No-washing rice processing and technology
2018-04-22 16:00:22
The processing requirement of the rice-free rice is the use of high-quality rice. In addition to the necessary processes such as cleaning, cereals, grain separation, and whitening in the conventional rice production method, the processing technology also increases the selection and deep-grinding of brown rice. , White rice polishing, finished product grading and sealed small packaging and other several new processes. The production process can be simply expressed as: Mao Valley cleaning → shelling grain → coarse grain separation → brown rice selection → whitening and grinding → deep grinding → white rice polishing → finished product classification → sealed packaging. It can be seen that the difference between it and the conventional rice milling method is mainly reflected in the three procedures of brown rice selection, deep milling and white rice polishing.
Various studies have shown that it is more difficult to completely remove all kinds of impurities only by the rice cleaning process, because in the processing of rice, various new impurities such as rice husk, rice ash and alfalfa meal will also be produced. For this reason, the process of selecting and removing unpolished rice from the rice-scouring rice production process is added to ensure that the brown rice entering the rice-milling machine is pure, which is one of the keys to guarantee the quality of the unwashed rice. Apart from removing impurities, brown rice can also be used to classify brown rice in size, improve the uniformity of grain, and improve the quality of the final product.
The brown rice selection process first uses a planar rotary sieve to remove fine silt, lumps, ash, and most of the imperfect particles. If 20 mm x 20 mm long holes or Φ3.2 mm round holes are used, the removal rate of fine and coarse grains can reach 100%, the removal rate of imperfect particles can reach 80%, and the extraction rate of large grain brown rice can reach more than 55%. In addition, the shoulder stones and light impurities mixed in the brown rice were removed using a density stone remover and winnowing method. According to the actual situation of the rice mills in China, the smuts and rice husks that have not been removed during the rice cleanup, such as rice husks and stalks that have not been removed, can be concentrated in valleys separated by coarse grain and then carried out in the valleys. Supplementing winnowing and density sorting, it has a great impact on guaranteeing the quality of products that are not washed.
China's usual whitening technology mostly uses one machine to two machines, which will affect the surface finish and grain hardness of the product due to strong peeling, and it is easy to have a high rate of broken rice. To avoid the rice out of rice, at least it must be divided into three whites, that is, three meters out of rice. The first grinded material accounted for 4.5%-5.0% of the weight of brown rice, and the second grinded material accounted for 4.5%. The two paths grind about 9% of the weight of brown rice, which is equivalent to the entire cortex of brown rice. The third grinded material accounted for 2% -3%, basically belongs to the sub-aleurone layer, containing protein 18%, fat 10% -13%, vitamin B1 2.7 mg / 100 g, is a high protein nutritional rice flour, fully edible . In this way, the multi-machine grinding of white rice not only improves the grinding quality of the finished product, but also provides conditions for the full utilization of the milled material.
Multi-machine whitening requires a reasonable selection of the speed of each rice mill, and a reasonable ratio of the sand roller and the iron roller rice machine, such as a sand roller rice machine equipped with 1,400-14,050 rev/min in three lanes. Iron roller rice machine with 900-950/min. In view of the specific conditions of the existing rice mills in China, an additional blower rice machine can be added on the basis of the original two mills. In addition to maintaining the original rice production, some of the second machine rice are separated into three machines for grinding. You can mass-produce no-scoop rice.
The polishing of white rice is the key to the production of no-scouring rice. It is sprayed on the surface of rice grains with an aqueous solution of polishing agent to form a very thin gel film, so that pearl luster is produced and the appearance of rice grains is crystal clear and jade. In this respect, there is a type of polishing apparatus that consists of two polishing chambers, upper and lower, with iron rollers and non-toxic nylon polishing. After the white rice enters the polishing chamber, the surface of the rice is gelatinized by the heat produced by the polishing agent aqueous solution and the polishing roller, which are composed of glucose and magnesium silicate, and a very thin gel layer is formed, thereby resulting in obvious Pearl wax light. Some Italian manufacturers can also get pearlized oiled rice by spraying Vaseline oil on the surface of rice.
A clean rice method reported in Japan is to surface-treat polished rice with 55%-60 degrees Celsius for 10-15 minutes to dissolve the dust or grease adsorbed on the surface of rice grains. Here, the two factors of temperature and time should be strictly controlled. If the temperature is lower than 55 degrees Celsius and the time is less than 10 seconds, the treatment effect is not obvious. However, when the temperature exceeds 60 degrees Celsius and the time is longer than 15 seconds, ethanol will be immersed inside the rice grain. , At the same time, it is easy to cause the danger of operation.
