JPH04222566A - Production of packed instant boiled rice - Google Patents

Abstract

PURPOSE:To unnecessitate to wash rice with water and immerse the rice in water without causing the putrefaction of the rice and without lowering the taste and quality of the rice. CONSTITUTION:Raw rice is washed with finely air-bubbled water to reduce microbes in the raw rice, packed and thermally sterilized to provide packed instant boiled rice which does not putrefy and does not lower the taste and quality thereof and which does not require to wash the rice with water and immerse the rice in water before boiled.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing so-called packaged ready-to-cook rice, which allows rice to be cooked immediately after opening the package and without washing or soaking the rice in water.

0002

[Prior Art] Conventionally, as a method for producing quick-cooked rice similar to this type of production method, glutinous rice is soaked in water for a short period of time to bring the moisture content of the glutinous rice to about 30 to 45%. A method is known in which partially pregelatinized rice is prepared by steaming and at least the surface portion is pregelatinized, and then this is dried at a temperature of about 75° C. or lower (Japanese Patent Laid-Open No. 52-61249). Quick-cooked rice prepared using this method absorbs water a little faster during cooking than when water is added to raw rice, and the time from soaking in water to finishing cooking can be shortened accordingly. Compared to dried rice made by drying, it has the advantage that the rice is not sticky after absorbing water and drying.

[0003] In addition, water-soaked rice that has been soaked in water for about 1 to 10 hours can be made into a viscous state (starch dispersed in water and made viscous by heating, modified starch, rice flour, or even a gum substance dispersed in water). Fill the container and seal it for 10 minutes.
A method of heat sterilization at a temperature of 0° C. or higher is also known.

Furthermore, in order to eliminate soaking time, uncooked rice that is not soaked in water is coated with a viscous liquid either as is or after washing, so that the total moisture content of the mixture of uncooked rice and viscous liquid is about 38. An improved method in which the ratio is adjusted to ~47% has also been proposed (Japanese Patent Publication No. 57-46824).

On the other hand, in Japanese Patent Publication No. 57-44302, moisture is added within the limit of occurrence of shell cracking, taking into account various points such as water absorption and expansion rate of rice grains, and improves storage stability, rice milling efficiency,
A moisture addition method has been proposed to correct the moisture content of rice grains in order to obtain moisture-added rice with improved palatability and almost no shell cracking. A circulation path is formed for rice grains flowing from the lower part to the grain frying device and from the grain lifting device to the top of the tank, and a moisture addition device is installed in this circulation path, and the moisture addition device adds 0.233% per few seconds to the circulating rice grains. It discloses a method in which the water content of rice grains increases by 0.67% or less per hour by adding the following water.

[0006]

[Problem to be solved by the invention] JP-A-52-6124
Quick-cooked rice made using the production method disclosed in Publication No. 9 does not become sticky due to the softening of the rice, but because the water content decreases due to drying, it is made by adding water directly to raw rice and cooking it. Compared to boiled rice, it has lost its elasticity, has a much inferior texture, and has a lack of luster.

[0007] Water immersion The method of coating water with a viscous liquid, filling it in a container, sealing it, and heating and sterilizing it at a temperature of 100°C requires water immersion for about 1 to 10 hours, so there is a problem in that extra time is required.

[0008] The method for producing packaged quick-cooked rice disclosed in Japanese Patent Publication No. 57-46824 does not require time-consuming soaking in water, so the preparation work is simple, and the structural integrity of starch is reduced during heat sterilization. Because there is almost no breakage, when rice is cooked with water added, it becomes as elastic and shiny as rice obtained by directly cooking raw rice, and there is no risk of spoilage even if it is left at room temperature for several months. However, it requires a separate preparation of a viscous liquid made of starch, etc.Also, although it may be effective for quickly cooking glutinous rice, it does not require washing of regular rice. It is not believed that the instant cooking method necessarily yields rice with a similar texture.

[0009] Originally, raw rice was distributed with a moisture content of less than 16% because it was easily perishable, and it was essential to wash the rice and soak it in water during cooking. In order to solve these problems, rice has been developed that does not require washing or soaking in the conventional techniques mentioned above and other generally known methods, but it is difficult to shorten the cooking time or to reduce the cooking time. This is a method whose main purpose is only for quick cooking, and it does not necessarily take the inherent flavor of rice into consideration, so it is considered to be an unsuitable method to be applied to high-quality rice that takes advantage of its flavor. Raw rice originally has a high number of bacteria, so high moisture content rice that has been washed and soaked in water is easily damaged and cannot be distributed, so it is distributed in a dry state. Therefore, it was essential for users to wash the rice and soak it in water before cooking it.

[0010] The purpose of the present invention is to provide a method for producing instant-cooked rice of good quality, which reduces and sterilizes the fungi that cause spoilage in raw rice, and which does not cause spoilage or deterioration of taste quality. shall be.

