JPH03154643A - Preparation of rice unnecessary to be washed and its apparatus - Google Patents

Abstract

PURPOSE:To prepare rice which does not need to be washed and has good taste and storability at low cost by washing rice within a short time and at the same time dewatering the rice without damaging the rice grains. CONSTITUTION:A centrifugal dewatering tub 30 which is rotary-driven and a transporting means 40 to move rice grains along the circumference wall of the tub 30 toward shaft direction and an evaporating and dewatering means 28 to evaporate water from the rice grains while the grains are transported are installed Washing process involving adding water to polished rice and mixing them is carried out and at the same time or immediate after the washing process, dewatering process to dewater from the washed rice grains is carried out until the increase of the water content of the rice does not become over 1%, and depending on the rice to be treated, the whole process is carried out, within a short enough period so as not to impregnate the rice with water beneath a first starch composite granular body row. As a result, rice which does not need to be washed and has good taste and storability is prepared at low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for producing wash-free rice that can be cooked immediately without polishing the rice, has a good shelf life, and can be easily produced. .

``Conventional technology'' Until now, proposals have been made for ``wash-free rice'' and ``rice that can be cooked without grinding,'' which can be cooked as is by adding water to the rice.

One of them is manufactured by, for example, a rice polishing device disclosed in Japanese Patent Application Laid-Open No. 1-218642. This publication discloses a technique for stirring rice without using water and further removing rice bran and the like using air flow.

In addition, 18-2 rice was thoroughly soaked in water and thoroughly washed.
High-moisture, unrinsed rice containing 0% wood is distributed in family restaurants and mass-cooking restaurants, but it is used for a short period of time and must be refrigerated if it is to be stored.

There is also a type of rice that is polished in a very short period of time and then offered to consumers as rins-free rice.

``Invention or problem to be solved'' However, such conventional technology is ``sharpening rice''
When cooking rice without understanding the facts, ``sharpening'' with water as a pretreatment process and subsequent soaking are essential for cooking delicious rice, and the technology disclosed in the above publication is essential. Since it does not use water,
In reality, rice was not polished, and even when the rice was cooked, it lacked flavor.

In addition, if high-moisture, unrinsed rice is used promptly, there will be no problems with the taste, but if it is stored for a long time, the rice may crack or become damaged, or the rice may grow moldy or bacteria, which may affect the taste when cooked. This caused the problem that it was not practical in terms of storage stability.

The purpose of the present invention is to provide a method and apparatus for producing wash-free rice that does not require refrigerated storage, frozen storage, sterilized packaging, etc., and is both labor-saving and delicious. Ru.

``Background of the Invention'' Wash-free rice that is both delicious when cooked, easy to produce with labor-saving, and has a good shelf life does not exist, and conventional wash-free rice that is polished in as short a time as possible does not. However, without elucidating the quality, water temperature, washing method, polishing level, etc., none of the products were able to gain approval and demand from consumers based on their taste judgment.

In the first place, ``rice polishing'' involves soaking rice in a sufficient amount of water, applying a little pressure to the rice in the water to add a washing effect, and removing the bran and rice grains that have adhered to the surface of the rice grains in the mixed turbulent flow. It has long been said that washing away adhering starch particles, etc., but in the conventional definitions of rice such as unwashed rice and washed rice, there is no clear explanation of what "rice polishing" means.

In this way, in the past, the meaning of "sharpening rice" had not been elucidated, but as a result of numerous taste tests and extraction experiments conducted by the inventor, it was finally clarified.

That is, as a result of research, it has been found that the substance that must be extracted and removed by ``rice polishing'' is aliuron residue, which will be explained below.

Ordinary white rice has a structure as shown in Figures 7 to 9. How to measure the water absorption rate of rice for 9 hours will be explained.

First, regarding the water absorption speed and measurement factors of rice, according to the graph shown in Figure 12 by the Food Science Society of Japan, which measured the soaking time of rice in water, it can be seen that there are extreme differences depending on the quality of the rice and the water temperature. When calculating the water infiltration rate for Japanese standard rice produced in Japan using the cross-sectional view of Sogote Figure 8, the thickness of domestically produced rice is 0.95 to 1.711 square meters. Divide the rice by half the thickness, taking 40 minutes as the time needed to absorb the water as quickly as possible.

0, 8 fat layer/40 minutes = 0. 33 In other words, how fast does water seep through the rice?

1- The fastest one is 0.33 seconds, the slowest one is 0.86
It will take seconds. Assuming that the material and osmotic pressure of the outer layer of rice are uniform, this calculated value can be determined to be the water infiltration rate.

The graph also shows that there is a large difference in the water absorption rate of 3 to 4 times depending on the water temperature and the quality of the rice.

Aliuron is generally a part of bran and is also called deep bran or aleurone layer, and has a fluid and viscous form at room temperature and pressure, and its main component is water-soluble. It is a complex of water-soluble proteins, water-soluble oils, and carbohydrates. Alliuron itself in brown rice is polished by a milling machine. In the case of normal milled white melon, numbers 8 to 92; I are thought to be removed along with the bran. The residue A is smeared on the outermost starch composite granule surface 1 of the rice grain, or enters between the first layer starch composite granules 2 due to the pressure during milling.

The only way to remove the Aliuron residue A that has entered and the Aliuron residue A that has been smeared onto the surface is by ``grinding the rice'', and the only way to remove it is by extraction with water.

When rice is washed with water, the water penetrates into the rice grains and causes each line of cell lines to swell, but when rice is washed normally, the rice starts cooking right away, so expansion is not a problem. ,
If we are going to provide unwashed rice, it is necessary to prevent water from entering as much as possible so that the taste does not change even if it is stored for a long time.

When we investigated the changes that affect the taste of rice grains when they are cooked, we found that when Aliuron residue A was extracted and removed, the two rows of starch composite grains in the outermost layer were damaged due to the intrusion of water. The rice grains become as shown in Figure 1θ, and due to uniform expansion and homogeneous swelling during cooking, the rice grains undergo the erosion and swelling action of water through the wounds on the outer surface during cooking, and as shown by the arrows in Figure 11. The rice grains expand non-uniformly by peeling or sagging from the rice grain body B in each direction.

