Study of milk concentration detection based on the AC signal-modulated LED

As milk consumption increases, rapid detection of milk concentration is becoming more and more crucial. In this research, we propose an LED-based milk concentration detection system, which is a new detection method that detects milk concentration by loading the LED with RF signals. The system includes an arbitrary waveform generator (AWG), LED, lampshade, silicon photo dioxide (PD), oscilloscope, and other components. After passing through different concentrations of milk solution, the light signal carrying a specific frequency is received by the PD, and after photoelectric conversion, the signal carrying a specific frequency in the light signal is converted out, and the concentration of the milk solution to be measured is obtained by reading the peak value measured by the oscilloscope. The experiments validated different brands of milk solutions with varying concentrations, demonstrating the feasibility of LED-based milk concentration detection, and the test analysis was performed for the same brand of milk solutions with varying concentrations, yielding a quadratic fit R2=0.9169, confirming that the system has good sensing performance for milk concentration and validating the method's feasibility.