New type of combined rice mill: What are the key points of the process of the combined rice mill?

The process flow of a combined rice mill can be roughly divided into several sections: raw grain receiving section, cleaning section, husking section, coarse grain separation and grinding section, rice milling section, rice cooling section, polishing and color selection section, packaging section, etc. So, what are the key points of the process of the new type of combined rice mill?

New type of combined rice mill: What are the key points of the process of the combined rice mill?

1. Husking section

Husking refers to the process of rice husking. The main method is to achieve the purpose of husking by the relative movement of a pair of rubber rollers with different rotational speeds, squeezing and tearing the rice under a certain pressure. Then, by taking advantage of the difference in the suspension speeds of the rice and the rice husk, the rice mixture is separated from the rice husk through air suction. During the dehulling process, there are some cracked and incomplete grains in the rice, and due to the pressure between the rollers on the rice, some grains are crushed and broken.

2. Grain-brown separation and roughening section

The moisture content of brown rice before it enters the rice mill can also affect the rate of broken rice. When the moisture content is low, the pressure required for whitening increases, which inevitably leads to an increase in broken rice. Excessive moisture, loose texture and reduced strength of the rice will also increase the number of broken rice. In practice, broken rice can be reduced by tempering. The conditioning of brown rice mainly involves wetting and coarsening it, which can soften the bran, reduce the binding force between the bran and the endosperm, and also lower the temperature of the brown rice (usually the water temperature is lower than the room temperature), thereby reducing the pressure in the rice milling chamber and reducing the amount of broken rice produced during the milling process.

3. Rice milling section

Rice milling involves using sand rollers and iron rollers to grind out the grains and remove the outer layer of brown rice, thereby achieving the purpose of carbon whitening. Although brown rice is more nutritious than regular rice, the cellulose content in the bran of brown rice is much higher than that in the endosperm, and the taste of rice cooked directly is not good. Therefore, brown rice is generally not used to cook rice. Rice milling mainly utilizes the frictional force generated by the relative movement between the rice grains, between the rice grains and the white grinding roller, and between the rice grains and the rice sieve, as well as the cutting effect of the dense sand blades on the surface of the brown rice, to achieve the effect of wiping off and smoothing the surface of the brown rice.

4. Cooling rice section

After several rounds of rice milling, the temperature of the rice will be much higher than the room temperature. Entering the back polishing section without cooling will inevitably cause the rice to crack, increase the number of broken grains, and affect the quality of the finished product. Cooling the rice is to prevent it from cracking due to drastic changes in temperature and humidity and to reduce the number of broken grains. In addition, after the rice cools down, the temperature of the rice during polishing will not be too high, which is more suitable for the gelatinization of starch on the surface of the rice and the formation of a bright colloid film.

5. Polishing and color selection section

Polishing is to remove the bran powder adhering to the surface of white rice, making the surface of the white rice smooth and improving the appearance and color of the finished rice. Its working principle is to atomize water into tiny water droplets that adhere to the surface of white rice. The purpose of removing the bran powder and making the white rice smooth is achieved through the friction between the rice grains and between the rice grains and the polishing roller screen cylinder.

6. Production process control and other links

Maintaining flow balance during the production process is an important guarantee for stable production and reducing broken rice. Because a large amount of broken rice is produced when the processing stops. There are many reasons for the imbalance of flow during the production process, such as uneven raw materials, poor processing characteristics of raw materials, and lack of necessary buffer storage, etc.