It has long been widely known that rice grains of this type are unsuitable for use as rice for ordinary rice. To prevent this from happening, the key to delicious food is to extract all of the remaining 7-liuron A.

The difficulty in extracting the Aliuron residue A and in suppressing the increase in moisture content to 1% or less without damaging the two rows of the first layer starch composite granules was beyond description.

However, Aliuron residual vs A is on the outermost side,
The width of the two rows of starch composite particles in the first layer is 20 mm as shown in Figure 1O.
There are ~40 connections. Further, the time required for water to permeate the IJL is 0.33 seconds to 0.86 seconds as mentioned above, so the time required for two rows of first layer starch composite granules to completely absorb water is 0.33 to 0.86 seconds at the shortest. , 33 x 20 = 6.6 seconds The longest is 0.86 x 40 = 34.4 sho.From the taste experiment etc., we set the first layer's complete water absorption time as the target, and the number comes out to be about 30 seconds or less at room temperature. . It doesn't have to be exactly 30 seconds or less; it varies greatly depending on the rice, or the important thing is to complete the process within the first layer's complete water absorption time, and to avoid swelling due to water seeping between the first and second layers. be.

Figure 13 shows the relationship between the thickness of the water film on the surface of rice grains after washing with water and the subsequent processing time. The thickness is reduced to 3.5μ, and the increase in moisture is less than 1%.

Furthermore, Fig. 14 shows the relationship between the water content ratio after washing and the processing time when the water temperature is as low as 0 to 3°C.
Water intrusion time is slow, so water increases by 1% in 3 minutes of processing time.
It is as below.

As mentioned above, when rice is washed with water, the rice grains begin to absorb water from the moment they come into contact with water, and even if we assume that the rice has been completely dehydrated and dried by the time the rice has been polished to remove the adhering aliuron, the rice grains The degree of water inundation and erosion varies widely depending on the factors explained above.

Next, Aliuron residual e! To explain A and its extraction method, 1000g of commercially available white rice from fv-tsu is mixed with 2000cc, 15
The container was placed in water at a temperature of .degree. C., and the container was subjected to vertical motion of about .+-.31.degree. in the direction perpendicular to gravity, that is, in the up and down direction, at a rate of 120 times per minute for 2 minutes. At this time, if more than 3G
Let us not add f.

Immediately after that, separate only the water, filter it with 100" filter paper, put it in a cylindrical container with a height of at least 10 times the diameter, and
After standing still for more than 0 hours, 95% of the upper part was dried in a vacuum low temperature dryer.
Evaporative drying at c gives about 6.5 g of residue. This is the elemental substance that makes the residue A of rice taste bad.

The extraction method is to filter through filter paper and then concentrate using a hollow polymer filtration tube filter.

It is also possible to easily and quickly measure the concentration by creating a comparison table with the concentration extracted and measured using the vacuum drying method using a low-pressure low-temperature dryer as described above.

In addition, the substances remaining on the filter paper are mostly residues and impurities from the cellulose-rich outer layer of the sugar layer, and the substances precipitated at the bottom of the settling vessel are rice starch itself.

As a side note, even if you wash this substance again with clean water and remove only the starch and mix it in to an amount equivalent to 3% of the amount of rice just before normal cooking, the taste of the finished rice will be different. had no effect.

Furthermore, when we added Aliuron Residue A (approximately 0.65%) to rice grains that had just been washed with water and cooked rice, the taste of the rice was bran and slightly yellow. It was the same as rice that was cooked without being polished.

This extract is largely related to the white melon, variety, and production area of white rice, and its amount and properties vary greatly.

Aliuron residue A is a highly viscous liquid and solidifies when dried at high temperatures. It does not have much deliquescent property in water, and does not absorb water and dissolve even in normal air, and is a light greenish-yellow amber-colored substance.

Although it dissolves well in water, there seems to be a difference in the rate of dissolution when the concentration exceeds 1000 PPM, and if the pH is slightly acidic, the rate of penetration into the interior of the rice grain is slow, but the rate of extraction of Aliuron A is lower. It gets faster.

When a protease is added to water-soluble Aliuron residue A, it condenses and begins to precipitate. There is little change in lipase, justase, etc.

Next, when considering the advantages and disadvantages of centrifugal dehydration and net conveyor dehydration, it is necessary to first analyze the mass and surface area of rice grains. Although it is not appropriate to calculate based on the number of varieties of bamboo production areas, if you try to calculate the approximate value as a general goal, the average number of Japanese domestic rice per grain is 0.7 c + s2 ± 20% (estimated using 1 ft as a reference). Let's try it.

Assuming that the water film thickness of the water adhering to the surface is 1 OpL.

The amount of moisture that rises for the grain is 7 0, 0 as” x O, Ol m
m=0, 7 m g, i.e. 0.7 m
If the weight of the grains is calculated as approximately 24 mg, then 0.7/24=0.0291, resulting in an increase in water content of approximately 3%.

On the surface of rice grains, multiple starch grains are aligned, and the aligned walls are separated by hydrophilic protein membranes and have irregularities of about 5 to 10 μm.

By the way, the 1986 Sasanishiki is usually commercially available.

White melon 39 with a moisture content of 14.6% was treated with a coating similar to that of the embodiment of the present invention to be described later. Tatashi,
The processing time is quite long.

That is, at a water temperature of 15°C, pH of 6.5, and an air temperature of 25°C,
Water washing extraction was carried out for 30 seconds, centrifugal dehydration was carried out for 4 seconds at 35G, and gout centrifugal dehydration was carried out for 30 seconds at a relative humidity of 50% and a wind speed of 1 m/sec when passing through the rice grains.

As a result, the moisture content rose to 15.8%, and the white melon showed a temperature of 46 degrees. When I cooked the rice normally and tried it, I found that the white melon in the rice was good, but the gloss was poor and the taste was lacking in stickiness.

When this rice is observed with a magnifying glass, as shown in Fig. 15, the surface of the rice grain is observed in a plane as shown in Fig. 15 (A).
Thick cracks ran on the surface of the first layer starch composite granule 2, and thin mesh-like cracks were also formed in the first layer starch composite granule 2 itself. In addition, the 151st Z where the cut cross section was observed
In (B), a thick crack A penetrated deeply from the surface of the first layer starch composite granule 2 toward the center of the rice grain, and a slightly thick crack C was also observed.

