DETECTING AFLATOXIN IN SINGLE CORN KERNELS BY TRANSMITTANCE AND REFLECTANCE SPECTROSCOPY

T. C. Pearson, D. T. Wicklow, E. B. Maghirang, F. Xie, F. E. Dowell
2001 Transactions of the ASAE  
Transmittance spectra (500 to 950 nm) and reflectance spectra (550 to 1700 nm) were analyzed to determine if they could be used to distinguish aflatoxin contamination in single whole com kernels. Spectra were obtained on whole com kernels exhibiting various levels ofbright greenish-yellow fluorescence. Afterwards, each kernel was analyzedfor aflatoxin following the USDA-FG1S Aflatest affinity chromatography procedures. Spectra were analyzed using discriminant analysis and partial least squares
more » ... egression. More than 95% of the kernels were correctly classified as containing either high (>100 ppb) or low «10 ppb) levels ofaflatoxin. Classification accuracy for kernels between 10 and 100 ppb was only about 25%, but these kernels do not usually affect total sample concentrations and are not as important. Results were similar when using either transmittance or reflectance, and when using either discriminant analysis or portia/least squares regression. The two-feature discriminant analysis oftransmittance data gave the best results. However, for automated high-speed detection and sorting, instrumentation that uses single-feature reflectance spectra may be more practically implemented. This technology should provide the com industry with a valuable tool for rapidly detecting aflatoxin in corn.
doi:10.13031/2013.6418 fatcat:bka3tzk3ufb2rauk2mujlst2ea