Research on quick quality detection of box liquid milk with nondestructive testing method

According to the rheological theory in liquid milk quality degeneration process, imitating the free attenuation torsional vibration method in liquid viscosity measurement, an automatic detecting system is established to detect the quality of box liquid milk with Nondestructive testing method. The system which is composed of mass block (holding plate with box liquid milk), torsional spring and damper, can produce free evanescent pendulum vibration driven by the step motor Then computer processes and analyzes the torsional vibration signal measured by the accurate angle displacement transducer, calculates the frequency and damping coefficient of the signal and compares it with standard samples to judge the quality of product. The experimental result indicates that the method with the characteristics of low measure costs and high measure precision is the best substitute products of the traditional unpacking detecting method