Looking at this, it seems that the reason for the quality of the rice is that the deep cracks in the rice prevent it from expanding evenly with water during cooking, causing a change in the rate of gelatinization on the surface.

Therefore, it is considered necessary to wash the rice so quickly that the thin mesh-like cracks shown in FIG. 5 cannot be detected even by looking at the H dormitory with a magnifying glass.

The present invention has been made based on the above-mentioned problems and research, and aims to elucidate that "rice polishing" is a "washing and extraction action of adhering aliuron substances" and to perform rice polishing based on the results. As a result, for the first time, it has become possible to produce rice without washing, which does not require the rice polishing process that was always required before cooking.

``Means to solve the problem'' As explained above, by polishing rice in a short time of almost zero seconds under the most ideal conditions to overcome various inhibiting factors and minimizing the osmotic effect of water, rice can be prepared at room temperature. The rice can be washed under normal pressure and does not require sterilization or sterilization. In other words, if the two rows of the first layer starch composite grains on the surface of the rice grain are left intact after extracting the aliuron residue, the rice can be dehydrated and dried in a oven, resulting in delicious and fragrant rice that can be cooked later. Ru.

To extract and remove Aliuron residual % JA, use a solvent (water or acidic water) that is at least 100 to 1000 times the extraction value.
It is necessary to adjust the dissolved concentration so that it does not exceed 1000 PPM. If the water content exceeds 11,000 PP, the water content of rice grains will not change even though the washing action will slow down, making it difficult to operate the dehydration and drying action afterwards. As aliuron residues, the overall concentration of rice grains may increase by about 10 PP-.

There are large differences in the properties of rice depending on the region, type, and season of rice, and given these large differences, it is important to wash the rice for only a few seconds without adding a mechanically or physically strong washing action. "Rice polishing" to remove Aliuron residue, which can be as much as 4 oJL, is often difficult to do, and if the rice is exposed to water for a period of about 10 to 10 seconds, it may become waterlogged depending on the quality of the rice to be washed, water temperature, mechanical pressure, etc. There may be a large difference in the amount of residual water attached, and if this happens, no matter how much dehydration and drying is performed later, the taste will deteriorate due to cracks and distortions due to the depth of water intrusion.

However, in the past, when sharpening rice, as was commonly said, the rice was pressed down with the palm of the hand, turned over, and then pressed down again using the "underwater polishing process".
There is no need for sharpening.

Even if the rice in the water does not deviate, it is in a state where it is enduring the intrusion of water as it tries to expand, and the surface of the rice grains also has an extremely large coefficient of friction, so this type of rice polishing damages the rice grains. In many cases, it mainly produces unnecessary starch fragments, and it often serves as a supplement to the original extraction of aliuron.This is because we do not know that aliuron residue A is the source of anti-tastness. It is a posturing and a lie of common sense.

The force applied to the rice grains is light, quick, and numerous, and a shock similar to vibration is more effective and desirable.

When the water film reaches 3% by weight of rice grains, it is impossible to separate and remove the rice grain surface water that exists between 5-lop unevenness using centrifugal force.The load of centrifugal force must be applied to reduce the water film to below the top level. (G) must be raised by - or even two digits, which would damage or distort the rice grains themselves, making it impractical.

It is advantageous to use centrifugal force as a dehydration method until the film thickness of the water adhering to the rice grains reaches 10:1, and it is essential to evaporate the water below that, that is, when the rice water ratio is within Zoo:3. be. In this case, it depends largely on the rice and the air volume, and the air volume and the amount of stratification, which greatly affect the taste of the finished unwashed rice.

In addition, with the ventilation drying method using a net conveyor, there is too much difference in the strength of the wind that passes between the rice grains, resulting in difficulty in controlling the moisture content of the rice grains, and because it depends on the airflow itself, there is a strong wind loss, or pressure loss. The method using a net conveyor is superior to the centrifugal dehydration method because it avoids the destruction of rice grains due to centrifugal force, but other methods are superior to the centrifugal dehydration method. It is either the method or the tube delivery.

It depends on the rice variety, but generally the water temperature is around 10-25℃,
It is desirable to polish and dehydrate the rice within 10 to 30 seconds at a relative humidity of 40 to 70%.If the air flow and humidity exceeds 30 seconds, the rice's inherent water content will be lost rather than the water film itself. 3.
When the time exceeds 0 seconds, the water infiltration speed reaches the surface first as mentioned above.
It has reached the depth of the composite grain layer, and even if it is evaporated from this point, the multiple grain partition membrane expanded by the arriving water will not return to its original state, and it will become a wound and cannot be uniformly l11n.
There is a risk that it will turn into rice grains as shown in Figure 1.

White melon 40-41 whitened by a grinder type rice polishing machine
For rice with a high degree of whiteness, such as 100% whiteness, it is possible to obtain good-tasting, unrinsed rice within a few seconds with mild mechanical shock washing at extremely low temperatures.

On the other hand, Hokuriku or Hokkaido rice, which has a low white melon temperature of about 37 degrees and has a hard rice quality, has a high temperature, requires a long soaking time, and has a strong mechanical washing action. It cannot be washed-free rice that has undergone "grinding".

In the end, in order to make good quality rice without washing, it is better to suppress the increase in water content by self-processing for as short a time as possible after considering various conditions, and if the increase exceeds 1%, the taste will deteriorate significantly. .

In order to wash the rice grains without damaging them, it is necessary to minimize the mechanical washing action and carefully adjust the washing method, which emphasizes the extraction action of the water itself, that is, differences in rice quality. .

Based on the above premise, 1. The gist of the present invention is as follows: 1. A washing step in which water is added to polished rice, mixed and stirred; It is equipped with a dehydration process that dehydrates water to the extent that the increase in water does not exceed 1%, and the entire process is carried out in the first stage depending on the rice to be processed.
A method for producing wash-free rice, characterized in that the process is carried out in a short time without allowing water to penetrate below the rows of layered starch composite grains.

