JPS6016560A - Production of packed cooked rice - Google Patents

Abstract

PURPOSE:To obtain cooked and packed rice free from stickiness, having high heat transmission, and suitable as CHAZUKE (a meal of rice and tea mixed), piraff, etc., by sealing rice containing a proper amount of water in a bag made of a synthetic resin film, etc., cooking the rice with steam, etc., and freezing and then thawing the product. CONSTITUTION:Polished rice is washed with water, usually heat-treated to convert the starch to alpha-form, washed again with water to remove the slime from the surface, adjusted to a proper water-content, and sealed in a bag made of e.g. a synthetic resin film. The rice is cooked e.g. with steam under pressure, cooled, frozen and thawed to obtain the objective cooked and packed rice.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing packaged cooked rice that is not sticky and has good heat conductivity for use in ochazuke and pilaf.

Cooked rice suitable for long-term storage is obtained by sealing raw rice with an appropriate moisture content in a bag made of synthetic resin film, etc., and heating it with steam or other means to cook the rice in the bag. This is known from Japanese Patent Publication No. 19862/1986 in the method for packaging cooked rice. Rice prepared using this method is
The rice grains turn into grains, become sticky, and form nodules, and the cooked rice retains its agglomerates even when it becomes cold and the sticky power of the rice grains decreases.

On the other hand, for rice for ochazuke and pilaf, each grain of rice must be separated. This is because if the rice for ochazuke and pilaf is in the shape of a lump, it will not heat through easily and will not be tasty.

Tokuko Sho 5 is a method for breaking up rice grains one by one.
The method for producing fluid cooked rice disclosed in Japanese Patent Publication No. 1-23574 and the method for producing instant ochazuke food disclosed in Japanese Patent Publication No. 52-46292 are known.

The former publication describes a production process in which cooled cooked rice of an appropriate thickness is conveyed completely continuously, and cooled high-pressure air is injected to the tip of the cooked rice, causing it to scatter and fall into the cooled atmosphere, and then collected. It's a method. That is, each grain of cooked rice is broken apart in a wind speed of 30 to 50 m/s.

However, in this method, the rice grains blown by strong winds of 30 to 50 m/s collide with the walls of the device and become car-shaped, resulting in poor yield and 30 to 50 m/s.
It has the disadvantage of requiring special equipment to provide a strong wind environment of m/s.

In the latter publication, the rice cooking process, sterilization process, cooling process,
After the aging step of converting alpha starch into beta, it consists of a rice grain separation step in which the rice grains are separated one by one by applying a mechanical impact using a means selected from squeezing, twisting, and beating.

That is, in the latter publication, the cooked rice grains that have formed into clumps are broken up by applying a mechanical impact. In this method, each grain of rice is broken up, but the shape of the rice grains may become flattened, or some parts may be missing.
It also has the disadvantage that it becomes wheel-shaped, resulting in poor yield.

The present invention solves this problem, that is, when breaking apart cooked rice grains one by one, the rice grains do not break and the yield is low. This is a type of packaged cooked rice in which rice with an appropriate amount of moisture is sealed in a bag and then heated with steam or other means to cook the rice inside the bag, which is then subjected to further freezing and thawing treatment after cooking. .

The steps of the present invention will be explained in detail below.

(1) Rice washing process Polished rice is washed and soaked in water, then drained to make raw rice.

(2) Raw boiling process Raw rice is steamed and heat treated for about 20 minutes to make it raw and the starch is α
become While washing the raw boiled rice with cold water, reduce the appropriate moisture content by 1.
The water content is adjusted to 45 to 200% to remove the glue-like slime and α-starch on the surface of raw boiled rice, and to absorb water.

(3) Packaging process Raw boiled rice with an appropriate amount of moisture after moisture adjustment is filled into a bag made of synthetic resin or the like, and the bag is sealed with some air added to prevent compression of the steamed rice.

(4) Rice cooking process Cook the rice in the bag by steaming and pressurizing at 120°C for about 10 minutes. At this time, the starch in the rice grains in the bag is gelatinized and cooked into clumps. It is sterilized at the same time.

Cool the bag naturally to 0-5°C in cold water, cold air, or in the refrigerator. After about a day of this cooling process, the α-starch changes to β-starch.
It becomes a starch and makes a preparation that accelerates retrogradation and separates easily.

The packaged cooked rice that has gone through the cooking and cooling steps is further subjected to the following treatment to easily separate each grain of rice.

(6) Freezing process Freeze the rice grains at below 0°C. ff1J As shown in Figure 1-2, before freezing, there were no cracks in the outer skin or inside of rice grain 1, as shown in Figure 1, but after freezing, as shown in Figure 2, the outer skin of rice grain 1, Internal cracks 2 occur and the hard tissue of the epidermis is damaged.

That is, when the moisture in rice grains freezes, the volume increases by approximately 11%, and this volume increase damages the epidermis.

(Force thawing step: By placing the rice in water at a temperature of 0°C or higher, or by allowing it to thaw naturally, the rice grains with damaged outer skins become separated one by one from the clump state.

As described above, in the present invention, rice having an appropriate amount of moisture is sealed in a conventional bag made of synthetic resin film, etc., and the rice is cooked in the bag by heating it with steam or other means. In packaged cooked rice, the α-starch on the surface of the rice grains forms a lump, making it unsuitable for products where each grain is separated, such as ochazuke or pilaf. However, in the present invention,
The above-mentioned drawbacks are solved by adding freezing and thawing steps to the conventional process. That is, in the freezing process, the moisture in the rice grains is bath-frozen to increase the volume of the rice grains by 1%, which damages the rice grain epidermis and breaks the nodule-like connections between the rice grain epidermis, and in the next thawing process. It is thawed and separated into pieces one by one.

Therefore, in the present invention, there is no risk of each grain of rice cracking, and the yield rate is not as bad as in the above-mentioned publication. Since the rice grains are frozen and thawed rather than frozen, there is no risk of deformation of the rice grains as in the conventional method, and each grain of rice can be provided with a beautiful shape.

Furthermore, it has the advantage that most conventional equipment can be used to carry out the manufacturing process.

In this way, in the present invention, the epidermis of the rice grain is hardened,
It is excellent as a liquid food because it improves blanching and heating, accelerates digestion time and range.

[Brief explanation of the drawing]

1 is a slope view of the rice grain before freezing, FIG. 1. Rice grain 2. Crack Patent applicant Kuwano Foods Co., Ltd. Figure 1 (A) Figure 1 (B) Figure 2 (A) Figure 2 (B)

Claims (1)

[Claims] For packaged cooked rice, rice containing an appropriate amount of moisture is sealed in a bag made of synthetic resin film, etc., and then heated with steam or other means to cook the rice inside the bag. After cooking, the rice is further frozen and thawed. A method for producing packaged cooked rice characterized by performing the following steps.