JPH02242647A - Washed and dried rice, its production and packaging of dried and washed rice - Google Patents

Abstract

PURPOSE:To obtain washed and dried rice which can be cooked simply by adding water thereto by washing polished rice, dehydrating to a water-content of <=16% and sealing in an air-tight packaging material in a state to leave little space in the package. CONSTITUTION:Polished rice is stirred at a high speed in a state immersed in water to effect the washing of the rice and the removal of bran within an extremely short time. Immediately after the above process, the washing water and the water attached to the surface of the rice are remove to obtain the objective washed and dried rice having a water-content of <=16%. The washed and dried rice is packaged with an air-tight packaging material in a state to leave little space between the rice and the packaging material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to dry washed rice that can be cooked simply by adding water, a method for producing the same, and a method for packaging the washed rice.

[Conventional technology]

Consumers wash rice by changing the water many times each time they cook it. This is troublesome and also causes sewage pollution.
If possible, it would be better to wash and process the rice before it reaches the consumer, but there are problems that prevent this from happening, and nothing has been put to practical use yet. Traditionally, rice that has been washed and still wet has been available everywhere, but there has never been rice that has been dried.To an outsider, this may seem like a simple matter.

The problems that are hindrances are spoilage and pulverization of rice. In other words, when rice is washed, it absorbs water during that time and its moisture content increases, causing it to rot or mold to grow.If rice is dried to avoid this, the rice will first crack. Furthermore, the grains become crushed, so even if you cook them, you end up with sloppy rice that cannot be used as rice at all. Therefore, once polished rice is soaked in water, if it is dried, it will inevitably crack and break into granules. Nothing existed at all. Even if there were, it would only be "r dry washed cracked rice" or "dry washed cracked rice" before the failure.However, although the field is different from the product of the present invention, the following did exist. .

■There was a method of half-cooked rice in which the high-moisture rice was heat-treated and sealed in sealed packaging after washing to prevent spoilage and mold, but it was not widely used because it tasted bad and the cost of preventing spoilage was high. is the current situation. Also, there is polished rice, which is not washed in water, but is polished rice that is polished without adding a small amount of water (approximately 2% or less) to remove the bran from the grain. Because the wood was not soaked in water and washed, the bran powder in microns and the small cave-shaped germ removal marks have entered the countless minute depressions of the wood surface that cannot be seen with the naked eye. Since it is impossible to wash away the bran powder that is present, the opening value (the turbidity value of the washing water during rice washing according to the measurement method of the Japan Rice Milling Industry Association) is 0.
All turbidities described in this specification are the same) are 100 P, P, M
Therefore, when cooking rice, it is only necessary to wash and rinse the rice 5 times instead of 10 times for ordinary polished rice, so this does not mean that washing the rice is not necessary. Rice may be washed and water removed before rice is harvested. In this case, the rice grains crack or become sand grains, but since they are ground into powder, the cracks and crushed grains do not pose any problem. This is because it is not rice that is cooked for rice.

As mentioned above, the only type of conventional rice for cooking that is washed in advance and does not need to be washed by the consumer is the high-temperature processed rice mentioned in (2) above, but this is a high-cost rice that has been subjected to heat treatment, etc. As mentioned above, it is not mentioned because the alpha-ization makes it taste bad and taste like just recooked rice. However, this is more like a half plate than rice, and is different from the field of the present invention.

[Problem to be solved by the invention]

In this way, in the past, there was no such thing as raw rice that did not require washing, but due to the complexity of rice cooking and the prevention of polluted water, dry washed rice has become popular. In view of these points, the present invention, which has been requested by consumers for a long time, has been developed to create "dry washed rice" that consumers can cook without washing and that does not lose its flavor.
This invention discloses a method for producing the same. A further object of the present invention is to provide a packaging method that can prevent surface roughening of rice grains during transportation of the washed rice.

[Means to solve the problem]

The technical means of the present invention is dry-washed rice that is obtained by washing polished rice with water and removing water to a water content of 16% or less, and the method for producing it includes a washing process in which polished rice is stirred and washed in water. and a water removal process provided immediately after the water washing process,
Rice is washed in water and water is removed in a short period of time so that the water content of the rice grains after passing through the washing and removal steps is 16% or less. Further, as a packaging method, there is a method of wrapping the washed rice in an airtight packaging material, deaerating the rice so that there are no excess voids inside, and then sealing the rice.