2. A washing process in which water is added to the polished rice and mixed and stirred, a rinsing process in which water is poured after the washing process to wash away the attached B, and the washing process is carried out simultaneously or immediately after the washing process and the rinsing process, and the rice is washed with water. The process includes a dehydration process in which rice grains are dehydrated to the extent that the moisture content does not increase by more than 1%, and depending on the rice to be processed, the entire process or a short process in which water does not enter below the rows of starch composite grains in the first layer. A method for producing wash-free rice, which is characterized in that it can be made in hours.

3 When the water temperature of the washing water is about 10 to 25 degrees Celsius, the processing time for the increase in moisture content of rice grains to not exceed 1% is within about 10 to 30 seconds depending on the rice being processed. Item 1 characterized by.

The method for producing wash-free rice according to item 2.

4. When washing wood with cold water at a temperature of about 0 to 5 degrees Celsius, the processing time until the water content of the rice grains increases by no more than 1% is within about 60 seconds depending on the rice being processed. Item 1 is characterized by:

The method for producing wash-free rice according to item 2.

5. A washing process in which water is added to the polished rice, mixed and stirred, a rinsing process in which water is poured after the washing process to wash away deposits, and a first dehydration process using centrifugal force is carried out simultaneously with the washing process and the rinsing process. and a second dehydration step by evaporation, which is carried out simultaneously or immediately after the washing step and the rinsing step, and dehydrates the washed rice grains to an increase in water content not exceeding 1%. A method for producing wash-free rice, characterized in that, depending on the rice, all processes are carried out in a short time so that water does not penetrate deeper than the first layer of starch composite grains.

6 The first dehydration step using centrifugal force is carried out until the film thickness of the water adhering to the rice grains reaches approximately 10%, and the second dehydration step using evaporation is performed until the water content of the rice grains increases by no more than 1%. 5. The method for producing wash-free rice according to item 5, characterized in that the method is carried out so that the following results are obtained.

7 The first dehydration process using centrifugal force is carried out until the moisture content of the rice grains increases by about 2.5%, and the second dehydration process due to evaporation is carried out until the moisture content of the rice grains increases by no more than 1%. 5. The method for producing wash-free rice according to item 5.

8 The second dehydration step by evaporation is non-flame thermal evaporation, with an ice temperature of about 10 to 25°C and an atmospheric relative humidity of 40 to 70°C.
%, the time it takes for the moisture content to increase by no more than 1% is l.
The method for producing wash-free rice according to items 5, 6, and 7, characterized in that the time is within about 30 seconds.

9 The water used is 1 of the aliuron attached to the rice grains.
Items 1 and 2 characterized by being about 00 to 1000 times
Items...--A method for producing wash-free rice according to item 8.

10. The method for producing wash-free rice according to items 1, 2, . . . , 9, wherein the water used is prepared to be slightly acidic.

11 Items 1 and 2, characterized in that each step is adjusted to such an extent that alluron residues on the surface of the milled rice are removed, and the T51 layer starch composite grain array on the surface of the rice grains is evenly arranged. . . . The method for producing wash-free rice according to item 10.

12 Items 1 and 2: Polished rice with a moisture content that can withstand indoor storage at room temperature and humidity, and the amount of residual aliuron, which is an ingredient that affects the flavor of rice, is 2g or less per 1000g of polished rice.
...The method for producing wash-free rice according to item 11.

13. Wash-free rice characterized by comprising a rotationally driven centrifugal dehydration tank, a conveying means for moving the rice grains in the axial direction along the peripheral wall of the centrifugal dehydration tank, and an evaporative dehydration means for evaporating the rice grains while conveying them. manufacturing equipment.

14 A centrifugal dehydration tank that can be rotated is installed in the shell, and a screw scraper is installed at the outer end of the centrifugal dehydration tank in the radial direction to move the rice grains in the axial direction along the peripheral wall of the centrifugal dehydration tank. A dehydration duct chamber for ventilation for evaporative dehydration is installed between the shell and the centrifugal dehydration tank.

The centrifugal dewatering tank has a draining part that surrounds the outer periphery of the screw scraper and has a large number of through holes that cannot allow rice grains to pass through, and has a starting end that is the axial end of the peripheral wall inside. A water supply section that discharges polished rice toward the starting end, and a water supply section that discharges water to the starting end are provided.

The screw scraper is arranged to move the rice grains from the starting end to the end of the peripheral wall of the centrifugal dehydration tank, and the scrubber dehydration dryer is provided with a collection section that collects unwashed rice from the end of the peripheral wall of the centrifugal dehydration tank. A washing-free rice manufacturing device characterized by:

15. The washing-free rice manufacturing apparatus according to item 14, characterized in that a rinsing water supply section for discharging water is disposed in an intermediate portion of the screw scraper.

16. The washing-free rice manufacturing apparatus according to items 14 and 15, characterized in that a ventilation duct corresponding to the ventilation dehydration duct chamber is inserted into the centrifugal dehydration tank from above.

17 Items 14 and 15, characterized in that the ventilation dehydration duct chamber is divided into multiple stages, and a dehydration duct is provided in each stage.
16. The apparatus for producing wash-free rice according to item 16.

18 The centrifugal dehydration tank can be placed vertically, horizontally, or diagonally in items 14, 15, and 16.

The apparatus for producing wash-free rice according to item 17.

19 Item 14, characterized in that the starting end of the draining part of the centrifugal dewatering tank is provided with a blind part in which no through hole is made.

The washing-free rice manufacturing apparatus described in Items 15, 16, 17, and 18.

20 Items 14 and 15, characterized in that a brush part for collision buffering is provided at the starting end of the screw scraper...
~...The washing-free rice manufacturing apparatus according to item 19.

21 Items 14 and 15, characterized in that the water supply unit and the water supply unit are integrated so that water and rice are mixed during supply.
. . . The washing-free rice manufacturing apparatus according to item 20.

The washing and dehydrating dryer in the washing-free rice production apparatus described in Items 2214, 15... to 21 includes a steam separator for recovering washing water from the washing and dehydrating dryer, and a pH of the washing water. The present invention resides in an apparatus for manufacturing rice without washing, which is combined with a pH regulator for adjustment.

``Operation'' The centrifugal dehydration tank is driven to rotate so as to generate centrifugal force that pushes the rice grains supplied inside in a radial direction.

