step, it is possible to remove the components that cause dirt and odor that have penetrated into the inside of the rice. It is possible to improve the shelf life and taste of rice.

Next, the dehydrated rice is dried by a far infrared dryer (alpha drying step). In this α-drying step, first, a dryer having a centrifugal separator in a furnace having ceramics that emits far infrared rays attached to four surfaces is used, and rice is transferred into the centrifugal separator and the rice is dried by the far infrared dryer. Surface temperature of 30-35 ℃ for about 3 minutes to dry (the first α
Chemical drying process). Next, this rice is laid on a 1 mm mesh conveyor so that the thickness of the rice is about 4 mm, and further dried by passing through a region of a far infrared heater which is a far infrared dryer equipped with a blower (No. 2 gelatinization and drying step). Drying conditions are as follows: Far-infrared heater temperature 100-300 ℃, air temperature 30 ℃, air humidity 10%.
± 2%, wind speed 4m, distance between heater and rice is about 60cm, rice atmosphere temperature is about 30 ° C, so that the mesh conveyor can pass through the area by far infrared heater in about 15 minutes. Move slowly and adjust the water content to 23-25%. By drying with far infrared rays,
The enzyme in the rice grain can be inactivated so that it can be stored at room temperature for a long time, and an appropriate film can be formed on the surface of the rice grain to increase the umami taste of the rice grain. In addition, the surface temperature of rice is kept relatively low, and the residual moisture in the rice grains is
Since it is dried so as to be 25%, the surface of the rice grain will not be excessively dried, and there will be no cracks in the surface of the rice grain. Does not become cloudy, so there is no need to wash the rice again when cooking rice. Further, since it is dried at a low temperature, it does not destroy an appropriate film on the surface of the rice grain formed by irradiation with far infrared rays, and the effect that the effect of improving the taste of rice by the far infrared rays is not impaired. Play.

Then, the rice dried by this pregelatinization drying step is left to stand at room temperature or in a cool and dark room for a predetermined time, or cooled by air cooling, and then the rice having a thickness of about 4 mm is placed on a conveyor of 1 mm mesh. It is laid so as to become, and an ultraviolet (ultraviolet C) irradiation area of 30 to 45 cm in the middle of this conveyor is passed for about 30 seconds while slightly shaking the conveyor itself (sterilization step).

Furthermore, after the sterilization step is completed, it is immediately vacuum-packed. This vacuum pack is, for example, provided at the end of the conveyor of the above-mentioned sterilization process with a packaging machine for automatically weighing the conveyed dry washed rice and vacuum packaging it in a synthetic resin packaging material. Can be packaged. In the present invention, the final moisture content of rice is 23 to 25%, which is the optimum value in terms of the storability of rice and the shortening of the cooking time. Because oxygen may be generated due to the amount,
At the time of this vacuum packing, it is preferable to prevent oxidative deterioration of rice by enclosing an oxygen scavenger such as Ageless (trade name) and to further suppress deterioration of storage stability and taste.

The packaged rice obtained as described above can be immediately cooked by adding a predetermined amount of water to the rice without removing the rice from the packaging material and then washing and dipping it in water and holding it. It can be used as so-called non-washed rice.
In particular, the water content of dry rice is suitable for cooking rice, so the time until cooking is about 1/3 of that for normal rice cooking.
Can be shortened. In addition, the rice grain to be packaged unwashed rice in the production method of the present invention is not particularly limited, and can be applied to various rice grains such as sticky rice, sticky rice, and indica rice. In addition, the sterilization conditions are optimal, the washing is performed well, and since it is converted into alpha by irradiation with far infrared rays, the storage period at room temperature will be about one year, which is dramatically longer than before. In particular, there is almost no deterioration in eating quality during a storage period of about 90 days.

As shown in FIG. 2, unwashed rice 1 in which unwashed rice 1A is packaged, packaging bag 2 in which ingredient 2A in which dried hijiki, burdock, etc. are packaged, and dashi juice filled with dashi juice 3A The bag 3 and the bag 3 may be packaged as a set in a bag 5 or the like to prepare a cooked rice set 6. In this case, for example, simply put the unwashed rice 1A, the ingredient 2A, and the dashi soup 3A together with a predetermined amount of water in a pot of a rice cooker and immediately cook the rice as it is to cook the cooked rice easily and in a shorter time than usual. be able to. In addition, 4 is an oxygen scavenger enclosed in the unwashed rice 1 and the packaging bag 2.

Although the present invention has been described in detail above, the present invention is not limited to the above description and various applications are possible without departing from the concept of the present invention.

The present invention will be described in more detail with reference to the following specific examples.

Example 1 Non-glutinous rice was used as rice, and 10 kg of this rice that had been polished was vibrated using an ultrasonic vibrating plate to remove flour on the surface of the rice. This rice was placed in a rice washer equipped with an ultrasonic vibration plate, water was added up to about 1 cm above the rice just immersed, and the ultrasonic vibration plate was vibrated while running 3 liters of water for 3 minutes. . As a result, air bubbles floated from the bottom side of the container, and along with the air bubbles, dirt such as bran on the surface of the rice was released and removed to wash the rice.

The washed rice was taken out from the rice washing machine, drained with a centrifuge, and dried with air at an atmospheric temperature of 30 ° C. and a wind speed of 4 m / sec until the water content became about 13%.