[For production]

Generally, the reason that cracks appear in rice that has been washed and dried is that the rice grains, which are susceptible to strain, expand and contract partially each time they absorb water and remove water, causing strain. This is because it is possible. Therefore, when washing rice or removing water, expansion and contraction, which can cause distortion, do not occur.
If the amount of water absorbed and removed can be kept to a small amount, cracks will not occur even if polished rice is soaked in water, washed, and dried. By the way, polished rice has extremely unique physical properties with respect to water absorption, and it is necessary to understand this first before dealing with it.

That is, polished rice reaches a saturation point of about 30% water content in about one hour after being soaked in water. Of course, this time also varies considerably depending on water temperature and rice quality. However, in any case, the relationship between the immersion time and the rise in water content does not proceed at a constant rate, but rather at a rate of reversal. Therefore, immediately after immersion,
The amount of water absorbed in the first second was the steepest at first, comparable to the amount absorbed in the last 10 minutes, and even when analyzed for that first second, it was higher than the amount of water absorbed in the last 0.1 seconds. It goes without saying that the amount of water absorbed in the first 0.1 seconds of , a is much larger. As described above, regarding the water absorption characteristics of rice, the water absorption rate decreases at an accelerating rate as 1 hour ffff passes immediately after being immersed in water. Therefore, immediately after soaking, rice absorbs a considerable amount of water even for a very short time, so washing the rice should be completed within a short period of time and the water should be removed immediately. on the other hand.

In connection with this, it is necessary to consider the washing characteristics of polished rice. In other words, there are countless minute depressions on the surface of F11 rice that cannot be seen with the naked eye, and in order to remove the starch grains and bran powder that have entered them, it is necessary to soak the rice grains in water. It is necessary to stir and wash the rice at least 30 times.

The reason for this is that the depressions where the bran powder etc. have entered are deeper than the opening surface, and most of them are narrow openings on the order of microns.
Since it is the first page, the rice bran that has entered the back of the page is 1f I￥F.
The only way to remove this is to soak it in water and while it is vigorously agitated, suspend the bran powder etc. in the water and wash it away.

However, as mentioned above, such rice washing needs to be carried out within a short period of time. Based on such considerations, the present invention was developed by washing polished rice soaked in water to remove the bran in a very short time using a rice washing process in which the rice is stirred at high speed, and then immediately subjected to a water removal process. It performs cleaning water and removal of water adhering to the surface. The washing time per grain is such that the water content of the rice after water removal does not exceed 16%. Moreover, the number of times of 11 stirring is performed 30 times or more within that time. As a result, it is possible to obtain dry washed rice of regular grain size without cracking, let alone pulverization. Moreover, even if the rice is soaked in water again and washed, the water will not be absorbed, and the turbidity will be less than 7 GP, P, M.

Note that the turbidity values 7f31), P, and M are the lowest limits of the numerical values in the measurement method of the Rice Milling Industry Association, and turbidity values lower than these, that is, when the washing water is clean, cannot be measured. That's what I have to say. Of course, until now there has been no rice with such high sugar-removed dust that it cannot be measured using this measuring method. It was too low, and it was impossible to measure nl'lIq using this measurement method.However, this method was used because there is no other method to objectively express the degree of turbidity of rice washing water. Therefore, in this specification, "76
The expression “P, P, M or less” refers to the conventional il
This means that the turbidity is so low that it cannot be measured using the l'l method, which means that it is considerably lower than r.

In addition, in this specification, the expression "dried washed rice" refers to "drying", but rice grains must be stored at room temperature to the extent that they do not rot or develop mold, i.e., the moisture content is 16% or less. JH is the water content state. or.

The meaning of ``cracks'' in rice grains refers to cracks that can be clearly seen with the naked eye. Furthermore, the meaning of ``polished rice'' 1 includes not only completely polished rice but also 5 excessively polished rice and semi-polished rice.

Also, the meaning of ``washing rice'' or ``mizurin'' is to wash rice grains by stirring them in water that is so strong that they can be submerged in water.