Polished rice and water discharged into the centrifugal dehydration tank from the rice supply section and the water supply section are mixed and pushed by centrifugal force to a screw scraper on the outer periphery of the centrifugal dehydration tank. When the rice supply section and water supply section are integrated, the mixture is mixed inside the resupply section.

The mixture of polished rice and water that has reached the outer periphery of the centrifugal dewatering tank reaches the starting end of the screw scraper, where it is violently impacted by centrifugal force and the rotating screw scraper, and moves like a turbulent flow.

Repeated scattering and cleaning progresses.

When a screw scraper is provided with a brush at the base, the impact is buffered when it hits rice grains, thereby preventing the occurrence of cracked rice grains and deterioration of quality. In addition, in the case where a blind part is provided at the starting end of the draining part, a mixed state of water and rice is created there, and the water and rice come into effective contact to sharpen the rice.

The above is a washing process in which water is added to polished rice, mixed and stirred.

The mixture of water and rice is conveyed to the end of the colander by a screw scraper, and is dehydrated and dried by drawing water out through the holes of the centrifugal dewatering tank.

The rice grains, which are being moved while being dehydrated and dried, are sprayed with water from a rinsing water supply section at an intermediate section, and the aliuron residues and other impurities removed by the washing are washed away.

While the rice grains are moving through the centrifugal dehydration tank, a dehydration duct installed between the shell and the centrifugal dehydration tank removes air from the centrifugal dehydration tank, and the rice grains are evaporated and dehydrated.

The screw scraper moves the rice grains from the beginning to the end of the draining section of the centrifugal dehydration tank, and at the end, the rice grains are sufficiently dehydrated and dried through evaporative dehydration.

This is a dehydration process in which the water content of the washed rice grains is dehydrated to a range where the increase in water does not exceed 1%.

The processing time up to this point depends on the rice to be processed.It is about 30 seconds or less at room temperature, and the operating conditions for each process are such that the rice grains can be dehydrated to an extent that does not increase the moisture content by more than 1%. is set.

If the water temperature is low, the processing time will be longer than 30 seconds.

The unwashed rice from which alliuron residue has been removed from the polished rice is collected from the collecting section at the end of the draining section of the centrifugal dehydration tank, packaged in bags, etc., and then supplied to the market.

"Example" Hereinafter, one embodiment of the present invention will be described based on the drawings.

1 to 5 show a washing/dehydrating/drying machine 10 according to an embodiment of the present invention.

The dehydration dryer 10 has a rotatable centrifugal dehydration tank 30 installed in the a body 20, and the centrifugal dehydration tank 30 is configured to move the rice grains in the axial direction along the outer edge of the centrifugal dehydration tank 3o in the radial direction. Screw scraper symmetrically to the end within 30.40
A dehydration duct chamber 25 for evaporative dehydration is installed between the shell body 20 and the centrifugal dehydration tank 30.

The shell body 20 has a bottom plate 21 provided with a bearing portion 22 for pivotally supporting the centrifugal dehydration tank 3o, an outer plate 23 and a built-in centrifugal dehydration tank #a.
A dehydration duct chamber 25 is located in the space between the centrifugal dehydration tank 30 and the centrifugal dehydration tank 30.
It is formed to wrap around.

The dewatering duct chamber 25 has partition plates 26a and 26b.

It is partitioned into a plurality of chambers by 26c, and each chamber is provided with an air exhaust duct 27, 27, etc. Air inlets 28 for feeding drying air into the centrifugal dehydration tank 30 are provided corresponding to the air exhaust ducts 27, 27, . . . .

The centrifugal dehydration tank 30 is fixed to a drive shaft 30a rotatably fitted to the bearing portion 22 of the shell body 20 or to a bottom plate 32, and the drive shaft 3
Screw lever 40 symmetrically about 0a.
40 is arranged, and the draining part 3 wraps around the side wall 31 and the outer circumference of the screw scraper 40 at the end of the centrifugal dewatering tank 30.
It has an oval cross section of 3°33.

The ice cutting section 33 is provided with a large number of through holes that cannot allow even rice grains to pass through. However, a blind part 34 is formed at the starting end of the draining part 33, which is the lower part in FIG. 1, without opening a through hole.

Inside the centrifugal dewatering tank 30, there is a receiving cylinder 3 at the center of the bottom plate 32.
5 is erected and rice water is supplied from the lower end of the receiving cylinder 35 to the starting end which is the axial end of the draining part 33? i? 3a and 36 extend symmetrically in substantially radial directions, and a screw scraper 40
It opens in the tangential direction. Receiving port 35a of receiving cylinder 35
A washing water discharge pipe 11 and a water discharge pipe 12 are connected to.

The receiving cylinder 35 and the rice water supply pipe 36 constitute a rice supply section that discharges rice to the starting end of the draining section 33 of the centrifugal dewatering tank 30, and a water supply section that discharges washing water.

The rice water supply pipe 36 is oriented in the forward direction with respect to the rotating direction of the screw scraper 40 and has an angle in a direction that lags behind the peripheral speed of the screw scraper 40, so that the relative speed of the rice grains to the outer periphery of the screw scraper 40 is controlled. It is set to become smaller.

A rinsing water supply pipe 37 is installed in the drive shaft 30a of the centrifugal dewatering tank 30.
is formed and split into two in the centrifugal dehydration tank 30, and the rinse water discharge pipe 38, 38 or the middle of the drain part 33 of the centrifugal dehydration tank 30? B and the water supply pipe 37. The rinse water discharge pipe 38 constitutes a rinse water supply section.

The screw scraper 40 is arranged to move the rice grains from the starting end of the draining section 33 of the centrifugal dewatering tank 30 to the terminal end, which is the upper end in FIG. 1, and a brush section 41 for collision buffering is provided at the starting end. .

As seen in FIG. 5, the screw scraper 40 is arranged to be rotationally driven by a driving pulley 42 fixed to the drive shaft 30a.

Auxiliary pulleys 43, 43 with belts wrapped around them are arranged symmetrically with the drive boot 42, and the auxiliary pulleys 43, 43
A transmission pulley 43a integrated with.

43b and drive pulleys 44, 44 of the screw scraper 40.40 are connected by a belt, so that the screw scraper 40.40 rotates at a reduced speed relative to the rotation of the centrifugal dewatering tank 30.