This rice was exposed to high pressure water of 5 atm, and the rice was allowed to move for 1 minute in this water stream to make the water content of the rice about 40%. This rice was transferred to a centrifuge installed in a furnace with ceramics that generate far infrared rays on all four sides, dehydrated in a centrifuge without irradiating far infrared rays, and the water content was about 30%. . Subsequently, the rice was dried for 3 minutes at a surface temperature of 30 to 35 ° C. while being irradiated with far infrared rays.
Subsequently, the rice was laid on a 1 mm mesh conveyor equipped with a far-infrared heater equipped with a blower so that the thickness of the rice was about 4 mm, and the far-infrared heater heated area was laid on the mesh conveyor. Was allowed to pass in 15 minutes, and the water content was adjusted to 23 to 25%. The heating condition of the far infrared heater at this time is that the heater temperature is 100 to 30.
0 ℃, wind temperature 30 ℃, wind humidity 10% ± 2%, wind speed 4m,
The distance between the heater and the rice is about 60 cm, and the atmospheric temperature of the rice is about 30 ° C.
Met.

Then, the rice dried by the far infrared ray is left to cool in a cool dark room and cooled, and then the rice is laid on a conveyer of 1 mm mesh so as to have a thickness of about 4 mm. An ultraviolet ray C) irradiation area is provided, and a vacuum packaging machine equipped with an automatic weighing device is provided at the end of the conveyor, and is ageless (trade name) while weighing 450 g each.
It was vacuum packed together with it to obtain washed rice without packaging.

The unwrapped rice thus obtained can be cooked immediately without being clouded even if it is taken out from the packaging material and mixed with water, and the cooking time is the same as that for normal rice cooking. The time was greatly shortened to 1/3 hour. The taste was also good. Further, even after being left at room temperature for one year, no alteration or the like was observed and the taste was not deteriorated.

[0035]

The method for producing long-term storable unwashed rice according to claim 1 of the present invention is to polish the rice which has been subjected to rice polishing treatment using an ultrasonic vibration plate to remove dust on the surface of the rice. Step, a washing step of adding water to the rice after the polishing step to remove the powder using an ultrasonic vibration plate, and a drying step of drying the washed rice until the water content becomes 10 to 15% Then, the rice after this drying step is exposed to pressurized water of 5 to 20 atm to make the water content of the rice 40 to 45%, and dehydration to dehydrate the rice after this pressurized water step to about 30% Process, dehydrated rice is dried in a far-infrared dryer to a moisture content of 23 to 25%, alpha-drying process, sterilization process of irradiating dried rice with ultraviolet light, and sterilized rice is vacuum-packed Since it is composed of a vacuum packing process, the rice is forced to a pressurized water process. Water impregnating, since the normal-bran rice by dehydrating can remove impurities inside the rice can not be removed, it is possible storability get a good packaging pre-washed rice with good taste. In addition, the far infrared rays dry the rice and convert it into alpha, which finally reduces the water content to 23%.
Since it is set to ~ 25%, rice can be cooked quickly, and the flavor of rice can be maintained even when dried. Moreover, since the water content is high, there is no cracking on the surface of the rice grain, and even if this dry rice is mixed with water during cooking, the water does not become cloudy, so it is not necessary to wash the rice again and it can be used as it is for cooking rice. be able to. In addition, since it has a sterilization process by irradiating dried rice with ultraviolet rays, after thoroughly sterilizing various bacteria etc. on the rice grain surface of washed rice that has been washed and dried to an appropriate moisture content, it is quickly vacuum packed. Therefore, it is particularly suitable for long-term storage, and can be stored at room temperature for a long time without temperature control at the distribution stage.

In the method for producing long-term storable unwashed rice according to claim 2, the rice after the pressurized water step in the α-drying step is dried by a far infrared ray drying device equipped with a centrifugal separator. Since it is composed of an α-drying process and a second α-drying process in which the dried rice is dried to a moisture content of 23 to 25% by a far infrared dryer equipped with a blower,
Since the rice can be gelatinized without being excessively dried, the water content can be efficiently adjusted within the range of 23 to 25%.

Furthermore, in the method for producing non-washed rice which can be stored for a long period of time according to claim 3, since the oxygen absorber is enclosed together with the dried rice in the vacuum packing step, the water content is higher than usual. Even if oxygen or the like is generated from the rice prepared as above, it can be absorbed by the oxygen scavenger, so that it can be stored for a longer period of time without impairing the flavor of the rice.

[Brief description of the drawings]

FIG. 1 is a block diagram showing steps of a method for producing package-washed rice to which the present invention can be applied.

FIG. 2 is a schematic view showing an example of use of unwashed packaged rice produced by the method of the present invention.

[Explanation of symbols]

 1 Unwashed rice in packaging 1A Unwashed rice

Claims (3)

[Claims] 1. A polishing step of vibrating the rice that has been subjected to rice polishing treatment using an ultrasonic vibration plate to remove dust on the surface of the rice, and adding water to the rice after the polishing step to use an ultrasonic vibration plate. And a step of drying the washed rice to dry the washed rice until the water content becomes 10 to 15%, and the rice after this drying step is exposed to pressurized water of 5 to 20 atmospheres The water content of 40 ~ 45%, the dehydration step of dehydrating the rice after this pressure water step to about 30% water content, and the water content of this dehydrated rice with a far infrared dryer 23 ~ 25% It can be stored for a long period of time, which is characterized by including a gelatinization drying step of drying up to dryness, a sterilization step of irradiating the dried rice with ultraviolet rays, and a vacuum packing step of vacuum-packing the sterilized rice. Non-washed rice manufacturing method. 2. The first α-drying step of drying the rice after the pressurized water step in the α-drying step with a far infrared ray drying device equipped with a centrifugal separator, and the dried rice with a blower. The method for producing non-washed rice which can be stored for a long period of time according to claim 1, which comprises a second pre-drying step of drying to a moisture content of 23 to 25% with a far infrared dryer. 3. The method for producing non-washed rice which can be stored for a long period of time according to claim 1 or 2, wherein an oxygen scavenger is enclosed together with the dried rice in the vacuum packing step.