JPS6331174B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing rice with improved taste. It goes without saying that the taste of rice is primarily based on the variety, place of origin, history, moisture content, pH, etc. of the brown rice, but what is important in the taste of rice is its stickiness and suppleness. In order to improve these, it is important to completely gelatinize the rice during cooking, and to do so, it is necessary to increase the moisture content of the rice grains to an average of about 30% down to the core of the rice grains.

Generally, when rice is soaked in water at room temperature, water absorption equilibrium is reached in about 1 hour, although there are some differences depending on the rice.
It typically exhibits an equilibrium moisture content of 26-32%. Regarding moisture absorption equilibrium, rice left in air at 75% RH (relative humidity) usually exhibits a moisture absorption equilibrium moisture content of 12 to 15%, and there are slight differences in the moisture absorption equilibrium value depending on the rice. Rice with a low moisture absorption equilibrium value also has a low moisture absorption equilibrium value.
This kind of rice has low bound moisture and adsorption energy, but this is because the moisture binding power of the starch that forms the rice particles is impaired, and the air that is stored in the cavities inside the rice particles is Bubbles inhibit water penetration, and even if the moisture content is the same (30%), such rice particles will have too much moisture on the outside and less moisture on the inside, and even when cooked, the outside will be too soft and the inside will be too soft. There is a tendency for some core to form in the rice, resulting in spots when cooked.

Therefore, the preferred method is that when rice is soaked in water,
After immediately reducing the pressure and degassing, the pressure is returned to normal pressure, water is absorbed, and the water is drained. With this method, the water is evenly distributed inside and out, and the cooked rice has a uniform softness and flavor. Increase. In this case, the draining step is necessary to make the adhering moisture uniform, and takes approximately 30 minutes to 1 hour. Depressurization, deaeration, and soaking rice have the effect of slowing down the aging process of rice.

It is said that rice loses 20 to 50% of the vitamins or amino acids contained on its surface when washed with water. In addition, rice with good flavor has a high amino acid content, so in order to improve the flavor and nutrition of rice with poor flavor, we use a depressurization and water soaking process to dissolve nutrients and flavor enhancers in the soaking water. It was discovered that delicious water-soaked rice can be obtained by adsorbing these ingredients.

Rice, which actually has 12% water, has a moisture content of 28±2
%, it is necessary to retain approximately 26% of the water, and it is understood that around 30% of the water must be absorbed before cooking to promote gelatinization down to the core of the cooked rice.

The amino acids in rice are mainly glutamic acid, but also contain glycine and alanine. Therefore, soaked rice containing a flavor improver can be obtained by dissolving sodium glutamate in water, soaking the rice, depressurizing it, deaerating it, and then absorbing water. Glycine and alanine have a sweet taste, help improve flavor, and have a buffering effect.
A similar treatment yields soaked rice with improved flavor. Normal rice has a pH of 6 to 7, but particularly flavorful rice is said to have a pH of 6.7 to 6.9. PH6.7
When the following types of rice are brought to a pH of 7.2 to 7.8, their stickiness increases, but the browning reaction of reducing sugars occurs, and the presence of protein produces an alkaline odor, which impairs the flavor of the cooked rice. Old rice has particularly high levels of reducing sugars due to the action of amylase. In such cases, adjusting the pH to 4.5 to 5 can restore flavor, suppress browning, and extend the storage time of flooded rice. In such cases, the pH can be adjusted with a buffer solution such as glycine, common salt, organic acids and their salts, and polymerized phosphates.

In addition, rice whose phytin has been broken down by the action of enzymes is
Contains Ca salt and Mg salt, which tends to make cooked rice hard. In such cases, chelating agents such as phytates extracted from rice bran, polymerized phosphates, etc. are dissolved in the soaking water. Then, by applying reduced pressure and soaking in water to uniformly distribute the rice into rice particles, rice with good flavor can be obtained.

In addition, in order to delay the aging of rice, the storage period of rice can be extended by soaking the rice in water to which a small amount of surfactant and sodium polyacrylate has been added, reducing the pressure, and adsorbing the rice.

Rice sometimes adsorbs off-flavors during storage and transportation, and the degassing and soaking in the present invention can remove off-odors, but it also dissolves odor-producing substances such as peptides containing glutathione and cysteine extracted from rice bran. When soaked, soaked rice containing flavor substances is obtained.

Example A: Wash 1 cup of rationed rice (moisture 13%, PH6.4, 168 g) with water and place the washed rice in a vacuum container. On the other hand, 6g/
Mix 13.6 g of acetic acid aqueous solution and 13.6 g of sodium acetate aqueous solution in a ratio of 3:2, take 150 ml of the mixture, add 1 g of sodium glutamate, 0.5 g of glycine, 0.2 g of alanine, 0.3 g of rice bran extracted peptide, and 0.001 g of thiamine hydrochloride. Comb it, add it to the same vacuum container, hold it under a vacuum of 700mmHgG for 10 minutes, and after the generation of small bubbles stops, return it to normal pressure, and at 16℃
Leave to absorb water for 1 hour, drain for 1 hour, and average the moisture to obtain soaked rice containing nutrients and flavor enhancers.

This soaked rice is prepared by adding 250 ml of water to adjust the water content and cooking the rice for 30 minutes, then cooking it for 15 minutes to obtain nutritious and delicious rice.

B. Wash 1 cup of rationed rice (moisture 12%, PH 6.0, 170g) with water and process this washed rice in the same manner as in section (a), but use water for soaking in addition to sodium hexametaphosphate.
0.1g, acidic sodium pyrophosphate (acid pyro) 0.05
g, further dissolve 0.1 g of cysteine hydrochloride 1aq.

C. Wash 1 cup of rationed rice (moisture 12%, PH 6.0, 171 g) with water and process this washed rice in the same way as in section A.
If you dissolve 0.1 g of sodium polyacrylate in addition to item (a) in the water for immersion, you can obtain rice with a long shelf life.

D. Add water-soaked rice obtained in sections A, B, and C to a thickness of 5 cm.
By sealing the rice in a plastic bag and sterilizing it in hot water at 76°C for 1 hour, soaked rice with better shelf life, rich in nutrients, and improved flavor is obtained.

This water-soaked rice is sanitary and has good flavor by simply controlling the amount of water and heating it unevenly.

Claims (1)

[Claims] 1. Raw rice is immersed in a slightly acidic room temperature aqueous solution containing nutrients and/or taste improvers in a pressure-resistant container, and air bubbles stored in cavities inside the raw rice are removed from the outside. After that, a slightly acidic room temperature aqueous solution containing the nutrients and/or taste improver is infiltrated into the cavity inside the uncooked rice to replace the released air bubbles. A method for producing flavor-improved rice, which is characterized in that the rice is returned to normal pressure to absorb liquid, and then drained to a predetermined moisture content. 2. The taste-improved rice according to claim 1, wherein the nutrients and/or taste improvers are selected from the group consisting of rice bran extracted phytate, alanine, thiaamine hydrochloride, hexametaphosphate, and polyacrylate. manufacturing method. 3 The moisture content in the raw rice after draining the water is 28±2
% of the taste-improved rice according to claim 1 or 2. 4. The pH of the aqueous solution containing the nutrients and/or taste improver is within the range of 6.7 to 6.9, the depressurization and holding time is 15 minutes at a maximum pressure of 700 mmHg, and the draining time is 1 to 6.9.
The method for producing taste-improved rice according to any one of claims 1 to 3, wherein the cooking time is 1.5 hours.