Disc-shaped partition plates 45a, 45b, and 45c supported by support rods 46 and 46 installed between the bottom plate 32 and the top plate 32a are fitted and fixed to the centrifugal dewatering tank 30, and the partition plates 45a, 45b.

The outer edge of 45c is the partition plate 26a, 26 of 25 of the shell 20.
b and 26c overlap with a slight gap.

A collecting section 50 is provided at the upper end of the shell 20 to collect unwashed rice from the end of the draining section 33 of the centrifugal dewatering tank 30.

An inclined receiving plate 51 for receiving rice grains discharged from the rice grain outlet 39a between the lid plate 39 of the centrifugal dehydration tank 30 and the upper end of the draining section 33 is provided, and the receiving plate 51 and the lid plate 24 of the shell body 20
A recovery channel 52 is formed between the two.

A cushion damper 53 is provided on the outer periphery of the recovery channel 52 in the radial direction to catch the scattered rice grains, and a cushion damper 53 is provided at the bottom of the recovery channel 52 so as to be rotatable on a rice grain extraction souffle lever 54 or a roller 54a. ing. Rice grain removal souffle lever 54
There is one collection port 55 facing a part of the area.

Next, the operation of the dehydration/drying fi10 will be explained.

In the centrifugal dehydration tank 30, a drive shaft 30a is rotationally driven by an overseas drive source, and rotates to generate a centrifugal force that presses the rice grains supplied therein against a colander 33.
The rotational driving force of the driving pulley 42 fixedly installed at 0a is transmitted from the auxiliary pulley 43°43 to the transmission pulleys 43a, 4 integral with it.
3b to drive pulleys 44, 44, and the screw scrapers 40 and 40 rotate at a reduced speed relative to the rotation of the centrifugal dewatering tank 30.

Washing water is discharged from the washing water discharge pipe 11, and the water discharge pipe 12
Polished rice is discharged from the receiving cylinder 35, which serves as a rice supply section and a water supply section. Polished rice and water are mixed in the rice water supply pipe 36 and discharged toward the brush part 41 at the starting end of the screw scraper 40 corresponding to the starting end of the draining part 33 of the centrifugal dewatering tank 30.

The mixed polished rice and water discharged into the centrifugal dehydration tank 30 are pushed to the outer periphery of the centrifugal dehydration tank 30 by centrifugal force.

At this time, the water and rice are discharged from the rice water supply pipe 36 due to rapid acceleration due to centrifugal force, but the water and rice are discharged in the forward direction at an angle of inclination to the circumferential speed of the screw scraper 40. The rice does not violently collide with the starting end of the scraper 40 and further collide with the colander 33, thereby preventing the rice from being damaged by collision with the metal body.

The mixture of polished rice and water that has reached the outer periphery of the centrifugal dewatering tank 30 reaches the starting end of the screw scraper 40, where it is violently impacted by the centrifugal force and the screw scraper 40 that is being driven to rotate, and moves like a turbulent flow. The cleaning progresses through repeated splashing, rubbing against each other, and being hit by water.

It buffers the impact when the brush part 41 at the base of the screw scraper 40 hits the rice grains, and prevents the rice grains from cracking and quality deterioration due to excessive impact. In a blind part 34 provided at the starting end of a draining part 33 of a centrifugal dewatering tank 30, water does not drain out, and a mixture of water and rice stays, effectively washing away Aliuron and extracting and washing.

The above is a washing process in which water is added to polished rice, mixed and stirred.

The mixture of water and rice is conveyed to the end of the draining section 33 by the screw scraper 40, and is dehydrated and dried by drawing out the water through the through holes of the centrifugal dewatering tank 30.

The rice grains moving while being dehydrated and dried are sprayed with water from the rinsing water discharge pipe 38, which serves as the rinsing water supply section, in the middle of the drain section 33 of the centrifugal dehydration tank 30, and the aliuron residues and other particles are removed by washing. The impurities are rinsed away again. At this point, the moisture content of the rice has increased.The moisture content of the rice at this point is 2~
Operate so that it is 3%.

While moving in the centrifugal dehydration tank 30, the rice grains move through the centrifugal dehydration tank 3.
It rises as it is pressed against the draining section 33 of 0. Air for evaporation and drying is sent into the centrifugal dehydration tank 30 from the air inlet 28, and the air discharge duct 27 is in the dehydration duct chamber 25 arranged between the shell body 20 and the centrifugal dehydration tank 30.
．． 27 continues to remove air from the centrifugal dehydration tank 30, and air with adjusted relative humidity passes through the holes in the draining section 33 and is evaporated and dehydrated between the rice grains in the centrifugal dehydration tank 30. . The drying air must be free from flames.

Rice grain or centrifugal dehydration tank 3 using screw scraper 40
Both centrifugal dehydration and evaporative dehydration work while the rice grains are moved from the start end to the end of the draining section 33, and at the rice grain outlet 39a at the end, the rice grains are sufficiently dried by evaporative dehydration.

The unwashed rice from which Aliuron residue has been removed from the polished rice is discharged from the rice grain outlet 39a at the end of the draining section 33 of the centrifugal dewatering tank 30 and recovered from the recovery section 50.

The rice grains thrown out from the rice grain outlet 39a by centrifugal force hit the cushion damper 53, fall on the rice grain take-out souffle bar 54 and come to rest, and are further collected and discharged from the collection port 55 to be collected. Afterwards, it will be packaged in bags and other packaging before being supplied to the market.

This is a dehydration process in which the water content of washed rice grains is dehydrated to a level that does not exceed 1%.

The processing time up to this point is 30 seconds or less depending on the rice to be processed, and the rotation speed, suction air volume, and relative Operating conditions for each process, such as humidity, are set.

In the end, in order to remove Aliuron residue from milled rice and make it into wash-free rice that can withstand practical use, it is necessary to carry out a washing process in which water is added to the polished rice and mixed and stirred, and a dehydration process that is carried out at the same time or immediately after this washing process. The conditions are set according to the properties of the rice to be combined and symmetrical, and the water content of the washed rice grains is increased.
The goal is to process the amount within a range that does not exceed %.

The entire process takes less than 30 seconds depending on the rice being processed.

