JPS60224456A - Preparation of cooked and dried rice - Google Patents

Abstract

PURPOSE:To prepare cooked and dried rice which can be converted to a high- quality cooked rice only by pouring hot water thereto or by boiling for a short time, by steaming polished rice to convert the starch to alpha-form, adjusting the water-content of the rice, and dilating the rice with super-heated steam. CONSTITUTION:Polished rice is washed, immersed in water, drained, and steamed with steam of normal pressure for about 30-50min to obtain steamed rice having an alpha-starch content of 50-60% and composed of rice grains separable from each other. The steamed rice is dried to a water-content of 5-20% with hot air, and is heated in wet state with super-heated steam of 120-130 deg.C for 5-30sec to effect the conversion of the most part of the beta-starch to alpha-starch simultaneous to the dilation of the rice grain.

Description

[Detailed Description of the Invention] The present invention relates to a method for producing instant cooked rice, and in particular, the method involves steaming washed polished rice to gelatinize the starch, further adjusting the water content, and then expanding the rice with superheated steam. Alternatively, it is characterized in that high-quality cooked rice can be prepared by simply boiling it for a short time.

Dry rice is made by heating rice to gelatinize the starch and then drying it.
Conventionally, rice is steamed or cooked and then dried by hot air drying, freeze drying, rapid dehydration using heated oil, indirect heating contact method using salt or borax, heating vacuum swelling method, etc. was attempted. However, dried cooked rice produced by these conventional methods has problems in its production method and quality, and is particularly unsatisfactory in terms of adhesion of rice grains to each other during drying and taste and texture after reconstitution.

For example, when polished rice is cooked, the surface of the rice grains becomes gelatinized and they stick to each other to form lumps, which takes a long time to dry and causes uneven drying. Moreover, it is difficult to separate the dry lumps of rice one by one. It requires a lot of effort. In order to solve this problem, attempts have been made in the past to immerse polished rice in hot water and then steam it, or to pressure steam it. However, even with these methods, the phenomenon of clumping of dried rice cannot be avoided. Previously, attempts have also been made to add edible oils and surfactants to polished rice in advance. However, although this method prevents the clumping of dried rice, it causes a significant deterioration in taste and texture after restoration.

The reason why conventional methods cause such problems is that they first try to completely gelatinize the starch.

In other words, when rice is steamed and cooked until the starch is completely gelatinized, adhesion forces inevitably occur on the surface of the rice grains.

The present inventor has discovered that if polished rice is steamed under conditions where about 50 to 60% of the starch becomes pregelatinized, the steamed rice will hardly have any sticking force.
In addition to discovering that it can be dried in a particle state,
It was discovered that when this dried rice is heated with superheated steam, almost all of the remaining β-starch is gelatinized, resulting in a product with good taste and texture.In addition, the rice grains swell and become a rice grain with excellent reboiling properties. The present invention is based on these findings.

The present invention will be explained in detail below.

The present invention comprises a process of steaming polished rice, a process of drying the steamed rice with hot air, and a process of wet heating the dried rice.

First, polished rice is washed, soaked in water, drained, and then steamed with normal pressure steam to produce steamed rice. The reason why polished rice is soaked in water is to adjust the water content in the rice grains, and depending on the type of rice, the water content reaches about 40% by soaking for about 1 to 3 hours. There are no particular limitations on the method of steaming this rice. For example, put drained rice in a steamer basket,
It is steamed by blowing steam under normal pressure.

By steaming rice for 30 to 50 minutes, the degree of gelatinization is 50 to 60.
There is almost no horizontal adhesion force on the surface of the steamed rice.

Next, this steamed rice is dried with hot air.

Since the rice grains of steamed rice are independent of each other and are granular, it is appropriate to use a ventilated dryer such as a fluidized bed dryer. 8
The steamed rice is dried by passing through the rice at a moderate speed, and the moisture content is adjusted to 5 to 20%.

Finally, the dried rice is heated to 120~300℃ with superheated steam.
Wet heat for 30 seconds. By heating, most of the β-starch becomes pregelatinized, and at the same time, the rice grains swell and become more easily rehydrated.

Examples of the present invention are shown below.

Example Wash 1 kg of polished rice and soak in water for 1 hour.

The soaked rice was drained and steamed in a steamer for 50 minutes.

This steamed rice was dried in a fluidized bed with hot air at a temperature of 0.degree. C. and a wind speed of 3 m/sec, and the water content was adjusted to ls%. Next, this dried rice is heated with superheated steam at a temperature of 130°C and a wind speed of 11 m/sec for 30 seconds to obtain puffed rice with a gelatinization degree of 90% or more.
I got it. When 270 mt of boiling water was added to 180 g of this puffed rice and left to stand for 5 minutes, cooked rice having the same taste and texture as cooked rice was obtained.

Claims (1)

[Claims] Polished rice is soaked in water to absorb water, then drained, steamed with normal pressure steam for 20 to 60 minutes to make steamed rice, and then the steamed rice is dried with hot air to a moisture content of 5 to 20 cm. The method for producing dried cooked rice is then wet-heated using superheated steam at 120 to 300°C for 5 to 30 seconds to gelatinize the starch and expand the rice grains.