The amount of ethanol was approximately equal to that of rice. The rice was dried immediately after treatment to remove residual ethanol. Drying can be performed by hot air drying, cold air drying, natural drying or reduced pressure drying. If the rice is treated with hot air at 80 degrees Celsius for 5 minutes and then treated with cold air at 20 degrees Celsius for 10 minutes, the purpose can be achieved.
Various studies have shown that it is more difficult to completely remove all kinds of impurities only by the rice cleaning process, because in the processing of rice, various new impurities such as rice husk, rice ash and alfalfa meal will also be produced. For this reason, the process of selecting and removing unpolished rice from the rice-scouring rice production process is added to ensure that the brown rice entering the rice-milling machine is pure, which is one of the keys to guarantee the quality of the unwashed rice. Apart from removing impurities, brown rice can also be used to classify brown rice in size, improve the uniformity of grain, and improve the quality of the final product.
The brown rice selection process first uses a planar rotary sieve to remove fine silt, lumps, ash, and most of the imperfect particles. If 20 mm x 20 mm long holes or Φ3.2 mm round holes are used, the removal rate of fine and coarse grains can reach 100%, the removal rate of imperfect particles can reach 80%, and the extraction rate of large grain brown rice can reach more than 55%. In addition, the shoulder stones and light impurities mixed in the brown rice were removed using a density stone remover and winnowing method. According to the actual situation of the rice mills in China, the smuts and rice husks that have not been removed during the rice cleanup, such as rice husks and stalks that have not been removed, can be concentrated in valleys separated by coarse grain and then carried out in the valleys. Supplementing winnowing and density sorting, it has a great impact on guaranteeing the quality of products that are not washed.
China's usual whitening technology mostly uses one machine to two machines, which will affect the surface finish and grain hardness of the product due to strong peeling, and it is easy to have a high rate of broken rice. To avoid the rice out of rice, at least it must be divided into three whites, that is, three meters out of rice. The first grinded material accounted for 4.5%-5.0% of the weight of brown rice, and the second grinded material accounted for 4.5%. The two paths grind about 9% of the weight of brown rice, which is equivalent to the entire cortex of brown rice. The third grinded material accounted for 2% -3%, basically belongs to the sub-aleurone layer, containing protein 18%, fat 10% -13%, vitamin B1 2.7 mg / 100 g, is a high protein nutritional rice flour, fully edible . In this way, the multi-machine grinding of white rice not only improves the grinding quality of the finished product, but also provides conditions for the full utilization of the milled material.
Multi-machine whitening requires a reasonable selection of the speed of each rice mill, and a reasonable ratio of the sand roller and the iron roller rice machine, such as a sand roller rice machine equipped with 1,400-14,050 rev/min in three lanes. Iron roller rice machine with 900-950/min. In view of the specific conditions of the existing rice mills in China, an additional blower rice machine can be added on the basis of the original two mills. In addition to maintaining the original rice production, some of the second machine rice are separated into three machines for grinding. You can mass-produce no-scoop rice.
The polishing of white rice is the key to the production of no-scouring rice. It is sprayed on the surface of rice grains with an aqueous solution of polishing agent to form a very thin gel film, so that pearl luster is produced and the appearance of rice grains is crystal clear and jade. In this respect, there is a type of polishing apparatus that consists of two polishing chambers, upper and lower, with iron rollers and non-toxic nylon polishing. After the white rice enters the polishing chamber, the surface of the rice is gelatinized by the heat produced by the polishing agent aqueous solution and the polishing roller, which are composed of glucose and magnesium silicate, and a very thin gel layer is formed, thereby resulting in obvious Pearl wax light. Some Italian manufacturers can also get pearlized oiled rice by spraying Vaseline oil on the surface of rice.
A clean rice method reported in Japan is to surface-treat polished rice with 55%-60 degrees Celsius for 10-15 minutes to dissolve the dust or grease adsorbed on the surface of rice grains. Here, the two factors of temperature and time should be strictly controlled. If the temperature is lower than 55 degrees Celsius and the time is less than 10 seconds, the treatment effect is not obvious. However, when the temperature exceeds 60 degrees Celsius and the time is longer than 15 seconds, ethanol will be immersed inside the rice grain. , At the same time, it is easy to cause the danger of operation.
The amount of ethanol was approximately equal to that of rice. The rice was dried immediately after treatment to remove residual ethanol. Drying can be performed by hot air drying, cold air drying, natural drying or reduced pressure drying. If the rice is treated with hot air at 80 degrees Celsius for 5 minutes and then treated with cold air at 20 degrees Celsius for 10 minutes, the purpose can be achieved.