JPH0238188B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing processed brown rice that can be cooked in the same manner as polished rice using a commonly used rice cooker and that is delicious to eat. In other words, brown rice is soaked in water or warm water, and then steamed. After steaming, the sugar layer of the brown rice is steamed by passing it between two rotating rolls while keeping it at a predetermined temperature and pressing it. This is a new method for producing processed brown rice that mainly forms multiple band-shaped cracks in the lateral direction. The surface of brown rice is surrounded by a pericarp, below which there is a seed coat, and inside that is the embryo and endosperm. The sugar layer is an aleurone layer on top of the pericarp, seed coat and endosperm.
White rice is the endosperm from which the sugar layer and embryo have been removed through refinement, and most of it is starch. The embryo and the sugar layer are rich in nutrients such as protein, fat, vitamins, and minerals, and the sugar layer also contains many useful fibers. Although brown rice is excellent in terms of nutrition, it has a sugar layer that not only has poor water absorption, but also the cooked rice grains are pressed down by the sugar layer and do not swell sufficiently, resulting in hard rice that is not widely used. The rice cooker I have now has the disadvantage that I can't cook it properly. Therefore, various processing methods have been invented for brown rice that can be cooked in the same way as commonly used rice cookers and polished rice without sacrificing the nutritional value of brown rice. For example, a processing method that expands brown rice to make the entire grain porous;
A processing method in which brown rice is overdried and rapidly cooled to create cracks in the sugar layer. By allowing only the sugar layer of brown rice to absorb water, removing the adhering water, and frying it on a heated metal plate and pressurizing it with a heated object. This is a method of creating cracks, etc. However, brown rice processed by these methods is simply made porous or has irregular cracks in the sugar layer with the endosperm not gelatinized, so when the rice is cooked, it bends through these cracks and the cooked rice grains Because the rice splits and disintegrates, it is difficult for the entire rice to have uniform softness, and the texture in the mouth is poor, such as texture and texture, and it cannot be said to be delicious. Therefore, the inventors completed the present invention as a result of repeated research on a new method for producing processed brown rice that not only allows rice to be cooked in the same manner as polished rice, but also allows the cooked rice grains to maintain their grain shape in the same way as polished rice. The present invention involves soaking brown rice in water to absorb water so that the moisture content of the brown rice becomes 22 to 35%, and steaming it with normal pressure or pressurized steam to gelatinize and soften the endosperm of the brown rice. Next, this steamed brown rice is kept at a specified temperature and 0.7
Forming a plurality of band-shaped cracks mainly in the lateral direction in the sugar layer of the steamed brown rice by passing it between two rotating rolls having a gap of about millimeters and pressing it, and further drying the pressed steamed brown rice. This is a method for producing processed brown rice characterized by the following. The manufacturing process of processed brown rice of the present invention will be explained below. After removing stones, milled rice, etc. from the raw brown rice, it is soaked in water to absorb water. The amount of water absorbed is
This varies depending on the means of steaming; in the case of pressure steaming, the water content may be about 22%, and immersion at a water temperature of 20°C for 2 hours or at 40°C for about 40 minutes is sufficient. In the case of normal pressure steaming, the moisture content is 25-35% and the water temperature is 50℃.
Soak for 1 hour at ~60°C. If the moisture content is too high or too low, steamed brown rice that is elastic and suitable for pressing cannot be obtained. Note that by circulating water or warm water during soaking of brown rice, dust adhering to the brown rice can be removed, eliminating the need for washing the rice during cooking. Steaming is carried out until the inside of the brown rice, that is, the endosperm, becomes gelatinized and softened, but in the case of normal pressure steaming (steaming using steam at 100℃), steaming is carried out for about 30 minutes. Pressure steaming
In this case, approximately 0.5Kg/cm ² is desirable, and it takes about 20 minutes. In the pressing step, the steamed brown rice is held at a predetermined temperature and passed through a gap between two rolls and pressed to form a plurality of band-shaped cracks mainly in the horizontal direction in the sugar layer of the steamed brown rice. In this case, the appropriate gap between the rolls is around 0.7 mm. If the gap is too narrow, the brown rice grains will be crushed or flattened, making it difficult for them to return to their granular form when cooked. If it is too wide, there will be few cracks in the sugar layer, and when rice is cooked, water absorption will be poor and swelling will be insufficient, resulting in hard brown rice. The temperature of the steamed brown rice during pressing has a bearing on how well it penetrates into the rolls, so it is desirable to keep it at 50°C or higher. In this case, the reason why belt-shaped cracks are formed mainly in the horizontal direction in steamed brown rice is that when the long axis of elastic brown rice that is kept at a predetermined temperature and is pressed with a roller, the long axis of the brown rice grain is It is extremely rare for the long axis to be pressed parallel to the rotation axis, and the long axis is inclined to either side and the inclined end is drawn into the roller first, causing a shift between the sugar layer and the endosperm. occurs, and as a result, the short axis intersects the long axis, i.e.
This is because band-shaped cracks are sequentially formed in the lateral direction of the sugar layer in relation to the roller. Drying is carried out to remove excess moisture and press steaming until the moisture content of brown rice reaches around 14%. A dryer that has good drying efficiency and prevents the sugar layer from peeling off due to friction between rice grains is suitable. The processed brown rice produced by the method of the present invention is produced by gelatinizing and softening the brown rice down to the endosperm and then steaming it, and then holding the steamed brown rice at a predetermined temperature and passing it through a gap between rolls and pressing it while it still has elasticity. Therefore, band-shaped cracks are formed mainly in the horizontal direction in the sugar layer of steamed brown rice, so water absorption during cooking is good as shown in Test Example 1 below, and as the endosperm swells due to heating. The cracks in the sugar layer open on average. Because of these characteristics, it is possible to cook only the processed brown rice of the present invention using a commonly used rice cooker in the same manner as for milled rice, and it is also possible to avoid inconveniences such as the rice losing its shape, and it can be mixed with polished rice. Even when rice is cooked, it swells in the same way as polished rice, resulting in good rice with almost no discomfort due to brown rice being mixed in. In addition, when cooking only processed brown rice, it is convenient because it can be cooked without adding water and soaking time. The method of the present invention will be explained in more detail with reference to Examples below. Example 1 Brown rice produced in 1982 (Koshihikari, moisture 15.0%)
1 kg was washed with water, immersed in room temperature water (22°C) for 2 hours to absorb water, and then drained using a centrifugal dehydrator. The weight of brown rice after draining was 1.10 kg (moisture 22.7%). Put this in an autoclave, 0.4Kg/cm ² ,
It was steamed at 107.5°C for 20 minutes. The weight of steamed brown rice is
It weighed 1.25Kg. Rotate the steamed brown rice at a constant speed 2
It was pressed through the gap (gap width 0.7 mm) between the book's smooth surface rolls. The pressed brown rice was dried in a hot air dryer at 100°C to obtain 990 g (moisture 14.2%) of processed brown rice in which many band-shaped cracks were formed mainly in the lateral direction in the sugar layer of the brown rice grains. Example 2 3 kg of brown rice, the same as that used in Example 1, was washed with water, soaked in warm water at 60°C for 1 hour to absorb water, and drained using a centrifugal dehydrator. The weight of brown rice after draining is
It weighed 3.73Kg and had a moisture content of 31.2%. This was placed in an autoclave and steamed at 100°C for 30 minutes.
The weight of steamed brown rice was 3.88 kg and the moisture content was 34.1%. This was pressed and dried in the same manner as in Example 1,
Similar to Example 1, brown rice grains weighing 2.95 kg (moisture 13.7
%) of processed brown rice was obtained. Test Example 1 10 g each of the processed brown rice of the present invention obtained in Example 1 and the control rice were immersed in water at 22° C., and the water absorption rate was measured over time. The results are shown in Figure 1. In FIG. 1, the water absorption rate of the processed brown rice obtained in Example 1, the water absorption rate of polished rice, the water absorption rate of commercially available processed brown rice A, and the water absorption rate of commercially available processed brown rice B, respectively. It is clear from FIG. 1 that the processed brown rice of the present invention has an extremely good water absorption rate. Test Example 2 The processed brown rice of the present invention obtained in Example 1 and the control rice were cooked, and the properties of the cooked rice were investigated. When cooking the sample, use an electric rice cooker (SHARP).
Using KS-O50P (Sharp Co., Ltd. product),
One cup of each sample was taken using the included cup, added with the indicated amount of water, left to stand for 30 minutes, and then cooked. After 15 minutes of stirring time, the weight of the cooked rice was weighed, and the value divided by the weight of 1 cup of each sample before cooking was taken as the weight increase rate. In addition, only white rice is 2
After rinsing ~3 times, add water to the indicated amount. The results are shown in Table 1.

