Plastic particles detection in animal flour using continuous terahertz waves

We have demonstrated the feasibility of terahertz (THz) frequency-domain spectroscopy to detect plastic contaminants in animal flour. The flour was held between two plastic membranes and different plastic contents were introduced into the sample while keeping the same weight. Free standing powder with and without contaminant samples were characterized using a compact continuous wave (CW) THz system. The variation of the transmission as a function of different plastic content in the samples were experimentally demonstrated. This work paves the way for the development of in-situ testing of food contaminants in animal flour using THz waves.