Comparison of Multiple Moisture-Measurement Techniques Applied on Biological Tissue

This papers presents a measurement setup which combines three different methods indicating the moisture fraction of a sample. This is managed by measuring the weight, the absolute electrical impedance with a harmonic excitation between 10 Hz to 1000 Hz and the surface reflectance of the sample with a spectroscope between 160nm to 1100nm. The measurements are carried out over 50 h every 5 min using a piece of porcine meat. The results show clear evidences that the dehydration occurs on the surface until the water inside is diffused to the surface completely. This can be seen on significant wavelengths of absorption bands in the reflected spectrum like 540nm, 575nm and 970nm (oxyhaemobglobin and water) and in the impedance measurement that are both set into ratio with the weight loss of the sample.