[0011] In view of the above-mentioned problems, the present invention provides efficient instant-cooked rice that does not require any special mixing liquid, has a simple process, and maintains almost the same quality of cooked rice as when the rice is washed before cooking. The purpose is to provide a manufacturing method for.

0012

[Means for Solving the Problems] The present invention provides a package configured to wash uncooked rice with fine bubble water to reduce fungi in the uncooked rice, dehydrate it, and then sterilize it by heating to obtain ready-cooked rice. This is a method for producing instant-cooked rice.

[0013]

[Example] First step Raw rice is washed with fine bubble water.

In the test example, 3 kg of commercially available Koshihikari rice was placed in a plastic bucket and washed with water. Washing was carried out for 5 minutes while changing the water once every minute and stirring gently by hand. The water used for washing was tap water and dispersion water in which air was finely suspended using an ejector. After washing, the water was dehydrated, and a portion of this was taken into a sterile resin bag and used as a sample for bacterial count measurement. did. Add 1 g of this sample to 50 cc of sterile saline in a sterile container.
The solution was taken into a container and triturated for 5 minutes in a stomacher, and used as a bacterial test solution. 1 ml of this was cultured on a standard agar medium at 30° C. for 2 days, and the number of colonies developed was taken as the number of bacteria in the washed rice. This was repeated five times, and it was confirmed that the number of bacteria was definitely reduced during the bubble water washing process.

[0015]

[Table 1]

[0016] In this way, just as the fine air bubbles existing in water grind the propeller of a ship, when the abrasive power of the fine air bubbles in water was applied to raw rice, the number of bacteria in the rice was reduced to 10 when washed with water.
It became possible to reduce the weight to about 2/g. By simply applying appropriate packaging conditions and low-temperature distribution conditions,
It can be kept for about two weeks. However, in the summer
When the temperature reaches the ℃´ range, rice can only be stored for about 3 days with this bacteria count. In other words, although it was possible to reduce the number of bacteria through the bubble water washing process, it is necessary to reduce the number of bacteria per gram to 0 to 0.1 in order to further stabilize the quality during the distribution period. Therefore, the next second step is essential.

After washing the rice in the second step, the rice grains are dehydrated until approximately 14 to 15% of the adhering water is attached to the rice grains, and then packaged, and dry sterilized while retaining the adhering water to obtain ready-cooked rice.

[0018] In a test example in which the sterilization method was investigated although it did not affect the quality of the rice, 300 g of dehydrated rice was injected into KN.
The sample was collected in a packaging material, and the heating conditions were 1 in 3 areas of 50℃', 60℃', and 70℃' under the packaging conditions of vacuum packaging and air-containing packaging.
Table 2 shows the results of comparing rice quality and sterilization status using two heating methods: hot water and air.

[0019]

[Table 2]

[0020] After washing the rice, soak it in tap water for 2 hours, put it in a dehydrator, immediately put it in a plastic bag, seal it, and heat it at 60°C for 1 hour. When the bacteria were examined after being kept in the container for 2 days, the occurrence of lactic acid bacteria was observed. Therefore, in order to slow down the temperature rise rate of the rice grains, suppress the growth of bacteria during the soaking process, and compensate for the lack of moisture, the rice grains are packaged with about 14 to 15% of water attached to the surface. We investigated the method of preserving in heated air, obtained Table 3, and compared the differences in cleaning methods in the previous process and the sterilization effects.

[0021]

[Table 3]

As a result, by heating and sterilizing the rice with about 14 to 15% of water attached, it was possible to prepare ready-to-cook rice as desired. It was also confirmed that in order to increase the effectiveness of dry sterilization, it is essential to reduce the number of bacteria using aerated water in the first step.

Furthermore, when the conditions for reducing the number of bacteria by drying were investigated, a remarkable bactericidal effect was shown at temperatures of 60°C' or above. Therefore, a heating temperature of around 60℃' is the optimal temperature that does not cause any structural changes to immediately cooked rice, and if you immediately cook the rice without washing it by just adding water, it will be the same as rice that is washed and cooked. It was confirmed that this was instant-cooked rice with elasticity, flavor, aroma, and luster.

[0024]

[Effects of the Invention] The present invention is constructed so that the uncooked rice is washed with fine bubble water to reduce the fungi in the uncooked rice, dehydrated, packaged, and heat sterilized to obtain ready-cooked rice. , there is no risk of spoilage or deterioration of taste quality, and there is no need to wash or soak the rice before cooking. A method for producing boiled rice can be provided.

Claims (1)

[Claims] [Claim 1] The method is characterized in that raw rice is washed with micro-bubble water to reduce fungi in the raw rice, dehydrated, packaged, and heat sterilized to obtain ready-cooked rice. Method for producing packaged ready-cooked rice.