Application of microwave spectroscopy analysis on determining quality of vegetable oil

Abstract

Recently there has been an increasing interest in the classification of edible oils as an effective means to examine authenticity and to detect possible adulteration of virgin olive oils with seed oils or low-quality olive oils. Classical methods based on gas chromatography (GC) and high-performance liquid chromatography (HPLC) are too expensive for widespread industrial use and require samples to be analysed in dedicated laboratories thus incurring a significant time penalty. This paper demonstrates that microwave spectrometry is able to offer realtime measurement of oils adequate for determining product authenticity. It does this by evaluating a bespoke sensor system which is used to measure the dielectric properties common-place edible oils. In particular, the capability of the system to distinguish between these oils, even when mixed, is demonstrated. This is important as it is a common technique used by fraudsters in the production of counterfeit oils.