Next, the dried and washed rice of the present invention is packaged in a low state. The surface of dry-washed rice is more brittle than that of rice washed with water, and when the rice grains rub against each other during transportation, the surface of the rice grains becomes rough, resulting in countless minute scratches, which deteriorates the taste. becomes. For this reason, it is necessary to prevent the rice grains from rubbing against each other during packaging.This objective can be achieved by the packaging method of the present invention. That is, since the package is a hermetically sealed package with almost no surplus air space between the wrapped dry washed rice and the packaging material, the movement of the rice grains is suppressed and the positional relationship between each grain remains almost unchanged. Therefore, even if the packaging is placed upright or laid down during transportation,
Rice grains do not rub against each other in the bag, and no roughness occurs.

Furthermore, even if external pressure is applied during storage or transportation, it is prevented from being applied to the internal rice grains, so rough skin and sand grains do not occur.

Originally, rice was packaged in packaging material with ventilation holes, unless it was packaged in vacuum bags or bags filled with inert gas. There are many reasons for that.

The first reason is to maintain the quality of rice. In such a packaging form, when the bag is being transported, the package may be stood up or laid down, but the apparent volume of the rice grains within each bag changes each time. That is, when the package is laid down on its side, the rice grains become stiff and have the smallest apparent volume, and when the package is placed upright, the rice particles fT move downward and become thicker, increasing the apparent volume. The increased apparent volume is accounted for by air entering through the ventilation holes in the bag material.1 When the bag is placed upside down and laid down.

As the rice grains inside spread out and the apparent volume becomes smaller, the excess air is released through the ventilation holes of the packaging material.
It will be served. In this way, when rice is packaged, the groups of rice grains inside the package move each time they are stood up or laid down, and at that time, the rice grains rub against each other.
Although it cannot be said that there are no harms in either way, dry-washed rice removes the bran powder, or so-called "R-cloth", that has adhered to the wood surface during washing, so the rubbing of the bare wood surfaces against each other is a problem. However, in the packaging method of the present invention, the excess air inside the package is generally removed and sealed when the rice grain group has the smallest apparent volume, so the orientation of the package changes and the apparent volume increases. Even if the rice grains try to do so, the amount of air cannot enter from the outside, so the rice grains can be maintained in their original form with the smallest apparent volume, and as a result, the rice grains do not rub against each other.6th ,
Even if external pressure is applied during storage or transportation, this pressure can be prevented from being applied to the rice grains inside. Normally, when this type of rice is packaged and stored, it is stacked horizontally, but in this case, the present invention In this packaging method, as mentioned above, the packaging material is airtight, and the packaging material is degassed and sealed so that there are no excess voids. Since the apparent volume is small, in other words, the surplus space is largest between the rice grain group and the packaging material. Therefore, even if this package is overloaded with packages stacked on top, pressure will be applied to the air occupying this extra space, and the rice grains will not be under much pressure. In addition, the term "airtight packaging material" in the present invention refers not only to materials with no air permeability, such as aluminum vapor-deposited plastic films or special plastic films, but also to materials with no air permeability, such as aluminum vapor-deposited plastic films or special plastic films. It also has the meaning of "low", for example.

This includes regular polyethylene film and plastic coated paper bags.

In addition, in this specification, the meaning of "sealed so that there is almost no excess void" means that the pressure is reduced to below atmospheric pressure and the product is pressurized and tightened, as in general vacuum packaging. Rather, it refers to a degree of degassing and sealing that, although there are some voids, the rice grains do not move downwards and become thick when the package is placed upright.

[Example 1] The agitator of a known rotary continuous rice washer was rotated at 600 revolutions per minute, and a water removal device was continuously installed at the outlet of the agitator to configure a water washing process and a water removal process. While water at 3°C was injected into the rice washer, Nagiho polished rice produced in Wakayama Prefecture in 1985 and having a moisture content of 14°2% was continuously fed at a rate of 1 kK per minute. The polished rice enters the injected water that is moving in the rice washing tank of the rice washing machine, is stirred in the water, is washed, and then discharged from the outlet of the rice washing machine together with the washing water, and is immediately transferred to the water removal equipment for the next process. The cleaning water and adhering water are removed here and discharged from the water removal device. During that time, the time from when each grain of polished rice was soaked in water in the rice washing tank until it was discharged from the water removal device was 45 seconds (most of the time was spent in the water removal process). The rice freshly removed from the water removal process had a moisture content of 15.9% and was left indoors for 30 days.
Even when the rice is polished, it does not become rotten or moldy, and only 1 out of 10 grains cracks (the original polished rice had cracks in about 1 out of 50 grains). ), and there was no pulverization (excluding the pulverization from the beginning), and the original sized group remained. However, when the washed rice is washed again, the washing water has a turbidity of 76P.
, P, M or less, and I cooked it by just adding water without washing it,
Because the rice has been thoroughly washed, it has no bran odor and remains fresher than regular rice, making it delicious.