[Table] Test Example 3 A rice cooking test was conducted on the processed brown rice of the present invention obtained in Example 2 in the same manner as in Test Example 1. As a result, the weight increase rate was 2.18, and the sensory evaluation of the processed brown rice was as good as that of Example 1. Further, when the processed brown rice obtained in Example 2 was weighed in the same manner as in Test Example 1, water was added, and the rice was immediately cooked without any soaking time, good brown rice was obtained in the same manner as above. Furthermore, 2 pieces of processed brown rice and 8 pieces of white rice obtained in the example were added.
When rice was mixed and cooked at the ratio of , both the processed brown rice and white rice turned out to be good, and there was no particular discomfort in the mouth due to the brown rice being dispersed in the white rice.

[Brief explanation of drawings]

FIG. 1 shows the water absorption rates of processed brown rice of the present invention and control rice.

Claims (1)

[Claims] 1 Soak brown rice in water until the moisture content of brown rice is 22-35%.
The brown rice is steamed using normal pressure or pressurized steam to gelatinize and soften the endosperm of the brown rice.Then, this steamed brown rice is held at a predetermined temperature and steamed into two sticks with a gap of around 0.7 mm. Production of processed brown rice characterized by forming a plurality of band-shaped cracks mainly in the lateral direction in the sugar layer of the forward steamed brown rice by passing it between rotating rolls and pressing it, and further drying the press steamed brown rice. Method.