In other words, this means not over-soaking the rice with water. After being soaked in water excessively, it will lack taste no matter how you dehydrate and dry it.

In addition, simply mixing with water and stirring may not be able to sufficiently wash away the Aliuron residue, so it is effective to provide a rinsing step after the washing step to rinse off the deposits by pouring water. It also saves a lot of water economically.

For dehydration of rice grains, it is effective to use both centrifugal dehydration and evaporative dehydration.The first dehydration step using centrifugal force increases the thickness of the water adhering to the rice grains by 10%. The dehydration step (52) by evaporation may be carried out to a certain extent so that the moisture content of the rice grains increases by no more than 1%.

The second dehydration step by evaporation is non-heated evaporation, at a water temperature of about 10 to 25°C and an atmospheric relative humidity of 40 to 70%.
If it is done within 10 to 30 seconds, the taste of the rice grains can be preserved.

Also, if too much water is added, it will cause an excessive increase in moisture content, so it is important to avoid
~1000 times. Furthermore, if the wood to be added is prepared to be slightly acidic, it will be possible to easily dissolve the 7-liuron residue, and it will be possible to remove the 7-liuron residue effectively in a short period of time, and it will also require less mechanical auxiliary cleaning. There is an advantage.

In order to maintain the deliciousness of rice grains, it is necessary to extract and remove alliuron residues on the surface of polished rice, and to extract and remove alliuron residues on the surface of rice grains.
It is necessary to adjust the time and operation of each process to the extent that the rows of layered starch composite granules are well-organized. It was formed.

The system consists of a combination of a steam/water separator 4i113 that collects washing water from the washing/dehydrating/drying a10 and a PH adjustment model 4 that adjusts the pH of the washing water.
Filtration to purify the water collected in step 3 4115. Adjustment liquid reservoir 14a that sends acidic components to the PH adjuster 14, cleaning liquid pump 1
6. Air conditioner for relative humidity adjustment17. Air blower 17a, final conditioner 1B, product tank 19. This is a combination with a fresh water tank 19a.

In the above system, the washing water is circulated with its pH adjusted,
Evaporative dehydration is performed by blowing air from an air blower 17a, and humidity is controlled by an air conditioner 17. The final conditioner 18 can adjust the moisture content to about ±0.1%.

The product tank 19 is a hopper, and stores the unwashed rice for packaging such as bagging.

Now, when we look at the changes in the properties of the rice grains after washing, we see that the outermost surface of the starch grain alignment has become rough and uneven, and the film of viscous aliuron residue that coated that surface has also disappeared. 0 degrees is 3 to 10 degrees, and in some cases it's even higher.

If the temperature rises by 10 degrees or more, this is because deep cracks caused by excessive transpiration during the transpiration process cause diffuse reflections, causing the temperature to rise abnormally to 0 degrees.

In addition, the friction coefficient is extremely small, and one of them, the static repose angle, is about 10 degrees smaller.

On the other hand, since the viscous film that coated the skin has been removed, the impact stress is weak and it is so brittle that it is partially bruised by impacts of 3.5 G or more. In other words, it is extremely susceptible to cracking, chipping, and scratches.

Also, due to the synergistic effect of these two, the rice itself is in a state where it is immediately powdered.

As explained above, it is not the flour itself, but the flaws in the M powder composite grains or the broken rice grains that have come off, which deteriorates the taste, and it is necessary to handle the rice in a cylindrical shape as much as possible.

It goes without saying that the centrifugal dehydration tank can be put to practical use in any of the vertical, horizontal, or diagonal positions, and the blind part provided at the starting end of the draining part of the centrifugal dehydration tank can be installed as necessary. The same applies to the collision-absorbing brush portion provided at the starting end of the scraper. The water supply section and the water supply section may be separate units, and is it effective to make the washing water acidic?

May be neutral.

"Effects of the Invention" According to the method and apparatus for producing wash-free rice according to the present invention, the rice grains can be washed with water in a short time and dehydrated to prevent the rice grains from being damaged. Providing unrinsed rice with a good shelf life at a low price makes it possible to provide an innovative product to the distribution process.

[Brief explanation of the drawing]

Each figure shows an embodiment of the present invention, and FIG. 1 is a longitudinal cross-sectional view of a rice-free rice manufacturing apparatus, FIG. 2 is a cross-sectional view of a centrifugal dewatering tank, FIG. 3 is a plan view, and FIG. The figure is a front view of the inside of the centrifugal dehydration tank, Figure 5 is a plan view of the drive mechanism of the screw scraper, Figure 6 is a conceptual block diagram of the manufacturing equipment system, Figure 7 is a front view of general polished rice, and Figure 8 is also a cross-sectional view,
Figure 9 is an enlarged cross-sectional view of part ■ in Figure 7, Figure 1θ is a partial enlarged cross-sectional view of polished rice, Figure 11 is a partial enlarged cross-sectional view showing the state of damage in the part shown in Figure 1O, Figure 12 is a graph showing the soaking time of rice in water, Figure 13 is a graph showing the relationship between the thickness of the water film on the surface of rice grains after washing and the subsequent treatment time, and Figure 14 is a graph showing the water temperature from 0 to 3°C. A graph showing the relationship between the water content after washing and the processing time when the water content is low.
The mlS diagram is an explanatory diagram of rice grains washed under poor processing conditions. 10... Dehydration dryer 11... Washing water discharge pipe 1
2... Rice discharge pipe 20-... Shell body 25... Dehydration duct chamber 30... Centrifugal dehydration tank 30a... Drive shaft 32... Bottom plate 33... Draining part
34... Blind part 35-... Receiving tube 36-...
Rice water supply pipe 37--Water supply pipe 38--Rinse water discharge pipe 39 a-Rice grain outlet 40--Screw scraper 41--Brush portion 50--Recovery portion 52--
・Recovery channel 53--Cushion damper 54--Rice grain extraction souffle bar Fig. 2

Claims (1)

