Detection of lard adulteration in olive oil by using tapered Plastic Optical Fiber (POF) spectroscopy

摘要

Olive oil is one of the oil product that is most adulterated by cheap substance such as grease, tallow, and lard. In theother hand, tapered POF is widely used for many sensing applications, particularly for chemical and biosensor. In thispaper, the spectroscopy-based tapered POF for detecting lard adulteration in olive oil was investigated experimentally.The taper length and taper waist diameter were varied to evaluate the spectra characteristic of the tapered POF. Thesamples were made of olive oil adulterated by lard with the concentration of 0 – 5%. The result showed that the changesin taper geometry led the changes in some peaks. The new peaks were introduced at the wavelength of 650, 745, and 930nm. However, the change of the samples caused the wavelength shifting at the range of 920 – 930 nm. As the lardconcentration in olive oil increased, the intensity at the wavelength of 930 nm decreased. Hence, the wavelength of 930nm is potential to be utilized in intesity-based tapered POF for detecting lard adulteration.