Today, I had the opportunity to go to Dandong Donggang to visit a pretty good rice processing enterprise. Donggang is located on the alluvial plain of the Yalu River. The land is fertile, the water network is abundant, and there is no major industrial pollution. It has always been an important producing area for high-quality rice. Although the output is not as good as the major rice producing areas such as Panjin and Heilongjiang, its variety and quality have a good reputation. The company I visited is the largest rice industry in this region. Its products were mainly used for export in the past, and now it has radiated to China 15 Large and medium cities. Its production line is very advanced and highly mechanized. During the visit, the factory director actively introduced to me that these complex and mechanized finishing processes lost a lot of nutrients, because the outer layer of rice grains (the same as wheat grains) and the germ are the most nutritious. Was grinded away. However, consumers are willing to buy such polished rice, which is beautiful and delicious. This is something that the entire rice industry cannot do. Next, let''s follow the milling rice production line to understand the finishing process:

　　 Step 1: The rice grains with rice hulls are initially screened in this machine to remove impurities Thing.

　　The second step: remove the rice hull (equivalent to the first grinding)

　　the third step: remove the bran hull (equivalent to the second grinding) to obtain brown rice (supermarket You can buy this kind of rice)

　　 Step 4: Screening to remove irregular grains and debris

　　 Step 5: High-speed impact milling (equivalent to milling Three times)

　　 Step 6: High-speed impact milling (equivalent to the fourth milling)

　　 Step 7: High-speed impact milling (equivalent to the milling Five times), the third to fifth milling is almost continuous, so far, the nutrient-rich outer layer (rice skin, bran skin, outer skin and part of the aleurone layer) and the most nutritious part of the germ are thoroughly Milled away to get polished rice. According to the introduction of the factory manager, assuming that the first step is 100 kg of rice, the milled rice obtained after five rounds of grinding before and after is less than 70 kg (ie, the out-of-city rate is less than 70%). The latter process also needs to remove broken rice, etc., and the final out-of-city rate is more than 60%.

　　 For more than 20 years, the total amount of staple foods (cereals) eaten by the Chinese people has continued to decrease according to the survey, and now urban residents have reduced to a reasonable recommended amount (250 to 400 grams per day, "Dietary Guidelines for Chinese Residents 2007" ")the following. On the other hand, rice noodles are getting more and more refined, and coarse grains are getting less and less. More than 93% of the ration rice is polished rice, and more than 83% of the flour is polished noodles. These changes are not conducive to reasonable nutrition, but also not conducive to the prevention and treatment of obesity, cardiovascular and cerebrovascular diseases, diabetes, cancer and other chronic diseases. The processing of rice and noodles is becoming more and more refined, which is a very worthy issue.