Food Safety Analysis System Based On The Full Spectrun Testing

This article firstly describes the significance of food safety and status of domestic and foreign testing,introducing the importance of food safety to social development and people's survival. With the extensive use of chemical pesticides, pesticide residues in vegetables leave much threat to people's healthy life,and what happened last SanLu melamine events and some times ago to just happen shuanghui lean meat essence events give our mental and physical health and state property, causing immeasurable losses which let us have a good reason for food testing dumped into more attention. Then introducing a number of food testing at home and abroad means and finding the means of present detection to reach people are far from the demand for it. Through the thorough research of domestic and international widely used detector, the article analyses their advantages and did amend or optimization in their shortcomings, to make the measurement range wider and the detector operation more convenient and concise.This design is based on the full spectrum theory to obtain monochromatic for food detection. Tungsten lamp can emit with continuous wavelength of light when the composite composite light through monochromator, due to the function of grating, the light of different wavelengths is spread out, and get a different wavelength of monochromatic. At present many detector using only monochromatic light source, measurement range is limited, but this thesis of the method makes the measurement range expanded,and meets more users' requirements.This paper take the detection of pesticide residues as an example, to describe the design and performance measurement of the detector. Carbamate and organophosphate pesticides inhibit cholinesterase, so that acetylcholine esterase can not be hydrolyzed, making it almost no color reaction, and the absorbance changes. Because the relation of Inhibition rate and the concentration of pesticides are proportional, by calculating the rate of inhibition we can determine whether there is a lot of pesticide residues.This design is based on the full spectrum theory to obtain monochromatic for food detection methods. This article is mainly divided into five modules:light module, photoelectric conversion module, signal amplifier module and single-chip microcomputer module and software design module. Each module of system are done in a more detailed introduction. Illuminant part chose tungsten lamp as input source; By comparison with other photoelectric devices, ultimately choosing photoelectric diode for photoelectric conversion; Choosing OP07,AD623 etc which are suitable for weak signal for signals integrated chip current/voltage conversion and amplification; Beacausing C8051F020 SCM itself have the strong functions, such as pieces AD converters, JTAG online and commissioning and 64 I/O port etc, the design choose it as the system controller; Finally choosing C51 as the system software design programming language, Including modules initialization, keyboard drive, LCD module design, AD transform module design and data calculations, etc.. This design features:small volume, light weight, detection range, easy to use.