Determining sugar content in sugarcane plants using LED spectrophotometer

摘要

Sugar production from sugarcane plants depends on their sugar content in the unit of % Brix. The higher value of Brix percentage, the sugar production will be increase. In the field of sugarcane, there is term of Commercial Cane Sugar (CSS) or Sugarcane quality index which describes the approximation percentage of sugar content from fresh sugar cane. The idea of non-destructive measurement leads us to propose the designed nondestructive Brixmeter based on the optical properties of sugar content. This design of measurement in the scale of Brix uses photometer with spectroscopic techniques. Our instrument employs LED as a light source and photodiode array as a detector. The system employed a pin photodetector as a sensor, LED, operational amplifiers (Op-Amp), an ADC, and a computer. The main operation of the measurement system was conducted by the sensor and the computer controlled system. The signal from pin photodiode sensor was sent to the signal processing unit (op-amp and ADC). Then the digital code was counted by controller and displayed in the computer screen. The LED-refractometer was calibrated using a standard solution liquid, and the results compared to the digital spectrophotometer (scientific spectrophotometer). The results showed that the LED-refractometer is able to measure sugar content of sugarcane plantation in field in the accuracy of 95% compare to the digital spectrophotometer as a standard meter to measured sugar content of solution.