JPH01213301A - Production of purified rice starch - Google Patents

Abstract

PURPOSE:To efficiently produce the subject high purified rice starch useful for papermaking, cosmetics, etc., at a low cost, by carrying out grain polishing of rice grains, then removing the outside tissue, arranging the grains in a speci fied size, subsequently passing the grains through a crusher and passing the obtained crushed granules to a liquid cyclone, etc. CONSTITUTION:Rice grains are subjected to grain polishing using a rice milling machine, and the outside tissue of the rice grains 7, i.e., pericarps 1 and seeds 2 are removed. The obtained grains are then subjected to a grinding type crusher such as a stamp mill, or a grinding mill, and passed through a sieve to arrange the resultant granules to a size of <=30mum. Furthermore, the obtained granules are subjected to a high-pressure hydraulic machine such as a homogenizer while suspended normally in 10-50 times amount of water and the resultant crushed granules are passed through a liquid cyclone or a slit type sieve with about 5mum slits to remove finely powdered impurities.

Description

[Detailed Description of the Invention] [Field of Industrial Use] Due to the high content of rice starch, the application of rice starch for industrial use has not progressed in Japan. If rice starch becomes the same price as rice starch or pond starch, rice starch will be used as a sizing agent for paper manufacturing because of its finer particles and angular polygonal shape compared to pond starch. As a coach ink agent, it can fill in the unevenness of the paper surface to create a smooth surface, and the characteristics of starch that fall off or peel off from the paper surface are less, resulting in clearer printing.

Also, when used in cosmetics, it has the same effect,
The makeup has a good finish and shows characteristics such as less crumbling.

The present invention provides a method for producing inexpensive and highly purified rice starch for use in paper manufacturing, cosmetics, or similar purposes.

[Conventional technology]

When using rice starch for industrial purposes, it is necessary to remove the proteins contained in rice starch. The ``alkaline purification method'' was commonly used to remove proteins from rice starch. This method uses a dilute solution of caustic soda to dissolve and remove proteins contained in rice particles, but this method has the following drawbacks. That is, alkali treatment takes time. Alkali remains in rice starch. Damage to rice starch occurs due to alkali. The yield of rice starch is not good. It is difficult to utilize waste.

Furthermore, in addition to the "alkaline purification method," the "surfactant method" and [
Ultrasonic methods have been studied, but they all have drawbacks.
It has not been put into practical use.

[Problems to be Solved by the Invention] Therefore, the inventors of the present invention have developed a method to eliminate the drawbacks that could not be solved by conventional methods, such as long-time purification processing, residual alkali, destruction of rice starch, low yield, and waste problems. , we studied a method for producing rice starch that allows for continuous processing, short refining processing time, no deterioration of rice starch, no contamination of impurities, and can be mass-produced.
The invention has been completed.

[Means to solve the problem]

The present inventor has elucidated the structure of rice particles, and by using various types of crushers in combination, we have succeeded in peeling off and removing impurities surrounding rice starch other than rice starch particles, or by using a liquid cyclone. Alternatively, remove this with a slit sieve and classify purified rice starch with a size of around 5 microns.
I was able to select.

More specifically, as shown in Figure 1, the structure of a rice grain is arranged in the order of pericarp, seed coat, and embryo from the outside, and rice starch is composed of about 10 cells in the starch storage cells of the endosperm tissue. exist. As shown in Figure 2, the cell membrane is mainly composed of cellulose and hemicellulose, and proteins and fats are attached to the surface of each starch particle. Cell membranes are easily broken by ordinary crushers, so the cell membranes can be separated using gravity classification or sieving methods.
It can be removed. Since the protein is attached to the surface of the rice starch particles, it cannot be separated by the usual FiM pulverization method. For this purpose, the "alkali purification method," the "surfactant method," and the "ultrasonic purification method" were tried, but no satisfactory results were obtained.

In recent years, high-pressure equipment has been developed that creates fine particles by applying high pressure to water and ejecting it through a narrow mouth, making it possible to pulverize solids underwater. One of these machines is a homogenizer. After pulverizing rice particles to about 30 microns using a regular grinder, they are suspended in 10 to 50 times the volume of water and passed through a homogenizer to produce 500 to 1,000 kg of rice particles.
When the rice starch particles are ejected under a strong pressure of -'aA, the membrane containing proteins and fat attached to the surface of the rice starch particles is peeled off by the impact of the water, and then the rice starch particles are pulverized. Rice starch particles are relatively hard and unbreakable, with a size of 5 to 10 microns. After that, by passing through a hydrocyclone or a 3-5 micron slit sieve, impurities are removed and the refined rice starch can be easily separated.7 [Effects of the Invention] In this way, the rice particles After polishing, it is crushed to a size of about 30 microns using a regular crusher, suspended in 10 to 50 times the volume of water, and then applied to a high-pressure device such as a homogenizer.
Pulverize in water and remove impurities using a liquid cyclone or
By separating and refining rice starch using a micron slit sieve, highly purified rice starch can now be produced inexpensively, efficiently, and on an industrial scale.

Furthermore, since no chemicals are used for the by-products recovered at the same time, such as proteins, cellulose, hemicellulose, etc., they can be effectively utilized by drying them after collection. In addition, it is easy to handle wastewater.

[Brief explanation of the drawing]

Figure 1 shows the structure of unrefined rice grains (brown rice). Tissues are arranged in the order of pericarp, seed coat, and endosperm from the surface of the brown rice grain, indicating that starch storage cells exist within the endosperm tissue. Figure 2 shows the structure of starch storage cells. The outside of the starch storage cell is covered with a cell membrane rich in cellulose and hemicellulose, and rice starch particles exist within the cell membrane. Rice starch particles are covered with a protein-rich membrane. 1...Pericarp, 2...Seed coat, 3...Endosperm, 4...
・Starch storage cell, 5... Cell membrane, 6.
......Protein film, 7...Rice starch particles.

Claims (1)

[Claims] After polishing the rice grains using a whitening machine to remove the outer structure of the rice grains, that is, the pericarp and seed coat, the rice grains are milled using a grinding mill such as a stamp mill or a grind mill and a sieve to reduce the size to 30 microns or less. Purification obtained by adjusting the particle size to Method for producing rice starch.