Furthermore, the washed rice treated as described above is placed in a polyethylene packaging bag, and while it is lying on its side, a light pressing force is applied using flat plates from both the top and bottom sides to flatten it and expel most of the excess air in each bag. After that, it was sealed. When this was lifted by hand and shaken by standing it upright or tilting it diagonally, there was almost no transfer of rice grains within one bag. In addition, when this was subjected to loading and delivery tests, the rice grains did not become rough.

[Example 2] The rotation speed of the rice washing machine was set to 1800 revolutions per minute, and the water removal process was performed using a high-performance water removal device.
At the same time, 1985 Wakayama prefecture-produced Japanese rice with a moisture content of 13.8% was continuously added at a rate of 10 minutes per minute. In this case, the time from when the polished rice was soaked in water in the rice washing tank until it was discharged from the water removal device was about 5 seconds. The rice that has just come out of the water removal process has a moisture content of 14.5%, and even if it is left indoors for 30 days, there is no rotting or mold growth, and not a single rice grain has cracks. Without (
(Excluding the cracked rice from the beginning), and of course, it did not become crushed (excluding the crushed rice from the beginning) and remained the original sized group. When the washed rice was rewashed, the turbidity was 76 P, P, M or less, and even if it was cooked without washing with just water, it remained fresh and tasted slightly better than normal rice. Rice and its production methods can be extremely sophisticated. However, although a known continuous rice washing machine may be used for the water washing process of the present invention, some modification is required. In other words, conventional continuous rice washing machines usually rotate at about 200 revolutions per minute, but in the case of the present invention, the rice washing tank is preferably small in diameter and has a speed of at least GOO revolutions per minute. Although it is determined by the relationship, the point is that even after the supplied polished rice has been stirred the number of times necessary for sufficient washing within 4 tons, the It is designed so that the moisture content, so-called internal moisture content, is 16% or more. To explain in a little more detail, rice does not yield in the first place! After J, the moisture content of brown rice is 15, except for some areas.
It is mandatory to dry to below %.
If it is higher than that, it will not pass the test, so it is usually 13% to 1
It is distributed as brown rice with a moisture content of 4%. Furthermore, even if tempering is carried out, it is unavoidable that about 0.5% to 1% of moisture evaporates during the milling process, resulting in a moisture content of about 14% when milled rice is processed. It is. In this way, there is no risk of rotting or molding with normal milled rice with a moisture content of around 14%, but when such milled rice is washed with water in the rice washing machine mentioned above, water washing (when it passes through the soda) is difficult. If the flowering time is long, water penetrates deeply into the rice grains, and even if the water adhering to the surface is removed, the internal moisture content becomes high and becomes a trap for rot and mold.In order to prevent this, internal moisture is If you remove it by ``h h'd, it will cause strain and cracks that will cause granulation, so it is recommended that you do not need to remove the internal moisture.
The moisture content when the water adhering to the surface is removed, that is, the internal moisture content, is 1
It is necessary to keep it below 6%, and to do so, it is necessary to determine the size of the tank in consideration of shortening the time it takes for rice grains to pass through the flower bed in the rice washer. In other words, generally speaking, if the tank is small with respect to the claws of the rice grains passing through, the time it takes to pass through the tank will be short, and if the tank is large, the flower seeding time will be long. In any case, it goes without saying that in the production method of the present invention, the time required to pass through the flower bed in the case of a conventional continuous rice washing machine must be an order of magnitude shorter, and the setting of the flower seed time must be made with precision. It is also necessary to take into consideration the water absorbency of the white rice and the temperature of the washing water. That is, the higher the water temperature, the faster the water absorption rate, so it is necessary to shorten the time it takes for the water to pass through the flower bed. The point is that in any case, when washing rice, the time should be set so that almost no water penetrates into the inside of the rice grains.The first factor is the rotation speed of the rice washing machine, and if the number of times the rice grains are stirred in water is small, Since the minimum required rice washing effect cannot be obtained, as mentioned above, if you want to stir as many times as necessary for sufficient rice washing within a short flowering time, it is necessary to increase the rotation speed of the agitator of the rice washing machine. There is a need to. The key is to set the rotation speed at which the required number of stirrings for sufficient washing of rice can be performed within the flower seed passage time, which is an order of magnitude shorter than in the past. still.

