The "948" rice quality amylose tester has been successfully developed.

In order to fundamentally change the current rice quality, that is, the amylose content of rice, the Ministry of Agriculture listed the project of "rice quality amylose tester" in the "948" plan in 2001. The project, organized and implemented by China Agricultural University, aims to develop a high-quality rice quality tester suitable for all links and levels. Under the leadership of Professor Jia Guiru, director of the Department of Applied Physics of China Agricultural University, the project has been completed and achieved remarkable results.

It is reported that the rice quality amylose tester is composed of a computer, a 60-bit automatic sampler, an 8-channel peristaltic pump, an amylose module, an automatic gas-liquid separator and an optical fiber double-beam automatic photoelectric colorimeter. It uses 635nm semiconductor laser as monochromatic light source, computer communication and computer feedback control function software, detection accuracy and speed up to the international advanced level, a high degree of automation, suitable for quality inspection centers above the county level. In the economical "rice quality amylose tester". The instrument is composed of single-chip microcomputer, non-power automatic sampler, display and optical fiber double-beam automatic photoelectric colorimeter, which can display printing and data. The testing accuracy of the instrument reaches the international advanced level, and the testing speed is one sample every two minutes. The project has applied for two patents: "unpowered automatic sampler" and "18 microliter color pool". Among them, 18 micro-liter color pool has reached the international advanced level.

In the process of research and experiment, Professor Jia Guiru found that the higher the amylose content of the rice sample, the darker the color of the sample solution, and the lower the amylose content of the rice sample, the lighter the color of the sample solution. According to this phenomenon and the knowledge of colorimetry, a new detection method based on Israel science, namely "digital colorimetry detection method", is put forward. In theory, the detection accuracy of digital chromaticity detection method should not be lower than that of spectrophotometry, and the detection speed of digital chromaticity detection method can be more than 100 times faster than that of spectrophotometry.

Professor Hou Caiyun of the research group also used the digital colorimetric method to detect the content of amylose in rice. At the appraisal meeting of the "Tenth five-year Plan" project "Rapid testing system for High quality Rice quality" organized by the Ministry of Education in 2003, the rapid detection method of rice amylose content by digital colorimetry was the same as that of the current standard method. it is considered to have the leading level in the world.

Low-quality milk powder appeared in China in March 2004. the protein content of milk powder was quantitatively detected by digital colorimetry, which took 40 minutes. The process of testing whether the protein content of milk powder is qualified takes only 2 minutes. In June 2004, the rapid detection system of milk powder protein was identified by the Ministry of Education. The rapid detection system of milk powder protein developed by this project is suitable for the national conditions of our country and fills the domestic blank. The overall technology occupies a leading position in China. The application of digital image recognition technology in milk powder protein detection has reached the international advanced level.

The digital colorimetric detection method has the advantages of low cost, high precision and high speed, so it is possible to become a new detection method which is universally applicable in theory. The success of using digital colorimetric detection method in the detection of rice amylose, protein content and milk powder protein content gave great encouragement to the research group, and strengthened the confidence of the research group to further develop and improve digital colorimetric detection methods. The research group strives to perfect the digital colorimetric detection method into a universally applicable detection method in another 1-2 years, partially replacing spectrophotometry.