Study The On-line Detection System Of The Fermented Food By The Biosensor

People's healthy were threatened because of the foodborne diseases caused by the microbiological contamination in food. In food processing, it has become a hot issue how to quickly, effectively and accurately detect harmful micro-organisms online, especially for the fermented food. Biosensors have been widely applied to detect the microbiology in food due to its advantages of the rapid assay, high accuracy, high safety and online assay. For Surface Plasmon Resonance biosensor (SPR), the detection is rapid, accurate, and there are high sensitivity and wide application. In order to get solutions for the problems of the microbial assay in the fermented food, the sauerkraut was selected as the experimental material in the research. And a online system about SPR biosensor was developed to detect the number of colonies. These results may be applied as the basis of the industrial online assay.This system consisted of three major components, which were the sampling devices, storage assay devices and waste pool. The storage assay device was the core of the whole system, which includes positioning mechanism, continuous testing mechanism, liquid storage sector and driving mechanism. According to this sequence of the test sample, buffer and antibodies, the SPR biosensor was moved, and the detection process was completed automatically. In the design process, a multi-way driving mechanism, including sliding screw drive, gear drive and ratchet mechanism, had been proposed. Then motion process was controlled by an AVR control system. With the help of man-machine interface, the motion process can be reset according to the actual requirements. Multiple samples can be detected with this system.By means of the virtual design and computer simulation, part entities established, the whole structure assembled, and the motion process analyzed were conducted to prove the usability of the storage assay device. The result suggested that the device meet the design reguirements.In accordance with the online testing conditions, the concentration of Escherichia coli was detected by the device at lab. Comparing the experiment results with the experiment results obtained by the convential methods (plate count), the average error value was 2.67%, and can be acceptable.In the research, virtual testing and experiment verification were used to prove the availability of the device together. Based on the SPR biosensor, an automatic assay device was developed. And its availability was successfully verified. Through the on-line inspection systems, fermented food can be quantitatively, automatically and multi-target detected. The device provides the basis for on-line detection of fermented food.