[Claims] 1. A washing step in which water is added to polished rice, mixed and stirred, and the washing step is carried out at the same time or immediately after the washing step until the water content of the washed rice grains does not increase by more than 1%. Depending on the rice to be processed, all processes can be carried out in the first step.
A method for producing wash-free rice, characterized in that the process is carried out in a short time without allowing water to penetrate below the rows of layered starch composite grains. 2. A washing process in which water is added to polished rice and mixed and stirred, a rinsing process in which water is poured after the washing process to wash away deposits, and the washing process and the rinsing process are carried out at the same time or immediately after, and the washed rice is washed with water. The process includes a dehydration process in which the grains are dehydrated to the extent that the increase in water content does not exceed 1%, and depending on the rice being processed, the entire process can be carried out for a short period of time to prevent water from penetrating below the rows of starch composite grains in the first layer. A method for producing wash-free rice, characterized in that: 3 When the water temperature of the washing water is about 10 to 25 degrees Celsius, the processing time for which the increase in moisture contained in rice grains does not exceed 1% is within about 10 to 30 seconds depending on the rice being processed. The method for producing wash-free rice according to claim 1 or 2, characterized in that: 4. When the washing water is cold water with a temperature of about 0 to 5 degrees Celsius, the processing time until the increase in moisture contained in the rice grains does not exceed 1% is within about 60 seconds depending on the rice being processed. The method for producing wash-free rice according to claim 1 or 2, characterized in that: 5. A washing process in which water is added to the polished rice, mixed and stirred, a rinsing process in which water is poured after the washing process to wash away deposits, and a first dehydration process using centrifugal force is carried out simultaneously with the washing process and the rinsing process. and a second dehydration step by evaporation, which is performed simultaneously or immediately after the washing step and the rinsing step, and dehydrates the washed rice grains to a range where the increase in water content does not exceed 1%. A method for producing wash-free rice, characterized in that, depending on the rice, all processes are carried out in a short time so that water does not penetrate deeper than the first layer of starch composite grains. 6 The first dehydration step using centrifugal force is carried out until the film thickness of water adhering to the rice grains is approximately 10 μm, and the second dehydration step using evaporation is performed until the water content of the rice grains increases by no more than 1%. The method for producing wash-free rice according to claim 5, characterized in that the method is carried out as follows. 7 The first dehydration step by centrifugal force is carried out until the moisture content of the rice grains increases by about 2.5%, and the second dehydration step by evaporation is carried out until the moisture content of the rice grains increases by no more than 1%. 6. The method for producing wash-free rice according to claim 5. 8 The second dehydration step by evaporation is non-flame thermal evaporation, and the water temperature is about 10-25°C and the relative humidity of the atmosphere is 40-70°C.
%, the time for which the increase in moisture does not exceed 1% is 1
Claim 5, characterized in that the time is within about 0 to 30 seconds.
6. The method for producing wash-free rice according to 7. 9 The water used is 1 of the aliuron attached to the rice grains.
Claim 1 characterized in that it is about 00 to 1000 times
, 2... to 8. The method for producing wash-free rice as described in 8. 10. The method for producing wash-free rice according to claims 1, 2, . . . , 9, wherein the water used is prepared to be slightly acidic. 11. Claim 1, characterized in that each step is adjusted to such an extent that alliuron residues on the surface of the polished rice are removed and the first layer starch composite grain arrays on the surface of the rice grains are arranged.
, 2... to 10. The method for producing wash-free rice. 12.Claims 1 and 2, wherein the polished rice has a moisture content that can withstand indoor storage at room temperature and humidity, and the residual amount of aliuron residue, which is an ingredient that affects the flavor of rice, is 2 g or less per 1000 g of polished rice.
~...11. The method for producing wash-free rice according to 11. 13. Wash-free rice characterized by comprising a rotationally driven centrifugal dehydration tank, a conveying means for moving the rice grains in the axial direction along the peripheral wall of the centrifugal dehydration tank, and an evaporative dehydration means for evaporating the rice grains while conveying them. manufacturing equipment. 14 A centrifugal dehydration tank that can be rotated is installed in the shell, and a screw scraper is installed at the outer end of the centrifugal dehydration tank in the radial direction so as to move the rice grains in the axial direction along the peripheral wall of the centrifugal dehydration tank. , a ventilation dehydration duct chamber for evaporative dehydration is installed between the shell body and the centrifugal dehydration tank; The interior includes a rice supply section that discharges polished rice toward the starting end, which is the end in the axial direction of the peripheral wall, and a water supply section that discharges water to the starting end. The screw scraper is arranged to move the rice grains from the starting end to the end of the peripheral wall of the centrifugal dehydration tank, and a collecting section is provided for collecting unwashed rice from the end of the peripheral wall of the centrifugal dehydration tank. A no-rinse rice manufacturing device characterized by being equipped with a washing, dehydrating and drying machine. 15. Claim 1, characterized in that a rinsing water supply section for discharging water is disposed at an intermediate portion of the screw scraper.
4. The washing-free rice manufacturing apparatus according to 4. 16. The rice-free rice manufacturing apparatus according to claim 14, wherein a ventilation duct corresponding to the ventilation dehydration duct chamber is inserted into the centrifugal dehydration tank from above. 17. Claim 14, characterized in that the ventilation dehydration duct chamber is divided into a plurality of stages, and a dehydration duct is provided in each stage.
15, 16. The washing-free rice manufacturing apparatus described in 15 and 16. 18. The washing-free rice manufacturing apparatus according to claim 14, 15, 16, or 17, wherein the centrifugal dehydration tank is placed vertically, horizontally, or diagonally. 19. Claims 14, 15, 1, characterized in that a blind portion in which no through hole is formed is provided at the starting end of the draining portion of the centrifugal dewatering tank.
6, 17, 18. The washing-free rice manufacturing apparatus. 20 Claims 14, 15, etc., characterized in that a collision buffering brush portion is provided at the starting end of the screw scraper.
. . . 19. The washing-free rice manufacturing apparatus according to 19. 21 Claims 14 and 15 characterized in that the rice supply section and the water supply section are integrated so that water and rice are mixed during supply.
. . . 20. The washing-free rice manufacturing apparatus according to 20. 22 The washing and dehydrating dryer in the washing-free rice manufacturing apparatus according to claim 14, 15...21, includes a steam separator for recovering washing water from the washing and dehydrating dryer, and a pH of the washing water.
This is a rice-free manufacturing device that is combined with a PH regulator.