Rapid screening and visual tracing of melamine in soybean meal by NIR microscopy imaging

Abstract

Near infrared microscopy imaging offers the opportunity to explore not only what kinds of chemical species are present at micro-scale level but also where the chemical species would be present. By revealing the spectral and spatial information, the technique can identify and localize any interested component. This study investigates the feasibility of using Near infrared microscopy imaging to detect melamine in soybean meal. The results showed that 6805 cm-1 is very sensitive for melamine but not for soybean meal, so can be used for univariate analysis. Single wavelength image and peak integration image at 6805 cm-1 are simple and effective methods to detect the melamine in soybean meal. Furthermore, Principal Component Analysis is applied to detect the melamine in soybean meal.