Sufficiently washed rice here refers to the extent to which the rice does not have a bran smell when cooked as is, that is, the extent to which the rice has been washed by the consumer within the membrane, and physically the surface of the polished rice is The countless minute depressions that cannot be seen with the naked eye, and the micron-sized rice bran powder that has gotten into the germ extraction marks, are removed, that is, when the rice is washed again. This refers to a state in which the washing water is hardly cloudy.

In this way, the rice is sufficiently washed and then discharged from the rice washer, but in the case of most rice washers, the rice grains are discharged together with a large amount of washing water.

Immediately, the water removing device installed in the latter stage of the rice washing machine removes not only the washing water but also the water adhering to the surface of the rice grains. Note that the water removal device may be any known device as long as it has the function of removing washing water and attached water;

It should not take a long time to remove the washing water.

This is because even though the rice grains are prevented from absorbing water during the rice washing process, it is pointless if the washing water is absorbed inside the rice grains because it takes time to remove the washing water during the water removal process. Among the well-known water removal devices, there is one that can remove most of the washing water that causes water absorption in a short time, almost instantly, so you should choose one. When milled rice is passed through the rice washing process and water removal process in the same manner as described above, the polished rice is washed and water removed in an extremely short period of time, so almost no water penetrates into the rice grains, and water is removed from the water removal equipment. When the rice is discharged, it has a moisture content of 16% or less, and even if it is left indoors for a long period of time, there are almost no cracks on the surface of the rice, and of course it does not turn into sand grains.

In addition, in Appendix A, it is easy to imagine that even though the adhering water has been removed from the rice grains after they have been discharged, the surface area has a higher moisture content than the inside; This means that one surface area with a high water content is thin and does not even crack. In other words, in the conventional concept, washing rice means that water is immediately absorbed into the inside of the rice grain, resulting in a high water content in the entire grain, and the only way to remove this is to dry it. It is. However, in the present invention, even if the rice is washed, the water content is high only on the very surface, and the water content is not increased to the inside, so the water content of the whole grain increases only slightly, but it is not It remains in its original dry state. This means a moisture content of 16% or less. It should be noted that the moisture on the surface of the freshly drained rice grain soon moves into the interior and becomes balanced.

In this way, the present invention processes all steps from washing to water removal in an extremely short period of time until it absorbs about 2% of water. This breaks down the idea that food must be cooked before drying.

〔effect〕

The dry washed rice of the present invention can be produced at a low cost, and when cooking rice, the water does not become cloudy even if it is put in a pot with water, and the rice can be cooked as is, which has been a long-held desire. It saves consumers the trouble of washing rice.Also, since most of the rice bran has been removed from the cooked rice, there is no smell of rice bran.

The result is shiny and delicious rice. In addition, the product of the present invention, from which most of the bran powder has been removed, maintains its freshness and preserves better than conventional rice, and furthermore, the rice washing method of the present invention requires more intensive and industrial sewage treatment. Because of this, the amount of rice bran powder that is currently discharged by each consumer across the country along with washing water is approximately 4% of the amount of rice consumed, which is approximately 400,000 tons of rice bran powder distributed throughout the country each year. River pollution can be prevented.

In addition, according to the packaging method for washed rice of the present invention, the movement of rice grains inside the package can be suppressed and external pressure can also be prevented, so that rice grains are not damaged due to stress during storage, and rice grains are not easily separated from each other during transportation. There is no rubbing, and no rough or broken rice occurs. For this reason, it becomes possible to safely deliver dry washed rice, which has difficulty in strength, using the current transportation method.

Claims (1)

[Scope of Claims] 1) Dry washed rice that has been washed with water and treated to remove water to a water content of 16% or less; 2) A process of stirring and washing the polished rice in water, and immediately after the washing process. The rice grains are characterized by being equipped with a water removal process provided in the washing process and water removal process, and washing the rice in water and removing water in a short time so that the water content of the rice grains becomes 16% or less after passing through the washing process and the water removal process. 3) A method for producing dried and washed rice according to claim 1, which is characterized by wrapping the dried and washed rice according to claim 1 in an airtight packaging material and sealing the rice so that there is almost no surplus void between the rice and the packaging material. How to package washed rice